An invention is a new process, method, or device, including improvements made to existing ones.
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In modern clothing and fashion design, a button is a small fastener, most commonly made of plastic, but also frequently of seashell, which secures two pieces of fabric together. In archaeology, a button can be a significant artifact. In the applied arts and in craft, a button can be an example of folk art, studio craft, or even a miniature work of art.
Buttons are most often attached to articles of clothing but can also be used on containers such as wallets and bags. However, buttons may be sewn onto garments and similar items exclusively for purposes of ornamentation. Buttons serving as fasteners work by slipping through a fabric or thread loop, or by sliding through a buttonhole.
Some museums and art galleries hold culturally, historically, politically, and/or artistically significant buttons in their collections. The Victoria & Albert Museum has many buttons, particularly in its jewellery collection, as does the Smithsonian Institution.
Hammond Turner & Sons, a button-making company in Birmingham, hosts an online museum with an image gallery and historical button-related articles, including an 1852 article on button-making by Charles Dickens. In the USA, large button collections
A rechargeable alkaline battery (also known as alkaline rechargeable or rechargeable alkaline manganese (RAM)) is a type of alkaline battery that is rechargeable. The first-generation rechargeable alkaline technology was developed by Battery Technologies Inc in Canada and licensed to Pure Energy, EnviroCell, Rayovac, and Grandcell. Subsequent patent and advancements in technology have been introduced. The shapes include AAA, AA, C, D, and snap-on 9-volt batteries. Rechargeable alkaline batteries are manufactured fully charged and have the ability to carry their charge for years, longer than most NiCd and NiMH batteries, which self-discharge. Rechargeable alkaline batteries can have a high recharging efficiency and have less environmental impact than disposable cells.
Although these batteries can be used in any device that supports a standard size (AA, AAA, C, D, etc.), they are formulated to last longest in periodical use items. This type of battery is best suited for use in low-drain devices such as remote controls or for devices that are used periodically such as flashlights, television remotes, portable radios, etc. If they are discharged by less than 25%, they can be recharged
A sewing machine is a machine used to stitch fabric and other materials together with thread. Sewing machines were invented during the first Industrial Revolution to decrease the amount of manual sewing work performed in clothing companies. Since the invention of the first working sewing machine, generally considered to have been the work of Englishman Thomas Saint in 1790, the sewing machine has vastly improved the efficiency and productivity of fabric, clothing and needle industries.
Home sewing machines are designed for one person to sew individual items while using a single stitch type. Modern sewing machines are designed in such a way that the fabric easily glides in and out of the machine without the hassle of needles and thimbles and other such tools used in hand sewing, automating the process of stitching and saving time.
Industrial sewing machines, by contrast, are larger, faster, more complex, and more varied in their size, cost, appearance, and task.
The fabric shifting mechanism may be a workguide or may be pattern-controlled (e.g., jacquard type). Some machines can create embroidery-type stitches. Some have a work holder frame. Some have a workfeeder that can move
The atmometer or evaporimeter is a scientific instrument used for measuring the rate of evaporation from a wet surface to the atmosphere. It was invented by either the Dutch scientist Pieter van Musschenbroek (1692–1761) or the Scottish mathematician and engineer Sir John Leslie (1766–1832).
A simple set up may be made by use of a porous flat plate-like object (a filter paper, for example) which can draw water from an easily measurable source (a graduated cylinder, for example) via a wick of some sort. As water evaporates from the surface, it tends to draw more water from the source through the wick by capillary action to replace the water lost by evaporation. By periodic measurements of the quantity of water remaining in the graduated cylinder, a rate of evaporation can be established. Also, using the surface area of the plate, we can establish a rate of evaporation per unit area.
A Kelvin bridge (also called a Kelvin double bridge and in some countries a Thomson bridge) is a measuring instrument invented by William Thomson, 1st Baron Kelvin. It is used to measure an unknown electrical resistance below 1 Ω. Its operation is similar to the Wheatstone bridge except for the presence of additional resistors. These additional low value resistors and the internal configuration of the bridge are arranged to substantially reduce measurement errors introduced by voltage drops in the high current (low resistance) arm of the bridge. It consist of two ratio arms. The outer ratio arm contains the known resistors and the inner ratio arm helps to connect the one terminal of the galvanometer at the appropriate point (which was the disadvantage of the Kelvin first bridge).
There are some commercial devices reaching accuracies of 2% for resistance ranges from 0.000001 to 25 Ω. Often, ohmmeters include Kelvin bridges, amongst other measuring instruments, in order to obtain large measure ranges, for example, the Valhalla 4100 ATC Low-Range Ohmmeter.
The instruments for measuring sub-ohm values are often referred to as low-resistance ohmmeters, milli-ohmmeters, micro-ohmmeters,
A mousetrap is a specialized type of animal trap designed primarily to catch mice; however, it may also trap other small animals. Mousetraps are usually set in an indoor location where there is a suspected infestation of rodents. There are various types of mousetrap, each with its own advantages and disadvantages. Larger traps are designed to catch other species of animals; such as rats, squirrels, other small rodents, or other animals.
The first spring-loaded mouse trap was invented by William C. Hooker of Abingdon Illinois, who received US patent 528671 for his design in 1894. James Henry Atkinson, a British inventor who in 1897 invented a prototype called the "Little Nipper", probably had seen the Hooker trap in the shops or in advertisements and used it as the basis of his model.
It is a simple device with a heavily spring-loaded bar and a trip to release it. Cheese may be placed on the trip as bait, but other food such as oats, chocolate, bread, meat, butter and peanut butter are commonly used. The spring-loaded bar swings down rapidly and with great force when anything, usually a mouse, touches the trip. The design is such that the mouse's neck or spinal cord will be broken,
A record changer or autochanger is a device that plays multiple phonograph records in sequence without user intervention. Record changers first appeared in the late 1920s, and were common until the 1980s.
The record changer with a stepped center spindle design was invented by Eric Waterworth of Hobart, Australia, in 1925. He and his father took it to Sydney, and arranged with a company called Home Recreations to have it fitted in their forthcoming phonograph, the Salonola. Although the Salonola was demonstrated at the 1927 Sydney Royal Easter Show, Home Recreations went into liquidation and the Salonola was never marketed. In 1928 the Waterworths traveled to London, where they sold their patent to the new Symphony Gramophone and Radio Co. Ltd. Eric Waterworth built three prototypes of his invention and one of these was sold to Home Recreations as a pattern for their proposed Salonola record player. This prototype is now reported to be in the collection of the Powerhouse Museum in Sydney. The second prototype went to England with Eric and his father and was sold as part of the deal with the Symphony Gramophone and Radio Company. The fate of this machine is unknown. The third
The Kelvin water dropper, invented by Lord Kelvin (1867), is a type of electrostatic generator. Kelvin referred to the device as his water-dropping condenser. The apparatus is sometimes called the Kelvin hydroelectric generator, the Kelvin electrostatic generator, or Lord Kelvin's thunderstorm. The device uses falling water drops to generate voltage differences by using positive feedback and the electrostatic induction occurring between interconnected, oppositely charged systems.
The simplest setup for this is as pictured at right. A reservoir has two holes that drip water (or other liquid). The streams of dripping water each pass through a conducting ring, and land in a bucket. The buckets must be electrically isolated from each other and from their environment. Similarly, the rings must be electrically isolated from each other and their environment. The left ring is electrically connected with (wired to) the right bucket and the right ring is wired to the left bucket. It is essential that each ring be placed around the point at which the stream of water passing through it first breaks into drops.
If the buckets are metal (conducting) the wires may be attached to the buckets.
A seat belt, sometimes called a safety belt, is a safety harness designed to secure the occupant of a vehicle against harmful movement that may result during a collision or a sudden stop. A seat belt reduces the likelihood and severity of injury in a traffic collision by stopping the vehicle occupant from hitting hard against interior elements of the vehicle or other passengers (the so-called second impact), by keeping occupants positioned correctly for maximum benefit from the airbag, if the vehicle is so equipped, and by preventing occupants being ejected from the vehicle.
Seat belts were invented by George Cayley in the early 19th century, though Edward J. Claghorn of New York, was granted the first patent (U.S. Patent 312,085, on February 10, 1885 for a safety belt). Claghorn was granted United States Patent #312,085 for a Safety-Belt for tourists, painters, firemen, etc. who are being raised or lowered, described in the patent as "designed to be applied to the person, and provided with hooks and other attachments for securing the person to a fixed object."
In 1911, Benjamin Foulois had the cavalry saddle shop fashion a belt for the seat of Wright Flyer Signal Corps 1. He
The Newtonian telescope is a type of reflecting telescope invented by the British scientist Sir Isaac Newton (1642–1727), using a concave primary mirror and a flat diagonal secondary mirror. Newton’s first reflecting telescope was completed in 1668 and is the earliest known functional reflecting telescope. The Newtonian telescope's simple design makes them very popular with amateur telescope makers.
Newton’s idea for a reflecting telescope was not a new one. Galileo Galilei and Giovanni Francesco Sagredo had discussed using a mirror as the image forming objective soon after the invention of the refracting telescope, and others, such as Niccolò Zucchi, claimed to have experimented with the idea as far back as 1616. Newton may even have read James Gregory's 1663 book Optica Promota which described reflecting telescope designs using parabolic mirrors (a telescope Gregory had been trying unsuccessfully to build).
Newton built his reflecting telescope because he suspected that it could prove his theory that white light is composed of a spectrum of colors. Color distortion (chromatic aberration) was the primary fault of refracting telescopes of Newton's day, and there were many theories
The parallel motion is a mechanical linkage invented by the Scottish engineer James Watt in 1784 for his double-acting steam engine.
In previous engines built by Newcomen and Watt, the piston pulled one end of the walking beam downwards during the power stroke using a chain, and the weight of the pump pulled the other end of the beam downwards during the recovery stroke using a second chain, the alternating forces producing the rocking motion of the beam. In Watt's new double-acting engine, the piston produced power on both the upward and downward strokes, so a chain could not be used to transmit the force to the beam. Watt designed the parallel motion to transmit force in both directions whilst keeping the piston rod vertical. He called it "parallel motion" because both the piston and the pump rod were required to move vertically, parallel to one another.
In a letter to his son in 1808, James Watt wrote "I am more proud of the parallel motion than of any other invention I have ever made."
See the diagram on the right. A is the journal (bearing) of the walking beam KAC, which rocks up and down about A. H is the piston, which is required to move vertically but not horizontally. The
Horstmann suspension is a type of tracked suspension devised by the British engineer Sidney Horstmann in 1922.
The system uses coil springs and has the advantages of a relatively long travel and, consisting of a self-contained bogie that is bolted to the hull, causing little or no encroachment on internal hull space. In addition, the entire suspension unit may be relatively easily removed and replaced if damaged, e.g., by mines.
The name "Horstmann suspension" also refers to suspension built by the Horstman company (now Horstman Defence Systems Ltd) whether of the bogie type, torsion beam design, hydrogas, hydropneumatic or other.
The Horstmann system was used on, amongst others, the following vehicles:
Horstman built suspension is used on
Salamanca was the first commercially successful steam locomotive, built in 1812 by Matthew Murray of Holbeck, for the edge railed Middleton Railway between Middleton and Leeds. It was the first to have two cylinders. It was named after the Duke of Wellington's victory at the battle of Salamanca which was fought that same year.
Salamanca was also the first rack and pinion locomotive, using John Blenkinsop's patented design for rack propulsion. A single rack ran outside the narrow gauge tracks and was engaged by a large cog wheel on the left side of the locomotive. The cog wheel was driven by twin cylinders embedded into the top of the centre-flue boiler. The class was described as having two 8"x20" cylinders, driving the wheels through cranks. The piston crossheads worked in guides, rather than being controlled by parallel motion like the majority of early locomotives. The engines saw up to twenty years of service.
Four such locomotives were built for the railway. Salamanca was destroyed six years later, when its boiler exploded. According to George Stephenson, giving evidence to a committee of Parliament, the driver had tampered with the boiler safety valve.
The abacus (plural abaci or abacuses), also called a counting frame, is a calculating tool used primarily in parts of Asia for performing arithmetic processes. Today, abaci are often constructed as a bamboo frame with beads sliding on wires, but originally they were beans or stones moved in grooves in sand or on tablets of wood, stone, or metal. The abacus was in use centuries before the adoption of the written modern numeral system and is still widely used by merchants, traders and clerks in Asia, Africa, and elsewhere. The user of an abacus is called an abacist.
The use of the word abacus dates before 1387 AD, when a Middle English work borrowed the word from Latin to describe a sandboard abacus. The Latin word came from Greek ἄβαξ abax "board strewn with sand or dust used for drawing geometric figures or calculating"(the exact shape of the Latin perhaps reflects the genitive form of the Greek word, ἄβακoς abakos). Greek ἄβαξ itself is probably a borrowing of a Northwest Semitic, perhaps Phoenician, word akin to Hebrew ʾābāq (אבק), "dust" (since dust strewn on wooden boards to draw figures in). The preferred plural of abacus is a subject of disagreement, with both abacuses and
A sway bar or anti-roll bar or stabilizer bar is a part of an automobile suspension that helps reduce the body roll of a vehicle during fast cornering or over road irregularities. It connects opposite (left/right) wheels together through short lever arms linked by a torsion spring. A sway bar increases the suspension's roll stiffness—its resistance to roll in turns, independent of its spring rate in the vertical direction. The first stabilizer bar patent was awarded to the Canadian S. L. C. Coleman of Fredericton, New Brunswick on April 22, 1919.
An anti-sway or anti-roll bar is intended to force each side of the vehicle to lower, or rise, to similar heights, to reduce the sideways tilting (roll) of the vehicle on curves, sharp corners, or large bumps. With the bar removed, a vehicle's wheels can tilt away by much larger distances (as shown by the SUV image at right). Although there are many variations in design, a common function is to force the opposite wheel's shock absorber, spring or suspension rod to lower, or rise, to a similar level as the other wheel. In a fast turn, a vehicle tends to drop closer onto the outer wheels, and the sway bar will soon force the opposite wheel
A prime meridian is a meridian, i.e. a line of longitude, at which longitude is defined to be 0°. A prime meridian and its opposite in a 360°-system, the 180th meridian (at 180° longitude), form a great circle.
This great circle divides the sphere, e.g. the Earth, into two hemispheres. If one uses directions of East and West from a defined prime meridian, then they can be called Eastern Hemisphere and Western Hemisphere.
An international conference in 1884 decided the prime meridian passes through the Royal Observatory, Greenwich in southeast London, United Kingdom, known simply as the prime meridian but also sometimes referred to as the International Meridian or Greenwich meridian.
A prime meridian is ultimately arbitrary, unlike an equator, which is determined by the axis of rotation—and various conventions have been used or advocated in different regions and throughout history.
As of 2012 the most used prime meridian for the Earth is the IERS Reference Meridian (IRM). It passes about 5.3 arcseconds east of Airy's transit circle or about 102 metres (335 ft) at the latitude of the Royal Observatory, Greenwich, London. A current convention on the Earth uses the opposite of the IRM
Polymer banknotes were developed by the Reserve Bank of Australia (RBA), Commonwealth Scientific and Industrial Research Organisation (CSIRO) and The University of Melbourne and were first issued as currency in Australia in 1988. These banknotes are made from the polymer biaxially-oriented polypropylene (BOPP) which greatly enhances durability of the banknotes. Polymer banknotes also incorporate many security features not available to paper banknotes.
Trading as Securency, the RBA together with Innovia Films market BOPP as 'Guardian' for countries with their own banknote printing facilities. Note Printing Australia (a subsidiary of the RBA) prints commemorative banknotes and banknotes for circulation and has done so for 20 countries.
An alternative polymer of polyethylene fibres marketed as Tyvek by DuPont was developed for use as currency by the American Bank Note Company in the early 1980s. Tyvek did not perform well in trials; smudging of ink and fragility were reported as problems. Only Costa Rica and Haiti issued Tyvek banknotes; test notes were produced for Ecuador, El Salvador, Honduras and Venezuela but never placed in circulation. Additionally, English printers Bradbury
The Segway PT is a two-wheeled self-balancing battery-powered electric vehicle invented by Dean Kamen. It is produced by Segway Inc. of New Hampshire, USA. The name Segway is a homophone of the word segue, meaning "smooth transition"; PT denotes "personal transporter".
Computers and motors in the base of the device keep the Segway PT upright when powered on with balancing enabled. A user commands the Segway to go forward by shifting their weight forward on the platform, and backward by shifting their weight backward. The Segway detects, as it balances, the change in its center of mass, and first establishes and then maintains a corresponding speed, forward or backward. Gyroscopic sensors and fluid-based leveling sensors are used to detect the shift of weight. To turn, the user manipulates a control on the handlebar left or right.
Segway PTs are driven by electric motors and can go up to 12.5 miles per hour (20.1 km/h).
The Segway PT was known by the names Ginger and IT before it was unveiled. Ginger came out of the first product that used Kamen's balancing technology, the iBOT wheelchair. During development at the University of Plymouth, in conjunction with BAE Systems and Sumitomo
A lawn mower is a machine that uses a revolving blade or blades to cut a lawn at an even height.
Lawn mowers employing a blade that rotates about a vertical axis are known as rotary mowers, while those employing a blade assembly that rotates about a horizontal axis are known as cylinder or reel mowers.
Many designs have been made, each suited to a particular purpose. The smallest types, pushed by a human, are suitable for small residential lawns and gardens, while larger, self-contained, ride-on mowers are suitable for large lawns, and the largest, multi-gang mowers pulled behind a tractor, are designed for large expanses of grass such as golf courses and municipal parks.
The first lawn mower was invented by Edwin Budding in 1827 in Thrupp, just outside Stroud, in Gloucestershire. Budding's mower was designed primarily to cut the lawn on sports grounds and extensive gardens, as a superior alternative to the scythe, and was granted a British patent on August 31, 1830. It took ten more years and further innovations to create a machine that could be worked by animals, and sixty years before a steam-powered lawn mower was built. The first machine produced was 19 inches wide with a
A power loom is a mechanised loom powered by a line shaft. The first power loom was designed in 1784 by Edmund Cartwright and first built in 1785. It was refined over the next 47 years until a design by Kenworthy and Bullough made the operation completely automatic. This was known as the Lancashire Loom.
By 1850 there were 260,000 in operation in England. Fifty years later came the Northrop Loom that would replenish the shuttle when it was empty and this replaced the Lancashire loom.
The major components of the loom are the warp beam, heddles, harnesses, shuttle, reed and takeup roll. In the loom, yarn processing includes shedding, picking, battening and taking-up operations.
With each weaving operation, the newly constructed fabric must be wound on a cloth beam. This process is called taking up. At the same time, the warp yarns must be let off or released from the warp beams. To become fully automatic, a loom needs a filling stop motion which will brake the loom, if the weft thread breaks.
Rev Edmund Cartwright's invention of the power loom, this used water as power then steam power. it speeded up weaving process. weavers were able to use all the thread that spinners could
Curling is a sport in which players slide stones across a sheet of ice towards a target area which is segmented into four rings. It is related to bowls, boule and shuffleboard. Two teams, each of four players, take turns sliding heavy, polished granite stones, also called "rocks", across the ice curling sheet towards the house, a circular target marked on the ice. Each team has eight stones. The purpose is to accumulate the highest score for a game; points are scored for the stones resting closest to the centre of the house at the conclusion of each end, which is completed when both teams have thrown all of their stones. A game may consist of ten or eight ends.
The curler can induce a curved path by causing the stone to slowly turn as it slides, and the path of the rock may be further influenced by two sweepers with brooms who accompany it as it slides down the sheet, using the brooms to alter the state of the ice in front of the stone. A great deal of strategy and teamwork goes into choosing the ideal path and placement of a stone for each situation, and the skills of the curlers determine how close to the desired result the stone will achieve. This gives curling its nickname of
The Gilhoolie is a kitchen appliance that opens jars and bottles. It was invented by Dr. C. W. Fuller, a retired dentist from Yonkers, New York. The Gilhoolie debuted in 1953. It was patented in 1954 as a "cam operated sliding jaw closure remover".
A dump truck (or, UK, dumper truck) is a truck used for transporting loose material (such as sand, gravel, or dirt) for construction. A typical dump truck is equipped with a hydraulically operated open-box bed hinged at the rear, the front of which can be lifted to allow the contents to be deposited on the ground behind the truck at the site of delivery. In the UK and Australia the term applies to off-road construction plant only, and the road vehicle is known as a tipper, tipper lorry (UK) or tip truck (AU).
The dump truck is thought to have been first conceived in the farms of late 19th century Western Europe. As early as 1905, the first motorized dumping vehicles were developed. The first motorized dump trucks in the United States were developed by small equipment companies such as Galion Buggy Co. and Lauth-Juergens among many others around 1910. Such companies flourished during World War I due to massive wartime demand. Companies like Galion Buggy Co. continued to grow after the war by manufacturing a number of express bodies and some smaller dump bodies that could be easily installed on either stock or converted (heavy-duty suspension & drivetrain) Model T chassis prior to
The Geordie lamp was a safety lamp for use in flammable atmospheres, invented by George Stephenson in 1815 as a miner's lamp to prevent explosions due to firedamp in coal mines.
In 1815, Stephenson was the engine-wright at the Killingworth Colliery in Durham and had been experimenting for several years with candles close to firedamp emissions in the mine. In August he ordered an oil lamp which was delivered on 21 October and tested by him in the mine in the presence of explosive gases. He improved this over several weeks with the addition of capillary tubes at the base so that it gave more light and tried new versions on 4 and 30 November. This was presented to the Philosophical and Literary Society of Newcastle on 5 December 1815.
Although controversy arose between Stephenson's design and the Davy lamp (invented by Humphry Davy in the same year), Stephenson's original design worked on significantly different principles. If the only way air could get to the flame was restricted (a baseplate pierced by a number of small-bore brass tubes was the usual way of doing this) and the lamp body above the flame lengthened, then the same amount of air could get to the flame, but would pass
The Argand lamp is a home lighting oil lamp producing a light output of 6 to 10 candlepower which was invented and patented in 1780 by Aimé Argand. Aside from the improvement in brightness, the more complete combustion of the wick and oil required much less frequent snuffing (trimming) of the wick.
In France, they are known as "Quinquets" after Antoine-Arnoult Quinquet, a pharmacist in Paris, who used the idea originated by Argand and popularized it in France. He is sometimes credited with the addition of the glass chimney to the lamp.
The Argand lamp had a cylindrical candle wick mounted so that air can pass both through the center of the wick and also around the outside of the wick before being drawn into cylindrical chimney which steadies the flame and improves the flow of air. Early models used ground glass which was sometimes tinted around the wick.
An Argand lamp used whale oil, colza, olive oil or other vegetable oil as fuel which was supplied by a gravity feed from a reservoir mounted above the burner.
A disadvantage of the original Argand arrangement was that the oil reservoir needed to be above the level of the burner because the heavy, sticky vegetable oil would not rise
A steam locomotive is a railway locomotive that produces its power through a steam engine. These locomotives are fueled by burning some combustible material, usually coal, wood or oil, to produce steam in a boiler, which drives the steam engine. Both fuel and water supplies are carried with the locomotive, either on the locomotive itself or in wagons pulled behind.
Steam locomotives were first developed in Britain and dominated railway transportation until the middle of the 20th century. From the early 1900s they were gradually superseded by electric and diesel locomotives.
See also: History of rail transport, Category:Early steam locomotives
The earliest railways employed horses to draw carts along railed tracks.
As the development of steam engines progressed through the 18th century, various attempts were made to apply them to road and railway use. In 1784, William Murdoch, a Scottish inventor, built a prototype steam road locomotive. An early working model of a steam rail locomotive was designed and constructed by steamboat pioneer John Fitch in the United States probably during the 1780s or 1790s. His steam locomotive used interior bladed wheels guided by rails or tracks. The
The collodion process is an early photographic process, invented by Frederic Scott Archer. It was introduced in the 1850s and by the end of that decade it had almost entirely replaced the first practical photographic process, the daguerreotype. During the 1880s the collodion process, in turn, was largely replaced by gelatin dry plates—glass plates with a photographic emulsion of silver halides suspended in gelatin. The dry gelatin emulsion was not only more convenient but could be made much more sensitive, greatly reducing exposure times.
"Collodion process" is usually taken to be synonymous with the "collodion wet plate process", a very inconvenient form which required the photographic material to be coated, sensitized, exposed and developed within the span of about fifteen minutes, necessitating a portable darkroom for use in the field. Although collodion was normally used in this wet form, the material could also be used in humid ("preserved") or dry form, but at the cost of greatly increased exposure time, making these forms unsuitable for the usual work of most professional photographers—portraiture. Their use was therefore confined to landscape photography and other special
A flush toilet is a toilet that disposes of human waste by using water to flush it through a drainpipe to another location. Flushing mechanisms are found more often on western toilets (used in the sitting position), but many squat toilets also are made for automated flushing. Modern toilets incorporate an "S", "U", "J", or "P" shaped bend that causes the water in the toilet bowl to collect and act as a seal against sewer gases. Since flush toilets are typically not designed to handle waste on site, their drain pipes must be connected to waste conveyance and waste treatment systems. A flush toilet may be euphemistically called a lavatory, a pot (USA), a loo, a john, a water closet (abbreviated "W.C."), or simply "toilet".
As with many inventions, the flush toilet was the result of a long development. Therefore, instead of a single name and date, there follows a list of significant contributions to the history of the device.
The flushing mechanism provides a large flow of water into the bowl (which is described later in this article). The mechanism usually incorporates one or more parts of the following designs:
Tank fill valves are found in all tank-style toilets. The valves are of
For Diaphone, the Noctuid moth species see Diaphone (moth)
The diaphone was a noisemaking device best known for its use as a foghorn: it could produce deep, powerful tones able to carry a long distance. Diaphones were also used at some fire stations and in other situations where a loud audible signal was required.
The diaphone horn was based directly on the organ stop of the same name invented by Robert Hope-Jones, creator of the Wurlitzer organ. Hope-Jones' design, based on the vibrations in air created by a slotted piston moving within a correspondingly slotted cylinder, was adapted and patented by Professor John Pell Northey of the University of Toronto, who added a secondary compressed air supply to the piston to power it on both forward and reverse strokes and create an even more powerful sound. The entire horn apparatus was driven by a compressor.
To manufacture the new equipment, Northey set up the Diaphone Signal Co. at Toronto in 1903. It manufactured a range of diaphone models: the large "Type F", which created a tone of about 250 hertz, found worldwide use as a fog signal, especially in lighthouses. The mechanism of the diaphone created a noticeable low-frequency "grunt"
A seed drill is a sowing device that precisely positions seeds in the soil and then covers them. Before the introduction of the seed drill, the common practice was to plant seeds by hand. Besides being wasteful, planting was very imprecise and led to a poor distribution of seeds, leading to low productivity. The use of a seed drill can improve the ratio of crop yield by as much as nine times.
In older methods of planting, a field is initially prepared with a plough to a series of linear cuts known as furrows. The field is then seeded by throwing the seeds over the field, a method known as manual broadcasting. Seeds that landed in the furrows had better protection from the elements, and natural erosion or manual raking would preferentially cover them while leaving some exposed. The result was a field planted roughly in rows, but having a large number of plants outside the furrow lanes.
There are several downsides to this approach. The most obvious is that seeds that land outside the furrows will not have the growth shown by the plants sown in the furrow, since they are too shallow on the soil. Because of this, they are lost to the elements. Since the furrows represent only a portion
The Sinclair Research C5 is a battery electric vehicle invented by Sir Clive Sinclair and launched by Sinclair Vehicles Ltd in the United Kingdom on 10 January 1985. The vehicle is a battery-assisted tricycle steered by a handlebar beneath the driver's knees. Powered operation is possible making it unnecessary for the driver to pedal. Its top speed of 15 miles per hour (24 km/h), is the fastest allowed in the UK without a driving licence. It is powered by a 200w or 250W motor. It sold for £399 plus £29 for delivery.
It became an object of media and popular ridicule during 1980s Britain and was a commercial disaster, selling only around 17,000 units, although according to Sinclair, it was "the best selling electric vehicle" until November 2011 when the Nissan Leaf had sold over 20,000 units.
Sir Clive Sinclair started to think about electric vehicles as a teenager, and it was an idea he toyed with for decades. In the early 1970s Sinclair Radionics was working on the project. Sinclair had Chris Curry work on the electric motor. However, the company focus shifted to calculators and no further work was done on vehicles until the late 1970s. Development began again in 1979 and
The hot wire barretter was a demodulating detector, invented in 1902 by Reginald Fessenden, that found limited use in early radio receivers. In effect it was a highly sensitive thermoresistor developed to permit the reception of amplitude modulated signals, something that the coherer (the standard detector of the time) could not do.
The first device used to demodulate audio signals, it was later superseded by the electrolytic detector, also generally attributed to Fessenden. The barretter principle is still used as a detector for microwave radiation, similar to a bolometer.
An extremely fine platinum wire, about 0.003 inches (0.08 mm) in diameter, is embedded in the middle of a silver wire having a diameter of about 0.1 inches (2.5 mm). This compound wire is then drawn until the silver wire had a diameter of about 0.002 inches (0.05 mm); as the platinum wire within it is reduced in the same ratio, it is drawn down to a final diameter of 0.00006 inches (1.5 µm). The result is called Wollaston wire.
The silver cladding is etched off a short piece of the composite wire, leaving an extremely fine platinum wire; this is supported, on two heavier silver wires, in a loop inside a glass
Neuticles are prosthetic testicular implants for neutered dogs and other domestic animals. Creator Gregg Miller won the 2005 Ig Nobel Prize in Medicine, a parody of the real Nobel Prize, for his invention. As of September 2007, more than 240,000 pairs of the patented product had been sold, in all 50 U.S. states and 49 countries.
scher developed the idea for Neuticles in 1993, after his bloodhound Buck caught the scent of a bitch in heat, disappeared and turned up days later 30 miles away. Miller had Buck neutered to stop his wandering. Following the procedure, when Buck went to clean himself, he realized something was missing and acted "extremely depressed" for three days.
The first commercial Neuticles were implanted in 1995. Neuticles are made from Food and Drug Administration–approved materials and are designed to replicate the weight and feel of the animal's natural testicles. They are made of solid silicone and are not gel-filled and therefore cannot leak.
Several companies have tried to copy the patented prosthetic. In a June 2000 press release, CTI Corporation, which manufactures Neuticles, cited an investigation revealing that companies in New York and California were
A rocket stove is an efficient cooking stove using small diameter wood fuel which is burned in a simple high-temperature combustion chamber containing an insulated vertical chimney which ensures complete combustion prior to the flames reaching the cooking surface. The principles were described by Dr. Larry Winiarski from Aprovecho in 1982 and stoves based on this design won Ashden Awards in both 2005 and 2006. Interest in rocket stoves has led to the development of rocket mass heaters and other innovations.
A rocket stove achieves efficient combustion of the fuel at a high temperature by ensuring a good air draft into the fire, controlled use of fuel, complete combustion of volatiles, and efficient use of the resultant heat. It has been used for cooking purposes in many third-world locales (notably Rwandan refugee camps) as well as for space and water heating.
A rocket stove's main components are:
The fuel magazine can be horizontal, where additional fuel will be added manually, or vertical, for automatic feeding of fuel. As the fuel burns within the combustion chamber, convection draws new air into the combustion chamber from below, ensuring that any smoke from smoldering wood
Cordite is a family of smokeless propellants developed and produced in the United Kingdom from 1889 to replace gunpowder as a military propellant. Like gunpowder, cordite is classified as a low explosive because of its slow burning rates and consequently low brisance. These produce a subsonic deflagration wave rather than the supersonic detonation wave produced by brisants, or high explosives. The hot gases produced by burning gunpowder or cordite generate sufficient pressure to propel a bullet or shell to its target, but not enough to destroy the barrel of the firearm, or gun.
Cordite was used initially in the .303 British, Mark I and II, standard rifle cartridge between 1891 and 1915; however, shortages of cordite in World War I led to United States–developed smokeless powders being imported into the UK for use in rifle cartridges. Cordite was also used for large weapons, such as tank guns, artillery and naval guns. It has been used mainly for this purpose since the late 19th century by the UK and British Commonwealth countries. Its use was further developed before World War II, and as 2-and-3-inch-diameter (51 and 76 mm) Unrotated Projectiles for launching anti-aircraft weapons.
A flight data recorder (FDR) (also ADR, for accident data recorder) is an electronic device employed to record any instructions sent to any electronic systems on an aircraft. It is a device used to record specific aircraft performance parameters. Another kind of flight recorder is the cockpit voice recorder (CVR), which records conversation in the cockpit, radio communications between the cockpit crew and others (including conversation with air traffic control personnel), as well as ambient sounds. In this both functions have been combined into a single unit. The current applicable FAA TSO is C124b titled Flight Data Recorder Systems.
Popularly referred to as a "black box" by the media, the data recorded by the FDR is used for accident investigation, as well as for analyzing air safety issues, material degradation and engine performance. Due to their importance in investigating accidents, these ICAO-regulated devices are carefully engineered and stoutly constructed to withstand the force of a high speed impact and the heat of an intense fire. Contrary to the "black box" reference, the exterior of the FDR is coated with heat-resistant bright orange paint for high visibility in
A snap fastener (also called snap, popper, and press stud) is a pair of interlocking discs commonly used in place of buttons to fasten clothing. A circular lip under one disc fits into a groove on the top of the other, holding them fast until a certain amount of force is applied. Snap fasteners are often used in children's clothing, as they are relatively easy for children to use.
Snaps can be attached to fabric by hammering (using a specific punch and die set), plying, or sewing. For plying snap fasteners, there are special snap pliers.
In the famous Chinese Terracotta Army, dating from 210 BCE, the horse halters of wagons, made of a gold tube and a silver tube, were joined with a form of snap fasteners.
Snap fasteners were first patented by German inventor Heribert Bauer in 1885 as the "Federknopf-Verschluss", a novelty fastener for men's trousers. Some attribute the invention to Bertel Sanders, of Denmark. These first versions featured an S-shaped spring in the top disc instead of a groove. However, it was not until Jack Weil (1901–2008) modified the design and put snaps on his iconic Western shirts that the term "snap" became commonplace and that snaps became a feature of much
A steam hammer is a power hammer driven by steam, used to shape forgings. It consists of a hammer-like piston located within a cylinder. The hammer is raised by the pressure of steam injected into the lower part of a cylinder and falls down with a force by removing the steam. Usually, the hammer is made to fall faster by injecting steam into the upper part of the cylinder. Steam hammers that fall by their own weight are called steam drop hammers. Steam hammers vary greatly in weight from 45 kilograms to 90 metric tons.
The steam hammer was invented around 1837 by the Scot James Nasmyth, in Manchester, England and produced in his Patricroft foundry which he built adjacent to the (then new) Liverpool and Manchester Railway and the Bridgewater Canal. From the first, Nasmyth's steam hammer could vary the force of the blow within a very wide range. He was fond of showing how he could break an egg placed in a wineglass without breaking the glass, which was followed by a blow that shook the building.
An original Nasmyth hammer stands facing his foundry buildings (now a 'business park'). A larger Nasmyth & Wilson steam hammer stands in the campus of the University of Bolton.
The stencil duplicator or mimeograph machine (often abbreviated to mimeo) is a low-cost printing press that works by forcing ink through a stencil onto paper. The mimeograph process should not be confused with the spirit duplicator process.
Mimeographs, along with spirit duplicators and hectographs, were a common technology in printing small quantities, as in office work, classroom materials, and church bulletins. Early fanzines were printed in this technology, because it was widespread and cheap. In the late 1960s, mimeographs, spirit duplicators, and hectographs were gradually displaced by photocopying and offset printing.
Thomas Edison received US patent 180,857 for "Autographic Printing" on August 8, 1870. The patent covered the electric pen, used for making the stencil, and the flatbed duplicating press. In 1880 Edison obtained a further patent, US 224,665: "Method of Preparing Autographic Stencils for Printing", which covered the making of stencils using a file plate, a grooved metal plate on which the stencil was placed which perforated the stencil when written on with a blunt metal stylus.
The word "mimeograph" was first used by Albert Blake Dick when he licensed Edison's
A tire (in American English and Canadian English) or tyre (in some Commonwealth Nations such as UK, Australia and New Zealand) is a ring-shaped covering that fits around a wheel rim to protect it and enable better vehicle performance by providing a flexible cushion that absorbs shock while keeping the wheel in close contact with the ground. The word itself may be derived from the word "tie," which refers to the outer steel ring part of a wooden cart wheel that ties the wood segments together (see Etymology below).
The fundamental materials of modern tires are synthetic rubber, natural rubber, fabric and wire, along with other compound chemicals. They consist of a tread and a body. The tread provides traction while the body ensures support. Before rubber was invented, the first versions of tires were simply bands of metal that fitted around wooden wheels to prevent wear and tear. Today, the vast majority of tires are pneumatic inflatable structures, comprising a doughnut-shaped body of cords and wires encased in rubber and generally filled with compressed air to form an inflatable cushion. Pneumatic tires are used on many types of vehicles, such as cars, bicycles, motorcycles,
Bird's Custard is the brand name for the first powdered, egg-free custard. Custard powder or Instant custard powder are the generic product names for similar and competing products. It is a cornflour (US cornstarch)-based powder which thickens to form a custard-like sauce when mixed with milk and heated to a sufficient temperature. Bird's Custard was first formulated and first cooked by Alfred Bird in 1837, because his wife was allergic to eggs, the key ingredient used to thicken traditional custard.
In some regions, such as Australia and the United Kingdom, the popularity of this type of dessert is such that it is simply known as "custard". In such cases, general usage of the word may be more likely to refer to the "Bird's" custard rather than to the traditional egg-based variety.
Bird's Custard and other brands mimicking its composition are also popular in India, where a large portion of the populace follows a vegetarian diet, although Ovo-lacto variants are also available.
In recent years, "instant" versions (containing powdered milk and sugar and requiring only hot water) and ready-made custard in tins, plastic pots and cartons have also become popular.
A food and drink survey
The Globotype is a color display for telecommunications. It was invented and patented by David McCallum of Stonehouse, Devon, England. The device features very low cost and does not use consumable supplies. It is Royal Letters Patent No. 2924 issued December 29, 1855. The design and coding used is described in Froehlich/Kent Encyclopedia of Telecommunications, Volume 2, pages 461 and 462. Mr. McCallum invented the Globotype in response to the use of printing telegraph machines which he saw as both expensive and unneeded.
"They are all very ingeniously contrived ... but why attach such combersome expensive machinery for the purpose of printing the letters? If a message must be printed, why not have a man in the office do it? He will do it better than it can be done by galvanic power attached to a telegraph wire, etc. etc." -David McCallum
The inventor published a small booklet in 1856 entitled: THE GLOBOTYPE TELEGRAPH: A recording instrument, by which small coloured balls are released one-by-one, and made to pass over a series of inclined planes, by the force of their own gravity. The booklet was originally published by Longman, Brown, Green, and Longmans of London.
It is cited and
A MOB boat is a small, fast rescue boat which large vessels, especially passenger ferries and cruise ships, use for Man overboard situations. A MOB boat often has a RIB or similar hull to achieve great speed with stability. Both outboard engines and inboard pump-jet propulsion is used on MOB boats. A MOB boat is required to be able to be launched and retrieved quickly, and is usually lowered with one wire.
A Tree shelter, or tree guard, is a type of plastic shelter used to nurture trees in the early stages of their growth. Tree shelters are also sometimes known as Tuley tubes or tree tubes.
Tree shelters protect young trees from browsing by most herbivores by forming a physical barrier along with providing a barrier to chemical spray applications. Additionally, tree Tubes (tree shelters) accelerate growth by providing a mini-greenhouse environment that reduces moisture stress, channels growth into the main stem and roots and allows efficient control of weeds that can rob young seedlings of soil moisture and sunlight.
An alternative to a traditional tree shelter is something called a Spiral Guard. These are coiled lengths of PVC in various diameters, lengths and colors. Manufactured from 100% recycled PVC, these are an economical and environmentally friendly means of protecting young trees from browsing wildlife and harsh conditions, at the same time preventing scrap plastics being sent to landfill sites.
They are particularly popular in the UK in landscape-scale planting schemes, but their importance has been established in the United States since 2000. About 1 million shelters were
A hovercraft, also known as an air-cushion vehicle or ACV, is a craft capable of travelling over land, water, mud or ice and other surfaces both at speed and when stationary. Hovercraft are hybrid vessels operated by a pilot as an aircraft rather than a captain as a marine vessel.
They operate by creating a cushion of high-pressure air between the hull of the vessel and the surface below. Typically this cushion is contained within a flexible "skirt". They typically hover at heights between 200mm and 600mm above any surface and operate above 20 knots and can clear gradients up to 20 degrees.
The first practical design for hovercraft derived from a British invention in the 1950s to 1960s. They are now used throughout the world as specialised transports in disaster relief, coastguard, military and survey applications as well as for sport or passenger service. Very large versions have been used to transport hundreds of people and vehicles across the English Channel whilst others have military applications used to transport tanks, soldiers and large equipment in hostile environments and terrain.
There have been many attempts to understand the principles of high air pressure below hulls
Microforms are any forms, either films or paper, containing microreproductions of documents for transmission, storage, reading, and printing. Microform images are commonly reduced to about one twenty-fifth of the original document size. For special purposes, greater optical reductions may be used.
All microform images may be provided as positives or negatives, more often the latter.
Three formats are common: microfilm (reels), aperture cards and microfiche (flat sheets). Microcards, a format no longer produced, were similar to microfiche, but printed on cardboard rather than photographic film.
Using the daguerreotype process, John Benjamin Dancer was one of the first to produce microphotographs, in 1839. He achieved a reduction ratio of 160:1. Dancer perfected his reduction procedures with Frederick Scott Archer’s wet collodion process, developed in 1850–51, but he dismissed his decades-long work on microphotographs as a personal hobby, and did not document his procedures. The idea that microphotography could be no more than a novelty was an opinion shared by the 1858 Dictionary of Photography, which called the process "somewhat trifling and childish."
Microphotography was first
Gecko tape (with directional adhesion) is a new material still at the developmental stage. Directional adhesion refers to the ability of an adhesive material to grip a load in one direction and to release its grip when the direction is reversed.
Gecko tape, an example of biomimicry, is so called because it is based on the ability of the gecko to adhere to surfaces – regardless of a surface's orientation – due to millions of microscopic hairs, called setae, on the gecko's toes.
There are also a number of insects that achieve adhesion based on the same principles as the gecko.
Due to a very close contact of the spatulae (very small hairs in the setae), the common thought is that [Van der Waals force|Van der Waals] interactions are involved. Usually there are only Van der Waals interactions in the same material (solids). Because of the very small hairs, a close contact is achieved, which leads to the Van der Waals interaction. This interaction is not very big because the hairs are just small. The large number of hairs makes the total Van der Waals force large. The force can only work with macro angles smaller than 30 degrees. With these small angles, a normal static friction leads to
Metrocable is a gondola lift system implemented by the City Council of Medellín, Colombia with the purpose of providing a complementary transportation service to that of Medellín's Metro. It was designed to reach some of the least developed suburban areas of Medellín. and is largely considered to be the first Cable Propelled Transit system at South America. The initial conception of this system was indirectly inspired by the Caracas Aerial Tramway (also known as the Mount Avila Gondola) which was designed primarily to carry passengers to a luxury hotel.
As of 2010, the Medellin Metrocable system contained three lines, namely Line K, Line J and Line L (Cable Arvi). Overall, the system has been received with enthusiasm by the locals.
Medellín is a city located in the Aburra Valley and it is therefore surrounded by hills. Many of those hills are home to underdeveloped barrios (comunas), which due to their location cannot be reached by Medellín's biggest mass transportation system Metro. Many of these barrios are in fact located in very steep grounds to the extent that not even a regular bus system could be either useful or commercially profitable. Before the implementation of the
The bombe was an electromechanical device used by British cryptologists to help decipher German Enigma-machine-encrypted signals during World War II. The US Navy and US Army later produced machines to the same functional specification, but engineered differently.
The initial design of the bombe was produced in 1939 at the UK Government Code and Cypher School at Bletchley Park by Alan Turing, with an important refinement devised in 1940 by Gordon Welchman. The engineering design and construction was the work of Harold Keen of the British Tabulating Machine Company. It was a substantial development from a device that had been designed in 1938 by Polish Cipher Bureau cryptologist Marian Rejewski, and known as the "cryptologic bomb" (Polish: "bomba kryptologiczna").
The function of the bombe was to discover some of the daily settings of the Enigma machines on the various German military networks: specifically, the set of rotors in use and their positions in the machine; the rotor core start positions for the message—the message key—and one of the wirings of the plugboard.
The Enigma was an electro-mechanical rotor machine used for the encryption and decryption of secret messages. It
The cat's eye is a retroreflective safety device used in road marking and was the first of a range of raised pavement markers. It originated in the UK in 1933 and is today used all over the world.
It consists (in its original form) of two pairs of reflective glass spheres set into a white rubber dome, mounted in a cast iron housing. This is the kind that marks the centre of the road, with one pair of cat's eyes showing in each direction. A single-ended form has become widely used in other colours at road margins and as lane dividers. Cat's eyes are particularly valuable in fog and are largely resistant to damage from snow ploughs.
A key feature of the cat's eye is the flexible rubber dome which is occasionally deformed by the passage of traffic. A fixed rubber wiper cleans the surface of the reflectors as they sink below the surface of the road (the base tends to hold water after a shower of rain, making this process even more efficient). The rubber dome is protected from impact damage by metal 'kerbs' – which also give tactile and audible feedback for wandering drivers.
The inventor of cat's eyes was Percy Shaw of Boothtown, Halifax, West Yorkshire, England. When the tram-lines
Puffing Billy is an early railway steam locomotive, constructed in 1813-1814 by engineer William Hedley, enginewright Jonathan Forster and blacksmith Timothy Hackworth for Christopher Blackett, the owner of Wylam Colliery near Newcastle upon Tyne, in the United Kingdom. It is the world's oldest surviving steam locomotive. It was the first commercial adhesion steam locomotive, employed to haul coal chaldron wagons from the mine at Wylam to the docks at Lemington-on-Tyne in Northumberland.
Puffing Billy was one of the three similar engines built by Hedley, the resident engineer at Wylam Colliery, to replace the horses used as motive power on the tramway. In 1813 Hedley built for Blackett's colliery business on the Wylam Colliery line the prototypes, "Puffing Billy" and "Wylam Dilly". They were both rebuilt in 1815 with ten wheels, but were returned to their original condition in 1830 when the railway was relaid with stronger rails.
Puffing Billy remained in service until 1862, Edward Blackett, the owner of Wylam Colliery, lent it to the Patent Office Museum in South Kensington, London (later the Science Museum). He later sold it to the museum for £200. It is still on display there.
The Bessemer process was the first inexpensive industrial process for the mass-production of steel from molten pig iron. The process is named after its inventor, Henry Bessemer, who took out a patent on the process in 1855. The process was independently discovered in 1851 by William Kelly. The process had also been used outside of Europe for hundreds of years, but not on an industrial scale. The key principle is removal of impurities from the iron by oxidation with air being blown through the molten iron. The oxidation also raises the temperature of the iron mass and keeps it molten.
The process using a basic refractory lining is known as the basic Bessemer process or Gilchrist-Thomas process after the discoverer Sidney Gilchrist Thomas.
The oxidation process removes and skims off impurities such as silicon, manganese, and carbon in the form of oxides. These oxides either escape as gas or form a solid slag. The refractory lining of the converter also plays a role in the conversion—the clay lining is used in the acid Bessemer, in which there is low phosphorus in the raw material. Dolomite is used when the phosphorus content is high in the alkaline Bessemer (limestone or magnesite
A bin bag, swag sack or bin liner (British English) or garbage bag or trash bag (American English) is a disposable bag used to contain rubbish (British English) or trash (American English). Such bags are useful to line the insides of waste containers to prevent the insides of the receptacle from becoming coated in waste material. Most bags these days are made out of plastic, and are typically green or black in color.
Plastic bags are a convenient and sanitary way of handling garbage, and are widely used. Plastic garbage bags are fairly lightweight and are particularly useful for messy or wet rubbish, as is commonly the case with food waste, and are also useful for wrapping up garbage to minimize odour. Plastic bags are often used for lining litter or waste containers or bins. This serves to keep the container sanitary by avoiding container contact with the garbage. After the bag in the container is filled with litter, the bag can be pulled out by its edges, closed, and tied with minimal contact with the waste matter.
Created in 1950, this invention can be attributed to Canadians Harry Wasylyk, Larry Hansen and Frank Plomp. In a recent special on CBC television, the green garbage
A flame ionization detector (FID) is a type of gas detector used in gas chromatography. The first flame ionization detector was developed in 1957 by scientists working for the CSIRO in Melbourne, Australia.
The detection of organic compounds is most effectively done with flame ionization. Biochemical compounds such as proteins, nucleotides, and pharmaceuticals can be studied with flame ionization as well as other detectors, like thermal conductivity, thermionic, or electrolytic conductivity due to the presence of nitrogen, phosphorus, or sulfur atoms or because of the universality of the thermal conductivity detector. However, typically the biochemical compounds have a greater amount of carbon present than other elements. This means that a particular compound may be more easily detected using flame ionization over the other methods because of higher carbon concentration and also flame ionization's sensitivity.
This selectivity can be a problem or an advantage. For example, an FID is excellent for detecting methane in nitrogen, since it would respond to the methane but not to the nitrogen.
FIDs are best for detecting hydrocarbons and other easily flammable components. They are very
A hydraulophone is a tonal acoustic musical instrument played by direct physical contact with water (sometimes other fluids) where sound is generated or affected hydraulically. Typically sound is produced by the same hydraulic fluid in contact with the player's fingers. The term also refers to an acoustic sound-producing mechanism used as an interface or input device involving the monitoring of fluid flow. Examples include hydraulophones for fluid-flow monitoring and measurement applications, such as building automation, equipment monitoring, and the like (for example, determining which faucet or toilet in a building is operating and how much water it is consuming). The hydraulophone in the first sense was invented and named by Steve Mann.
The term may be applied based on the interface used to play the instrument, in which a player blocks the flow of water through a particular hole in order to sound a particular note, or based on a hydraulic sound production mechanism. Hydraulophones use water flow sound producing mechanisms. They have a user interface, which is blocking water jets to produce sound. Those described in Mann's paper Hydraulophone design considerations use water jets
Macadam is a type of road construction pioneered by Scottish engineer John Loudon McAdam in around 1820. The method simplified what had been considered state of the art at that point. Single-sized aggregate layers of small stones, with a coating of binder as a cementing agent, are mixed in an open-structured roadway.
Pierre-Marie-Jérôme Trésaguet is sometimes considered the first person to bring science to road building. A Frenchman from an engineering family, he worked paving roads in Paris from 1757 to 1764. As chief engineer of road construction of Limoges he had opportunity to develop a better and cheaper method of road construction. In 1775 Tresaguet became engineer-general and presented his answer for road improvement in France, which soon became standard practice there.
Trésaguet had recommended a roadway consisting of three layers of stones laid on a crowned subgrade with side ditches for drainage. The first two layers consisted of angular hand-broken aggregate, maximum size 3 inches (76 mm), to a depth of about 8 inches (203 mm). The third layer was about 2 inches (51 mm) thick with a maximum aggregate size of 1 inch (25 mm). This top level surface permitted a smoother
An operant conditioning chamber (also known as the Skinner box) is a laboratory apparatus used in the experimental analysis of behavior to study animal behavior. The operant conditioning chamber was created by B. F. Skinner while he was a graduate student at Harvard University (Masters in 1930 and doctorate in 1931). It is used to study both operant conditioning and classical conditioning.
An operant conditioning chamber permits experimenters to study behavior conditioning (training) by teaching a subject animal to perform certain actions (like pressing a lever) in response to specific stimuli, like a light or sound signal. When the subject correctly performs the behavior, the chamber mechanism delivers food or another reward. In some cases, the mechanism delivers a punishment for incorrect or missing responses. With this apparatus, experimenters perform studies in conditioning and training through reward/punishment mechanisms.
The structure forming the shell of a chamber is a box large enough to easily accommodate the animal being used as a subject. (Commonly used model animals include rodents—usually lab rats—pigeons, and primates). It is often sound-proof and light-proof to
Bindeez (also marketed as Aqua Dots, Beados, and Pixos) are a children's toy that was awarded Australian "Toy of the Year" for 2007. Toy Wishes magazine named it as one of the products among its 12 best toys of 2007. It is manufactured in China for the Australian-owned company Moose Enterprise P/L, and distributed in North America by Spin Master Ltd. It is distributed in 40 countries, and 12 million packets, containing more than 8 billion beads, have been sold worldwide.
The toy was subject to a multi-national product recall after it was found that the Wangqi Product Factory in Shenzhen, China had used a cheap chemical that was a pharmacologically active sedative prodrug instead of the safer specified one in some shipped toys, resulting in the illness and hospitalization of some children who ingested the beads.
Bindeez contains a craft kit that allows children to create various multi-dimensional designs using small colored beads. "Bindeez" can refer to either the toy itself or the small beads. The beads are arranged into various designs on a plastic tray. When the beads are sprayed with water, their surfaces become adhesive and they fuse together. The beads are then left to dry and
The Gregorian telescope is a type of reflecting telescope designed by Scottish mathematician and astronomer James Gregory in the 17th century, and first built in 1673 by Robert Hooke. The design pre-dates the first practical reflecting telescope, the Newtonian telescope, built by Sir Isaac Newton in 1668, but was not successfully built until 5 years after Newton's first reflecting telescope.
The Gregorian telescope is named after the James Gregory design which appeared in his 1663 publication Optica Promota (The Advance of Optics). Similar theoretical designs have been found in the writings of Bonaventura Cavalieri (Lo Specchio Ustorio (On Burning Mirrors), 1632) and Marin Mersenne (l"Harmonie universalle, 1636). Gregory's early attempts to build the telescope failed, since he had no practical skill himself and he could find no optician capable of actually constructing one. It was not until ten years after Gregory's publication, aided by the interest of experimental scientist Robert Hooke, that a working instrument was created.
The Gregorian telescope consists of two concave mirrors; the primary mirror (a concave paraboloid) collects the light and brings it to a focus before the
An adjustable spanner or adjustable wrench is a spanner with a "jaw" of adjustable width, allowing it to be used with different sizes of fastener head (nut, bolt, etc.) rather than just one fastener, as with a conventional fixed spanner. An adjustable spanner may also be called a shifting spanner, shifting adjustable, shifter, fit-all, crescent wrench (incorrect usage - see Famous brands section), adjustable angle-head wrench or Bahco (see below).
In many European countries (e.g. France, Germany, Portugal, Spain and Italy) the adjustable spanner is called an "English key" as it was first invented in 1842 by the English engineer Richard Clyburn. Another English engineer, Edwin Beard Budding, is also credited with the invention. Improvements followed: on 22 September 1885 Enoch Harris received US patent 326868 for his spanner that permitted both the jaw width and the angle of the handles to be adjusted and locked. Other countries, like Denmark, Poland and Israel, refer to it as a "Swedish key" as its invention has been attributed to the Swedish inventor Johan Petter Johansson, who in 1891 received a patent for an improved design of the adjustable spanner that is still used today.
The cloud chamber, also known as the Wilson chamber, is a particle detector used for detecting ionizing radiation.
In its most basic form, a cloud chamber is a sealed environment containing a supersaturated vapor of water or alcohol. When a charged particle (for example, an alpha or beta particle) interacts with the mixture, it ionizes it. The resulting ions act as condensation nuclei, around which a mist will form (because the mixture is on the point of condensation). The high energies of alpha and beta particles mean that a trail is left, due to many ions being produced along the path of the charged particle. These tracks have distinctive shapes (for example, an alpha particle's track is broad and shows more evidence of deflection by collisions, while an electron's is thinner and straight). When any uniform magnetic field is applied across the cloud chamber, positively and negatively charged particles will curve in opposite directions, according to the Lorentz force law with two particles of opposite charge
Cloud chambers played a prominent role in the experimental particle physics from 1920s to the 1950s, until the advent of the bubble chamber. In particular, the discoveries of
A corkscrew is a kitchen tool for drawing corks from wine bottles. Generally, a corkscrew consists of a pointed metallic helix (often called the "worm") attached to a handle. The user grips the handle and screws the metal point into the cork, until the helix is firmly embedded, then a vertical pull on the corkscrew extracts the cork from the bottle. Corkscrews are necessary because corks themselves, being small and smooth, are difficult to grip and remove, particularly when inserted fully into an inflexible glass bottle. The handle of the corkscrew, often a horizontal bar of wood attached to the screw, allows for a commanding grip to ease removal of the cork. Corkscrew handles may incorporate levers that further increase the amount of force that can be applied outwards upon the cork.
Its design may have derived from the gun worm which was a device used by musketmen to remove unspent charges from a musket's barrel in a similar fashion, from at least the early 1630s.
The corkscrew is possibly an English invention, due to the tradition of beer and cider, and Treatise on Cider by John Worlidge in 1676 describes "binning of tightly corked cider bottles on their sides", although the
A gas turbine, also called a combustion turbine, is a type of internal combustion engine. It has an upstream rotating compressor coupled to a downstream turbine, and a combustion chamber in-between.
Energy is added to the gas stream in the combustor, where fuel is mixed with air and ignited. In the high pressure environment of the combustor, combustion of the fuel increases the temperature. The products of the combustion are forced into the turbine section. There, the high velocity and volume of the gas flow is directed through a nozzle over the turbine's blades, spinning the turbine which powers the compressor and, for some turbines, drives their mechanical output. The energy given up to the turbine comes from the reduction in the temperature and pressure of the exhaust gas.
Energy can be extracted in the form of shaft power, compressed air or thrust or any combination of these and used to power aircraft, trains, ships, generators, or even tanks.
In 1930, having found no interest from the RAF for his idea, Frank Whittle patented the design for a centrifugal gas turbine for jet propulsion. The first successful use of his engine was in April 1937.
Gases passing through an ideal gas
The patent slip or Marine Railway was invented by Scot Thomas Morton in 1818 as a cheaper alternative to a dry dock for ship repair. It consisted of an inclined plane, which extended well into the water, and a wooden cradle onto which a ship was floated. The ship was then attached to the cradle and hauled out of the water up the slip.
In 1832, a House of Commons Select Committee, under the chairmanship of the, Rt. Hon. Sir George Cockburn, was convened to adjudicate on a petition by Thomas Morton to extend the duration of his patent. The committee eventually did not support the patent extension. It was claimed that not only was the cost of a slip one tenth of a dry dock but also by hauling completely onto a clear dry area that it was easier to carry out the maintenance.
Early designs would have used manpower and block and tackle to provide mechanical advantage, while later solutions used steam engines. One of the earliest surviving marine railways is the Creque Marine Railway on Hassel Island in the Caribbean.
The process of slipping a vessel is an easy, cheap and straightforward way to take a large vessel out of water for inspection or repair. In many cases, it is possible to take
An incandescent light bulb, incandescent lamp or incandescent light globe is an electric light which produces light with a filament wire heated to a high temperature by an electric current passing through it, until it glows (see Incandescence). The hot filament is protected from oxidation with a glass bulb that is filled with inert gas (or evacuated). In a halogen lamp, filament evaporation is prevented by a chemical process that redeposits metal vapor onto the filament, extending its life. The light bulb is supplied with electrical current by feed-through terminals or wires embedded in the glass. Most bulbs are used in a socket which provides mechanical support and electrical connections.
Incandescent bulbs are manufactured in a wide range of sizes, light output, and voltage ratings, from 1.5 volts to about 300 volts. They require no external regulating equipment, have low manufacturing costs, and work equally well on either alternating current or direct current. As a result, the incandescent lamp is widely used in household and commercial lighting, for portable lighting such as table lamps, car headlamps, and flashlights, and for decorative and advertising lighting.
Fax (short for facsimile), sometimes called telecopying, is the telephonic transmission of scanned printed material (both text and images), normally to a telephone number connected to a printer or other output device. The original document is scanned with a fax machine (or a telecopier), which processes the contents (text or images) as a single fixed graphic image, converting it into a bitmap, and then transmitting it through the telephone system. The receiving fax machine reconverts the coded image, printing a paper copy. Before digital technology became widespread, for many decades, the scanned data was transmitted as analog.
Although businesses usually maintain some kind of fax capability, the technology has faced increasing competition from Internet-based alternatives. Fax machines still retain some advantages, particularly in the transmission of sensitive material which, if sent over the Internet unencrypted, may be vulnerable to interception, without the need for telephone tapping. In some countries, because electronic signatures on contracts are not recognized by law while faxed contracts with copies of signatures are, fax machines enjoy continuing support in business.
The Franklin stove is a metal-lined fireplace named after its inventor, Benjamin Franklin. It was invented in 1741. It had a hollow baffle near the rear (to transfer more heat from the fire to a room's air) and relied on an "inverted siphon" to draw the fire's hot fumes around the baffle. It was intended to produce more heat and less smoke than an ordinary open fireplace. It is also known as a "circulating stove" or the "Pennsylvania fireplace".
The two distinguishing features of Franklin's stove were (1) a hollow baffle (i.e., a metal panel that directed the flow of the fire's fumes) and (2) a flue that acted as an inverted siphon.
In Franklin's stove, a hollow baffle was positioned inside and near the rear of the stove. The baffle was a wide but thin cast-iron box, which was open to the room's air at its bottom and at two holes on its sides, near its top. Air entered the bottom of the box and was heated both by the fire and by the fumes flowing over the front and back of the box. The warmed air then rose inside the baffle and exited through the holes in the baffle's sides.
The use of baffles to extract more heat from a fire and its fumes was not new. In 1618, Franz Kessler (ca.
The Frost Airship Glider was designed and constructed by William (Bill) Frost in the mid-1890s. According to the patent specification 1894-20431 issued in London, the craft was simply called 'A Flying Machine'.
The preamble to the specification states:
The flying machine is constructed with an upper and lower chamber of wire work covered with light waterproof material. Each chamber formed sharp at both ends with parallel side. The upper large chamber to contain sufficient gas to lift the machine. In the centre of upper chamber a cylinder is fixed in which a horizontal fan is driven by means of a shaft and bevelled gearing worked from the lower chamber.
According to local lore, Frost flew this machine for the only time on 24 September 1896 for an approximate distance of 500 metres, before coming down and crashing into bushes. A storm that night destroyed the craft and scattered the remains.
High explosive squash head (HESH) is a type of explosive ammunition that is effective against buildings and is also used against tank armour. It was fielded chiefly by the British Army as the main explosive round of its main battle tanks during the Cold War. It was also used by other military forces, particularly those that acquired the early post-World War 2 British 105 mm Centurion tank, including Sweden, India, and Israel. In the United States, it is known as HEP, for "High Explosive, Plastic". HESH rounds are thin metal shells filled with plastic explosive and a delayed-action base fuze. The plastic explosive is "squashed" against the surface of the target on impact and spreads out to form a disc or "pat" of explosive. The base fuze detonates the explosive milliseconds later, creating a shock wave that, owing to its large surface area and direct contact with the target, is transmitted through the material. In the case of the metal armor of a tank the compression shock wave is conducted through the armour to the point where it reaches the metal/air interface (the hollow crew compartment), where some of the energy is reflected as a tension wave. At the point where the compression
The Sarich orbital engine is a type of internal combustion engine, invented in 1972 by Ralph Sarich, an engineer from Perth, Australia, which features rotary rather than reciprocating motion of its internal parts. It differs from the conceptually similar Wankel engine by using a shaped rotor that rolls around the interior of the engine, rather than having a trilobular rotor that spins "in place".
The theoretical advantage is that there is no high-speed contact area with the engine walls, unlike in the Wankel engine in which edge wear is a problem. However, the combustion chambers are divided by blades which do have contact with both the walls and the rotor, and are said to have been difficult to seal due to the perpendicular intersection with the moving impeller.
Sarich worked on the concept for a number of years without ever producing a production engine. A prototype was demonstrated, running on the bench with no load. The engine, which produces very high revs, has only one moving part. It can supposedly be powered by compressed air or steam and can be run as a pump.
The Sarich orbital engine has a number of fundamental unsolved problems that have kept it from becoming a usable
The spinning frame is an Industrial Revolution invention for spinning thread or yarn from fibers such as wool or cotton in a mechanized way. It was developed in 18th-century Britain by Richard Arkwright and John Kay.
In 1760 England, yarn production from wool and cotton was still a cottage industry in which fibers were carded and spun by hand using a spinning wheel. As the textile industry expanded its markets and adopted faster machines, yarn supplies became scarce especially due to innovations such as the doubling of the loom speed after the invention of the flying shuttle. High demand for yarn spurred invention of the spinning jenny in 1765, followed closely by the invention of the spinning frame, later developed into the water frame (patented in 1769). Mechanisms had increased production of yarn so dramatically that by 1830 the yarn cottage industry in England could no longer compete and all spinning was carried out in factories.
Richard Arkwright employed John Kay to produce a new spinning machine that Kay had worked on with (or possibly stolen from) another inventor called Thomas Highs . With the help of other local craftsmen the team produced the spinning frame, which
The Transmission Control Protocol (TCP) is one of the core protocols of the Internet Protocol Suite. TCP is one of the two original components of the suite, complementing the Internet Protocol (IP), and therefore the entire suite is commonly referred to as TCP/IP. TCP provides reliable, ordered delivery of a stream of octets from a program on one computer to another program on another computer. TCP is the protocol used by major Internet applications such as the World Wide Web, email, remote administration and file transfer. Other applications, which do not require reliable data stream service, may use the User Datagram Protocol (UDP), which provides a datagram service that emphasizes reduced latency over reliability.
In May 1974 the Institute of Electrical and Electronic Engineers (IEEE) published a paper entitled "A Protocol for Packet Network Intercommunication." The paper's authors, Vint Cerf and Bob Kahn, described an internetworking protocol for sharing resources using packet-switching among the nodes. A central control component of this model was the Transmission Control Program that incorporated both connection-oriented links and datagram services between hosts. The
The water frame is the name given to the spinning frame, when water power is used to drive it. Both are credited to Richard Arkwright who patented the technology in 1768. It was based on an invention by Thomas Highs and the patent was later overturned. John Kay, a clock maker and mechanic who helped Highs build the spinning frame, sold the design to Arkwright (for what might be considered a derisory sum). It was Arkwright, however, who made the system work, realising that account had to be taken of the fibre lengths in the batch being spun.
The water frame is derived from the use of a water wheel to drive a number of spinning frames. The water wheel provided more power to the spinning frame than human operators, reducing the amount of human labour needed and increasing the spindle count dramatically. However, unlike the spinning jenny, the water frame could only spin one thread at a time until Samuel Crompton combined the two inventions into his spinning mule in 1779. However, the water frame could be assembled with hundreds of spinning heads in a single machine.
In 1771, Arkwright installed the water frame in his cotton mill at Cromford, Derbyshire, on the River Derwent, creating
Calcium aluminate cements are cements consisting predominantly of hydraulic calcium aluminates. Alternative names are "aluminous cement", "high-alumina cement" and "Ciment fondu" in French. They are used in a number of small-scale, specialized applications.
The method of making cement from limestone and low-silica bauxite was patented in France in 1908 by Bied of the Pavin de Lafarge Company. The initial development was as a result of the search for a cement offering sulfate resistance. The cement was called in the French "Ciment fondu". Subsequently, its other special properties were discovered, and these guaranteed its future in niche applications.
The main active constituent of calcium aluminate cements is monocalcium aluminate (CaAl2O4, CaO · Al2O3, or CA in the cement chemist notation). It usually contains other calcium aluminates as well as a number of less reactive phases deriving from impurities in the raw materials. Rather a wide range of compositions is encountered, depending on the application and the purity of aluminium source used. Constituents of some typical formulations include:
The mineral phases all take the form of solid solutions with somewhat variable
Cream soda is a high-calorie sweet carbonated soft drink, often flavored with vanilla.
A recipe for cream soda—written by E.M. Sheldon and published in Michigan Farmer in 1852—called for water, cream of tartar, Epsom salts, sugar, tartaric acid, egg, and milk, to be mixed, then heated, and when cool mixed with water and a quarter teaspoonful of soda (sodium bicarbonate) to make an effervescent drink.
Alexander C. Howell, of Vienna, New Jersey, was granted a patent for "cream soda-water" on June 27, 1865. Howell's cream soda-water was made with sodium bicarbonate, water, sugar, egg whites, wheat flour, and "any of the usual flavoring materials—such as oil of lemon, &c, extracts of vanilla, pine-apple, &c., to suit the taste"; before drinking, the cream soda water was mixed with water and an acid such as tartaric acid or citric acid. In Canada, James William Black of Berwick, Nova Scotia was granted a U.S. patent on December 8, 1885, and a Canadian patent on July 5, 1886, for "ice-cream soda". Black's ice-cream soda, which contained whipped egg whites, sugar, lime juice, lemons, citric acid, flavoring, and bicarbonate of soda, was a concentrated syrup that could be reconstituted into
Gore-Tex is a waterproof/breathable fabric, and a registered trademark of W. L. Gore and Associates. It was co-invented by Wilbert L. Gore, Rowena Taylor, and Gore's son, Robert W. Gore. Robert Gore was granted U.S. Patent 3,953,566 on April 27, 1976, for a porous form of polytetrafluoroethylene (the chemical constituent of Teflon) with a micro-structure characterized by nodes interconnected by fibrils. Robert Gore, Rowena Taylor, and Samuel Allen were granted U.S. Patent 4,194,041 on March 18, 1980 for a "waterproof laminate." For its invention, Robert W. Gore was inducted into the US National Inventors Hall of Fame in 2006.
In 1966, John W. Cropper of New Zealand developed and constructed a machine for producing stretched polytetrafluoroethylene (PTFE) tape. Rather than file for a patent, however, Cropper chose to keep the process of creating expanded PTFE as a closely held trade secret and required his producer and its employees to sign confidentiality agreements.
In 1969, Bob Gore independently discovered expanded polytetrafluoroethylene (ePTFE) and introduced it to the public under the trademark Gore-Tex, for which he promptly applied for and obtained U.S. Patent 3,953,566,
The gridiron pendulum was an improved clock pendulum invented by British clockmaker John Harrison around 1726. It didn't change its effective length with temperature, so its period of swing stayed constant with changes in ambient temperature. It consisted of alternating brass and iron rods arranged so that their different thermal expansions (or contractions) counteracted each other.
Its simplest and later form consists of five rods. A central iron rod runs up from the bob to a point immediately below the suspension. At that point a cross-piece (middle bridge) extends from the central rod and connects to two zinc rods, one on each side of the central rod, which reach down to, and are fixed to, the bottom bridge just above the bob. The bottom bridge clears the central rod and connects to two further iron rods which run back up to the top bridge attached to the suspension. As the iron rods expand in heat, the bottom bridge drops relative to the suspension, and the bob drops relative to the middle bridge. However, the middle bridge rises relative to the bottom one because the greater expansion of the zinc rods pushes the middle bridge, and therefore the bob, upwards to match the
An ignition system is a system for igniting a fuel-air mixture. Ignition systems are well known in the field of internal combustion engines such as those used in petrol (gasoline) engines used to power the majority of motor vehicles, but they are also used in many other applications such as in oil-fired and gas-fired boilers, rocket engines, etc.
The first ignition system to use an electric spark was probably Alessandro Volta's toy electric pistol from the 1780s. Virtually all petrol engines today use an electric spark for ignition.
Diesel engines rely on fuel compression for ignition, but usually also have glowplugs that preheat the combustion chamber to allow starting of the engine in cold weather. Other engines may use a flame, or a heated tube, for ignition.
The simplest form of spark ignition is that using a magnet. The engine spins a magnet inside a coil, or, in the earlier designs, a coil inside a fixed magnet, and also operates a contact breaker, interrupting the current and causing the voltage to be increased sufficiently to jump a small gap. The spark plugs are connected directly from the magneto output. Early magnetos had one coil, with the contact breaker (sparking
An ionocraft or ion-propelled aircraft, commonly known as a lifter or hexalifter, is an electrohydrodynamic (EHD) device (utilizing an electrical phenomenon known as the Biefeld–Brown effect) to produce thrust in the air, without requiring any combustion or moving parts. The term "Ionocraft" dates back to the 1960s, an era in which EHD experiments were at their peak. In its basic form, it simply consists of two parallel conductive electrodes, one in the form of a fine wire and another which may be formed of either a wire grid, tubes or foil skirts with a smooth round surface. When such an arrangement is powered up by high voltage in the range of a few kilovolts, it produces thrust. The ionocraft forms part of the EHD thruster family, but is a special case in which the ionisation and accelerating stages are combined into a single stage.
The device is a popular science fair project for students. It is also popular among anti-gravity or so-called "electrogravitics" proponents, especially on the Internet, where it is commonly referred to as a lifter.
The term "lifter" is an accurate description because it is not an anti-gravity device, but produces lift in the same sense as a rocket
In railroading, the pilot is the device mounted at the front of a locomotive to deflect obstacles from the track that might otherwise derail the train. In some countries it is also called cowcatcher or cattle catcher.
In addition to the pilot, small metal bars called life-guards, rail guards or (UK) guard irons are provided immediately in front of the wheels. They knock away smaller obstacles lying directly on the running surface of the railhead. Historically fenced-off railway systems in Europe relied exclusively on these devices and forwent the use of pilots, but this design is rarely used in modern systems.
Trams use in place of the pilot a device called a fender. Objects lying on the tram track get hit by a sensor bracket, which triggers the lowering of a basket shaped device to the ground preventing overrunning of the obstacles by dragging it along the road surface in front of the wheels.
In snowy areas the pilot has also the function of a snowplow.
The pilot was invented by Charles Babbage in the 19th century, during his period of working for the Liverpool and Manchester Railway. However, Babbage's invention was not built, and it is uncertain whether later users were aware of
Microwave popcorn is a convenience food consisting of unpopped popcorn in an enhanced, sealed paper bag intended to be heated in a microwave oven. In addition to the dried corn the bags typically contain solidified cooking oil, one or more seasonings (often salt), and natural or artificial flavorings or both.
The bag is typically partially folded when it is placed in a microwave, and inflates as a result of steam pressure from the heated kernels.
The design of a microwave popcorn bag is specifically keyed to avoid popped kernel scorching, an undesirable effect that takes place when popped kernels are heated above 300 °F (149 °C).
A susceptor, usually a metalized film laminated onto the paper of the bag, absorbs microwaves and concentrates heat at the film interface, thus ensuring a heat distribution focused on the hard-to-heat flavor coating so that the unpopped kernels are evenly coated prior to popping, thereby ensuring even flavor throughout the product.
An early susceptor popcorn bag design was patented by the American company General Mills in 1981 (US Patent #4,267,420).
Care in package design is needed for food safety.
Another safety issue is the fact that the amount of
The thrashing machine, or, in modern spelling, threshing machine (or simply thresher), was a machine first invented by Scottish mechanical engineer Andrew Meikle for use in agriculture. It was invented (c.1784) for the separation of grain from stalks and husks. For thousands of years, grain was separated by hand with flails, and was very laborious and time consuming. Mechanization of this process took much of the drudgery out of farm labour.
The Swing Riots in the UK were partly a result of the threshing machine. Following years of war, high taxes and low wages, farm labourers finally revolted in 1830. These farm labourers had faced unemployment for a number of years due to the widespread introduction of the threshing machine and the policy of enclosing fields. No longer were thousands of men needed to tend the crops, a few would suffice. With fewer jobs, lower wages and no prospects of things improving for these workers the threshing machine was the final straw, the machine was to place them on the brink of starvation. The Swing Rioters smashed threshing machines and threatened farmers who had them.
The riots were dealt with very harshly. Nine of the rioters were hanged and a
The Trampe bicycle lift (Norwegian: Sykkelheisen Trampe) was the first, and only, bicycle lift in the world. The prototype was built in 1993 in Trondheim, and was removed in early 2012. Trampe is a Norwegian verb meaning "to stomp".
To use the Trampe, a keycard (see picture) was bought or rented. Buying and renting keycards both cost 100 kroner, but the fee was refunded when renting. The card gave unlimited numbers of use.
When using the lift, the right foot is placed on the starting point (the left foot stays on the bicycle pedal), the keycard was inserted in the card reader and one pushes the start button. After a few seconds, the user is pushed forward and a footplate emerges. A common mistake among tourists and other first-time users is that they don't keep their right leg outstretched and their body tilted forward. This made it hard to maintain balance on the footplate, and can result in falling off.
In the summer months, the Trampe was used extensively by both commuting inhabitants of Trondheim and tourists with rented keycards.
Teenagers sometimes rode (balanced on) the footplate without a bicycle, for fun.
A Wheatstone bridge is an electrical circuit used to measure an unknown electrical resistance by balancing two legs of a bridge circuit, one leg of which includes the unknown component. Its operation is similar to the original potentiometer. It was invented by Samuel Hunter Christie in 1833 and improved and popularized by Sir Charles Wheatstone in 1843. One of the Wheatstone bridge's initial uses was for the purpose of soils analysis and comparison.
In the figure, is the unknown resistance to be measured; , and are resistors of known resistance and the resistance of is adjustable. If the ratio of the two resistances in the known leg is equal to the ratio of the two in the unknown leg , then the voltage between the two midpoints (B and D) will be zero and no current will flow through the galvanometer . If the bridge is unbalanced, the direction of the current indicates whether is too high or too low. is varied until there is no current through the galvanometer, which then reads zero.
Detecting zero current with a galvanometer can be done to extremely high accuracy. Therefore, if , and are known to high precision, then can be measured to high precision. Very small changes
IMAX is a motion picture film format and a set of cinema projection standards created by the Canadian company IMAX Corporation. IMAX has the capacity to record and display images of far greater size and resolution than conventional film systems. Since 2002, some feature films have been converted (or upgraded) into IMAX format for display in IMAX theatres and some have also been partially shot in IMAX.
IMAX is the most widely used system for special-venue film presentations. As of March 2012, there are 643 IMAX theatres in 52 countries.
The desire to increase the visual impact of film has a long history. In 1929, Fox introduced Fox Grandeur, the first 70 mm film format, but it quickly fell from use. In the 1950s CinemaScope (1953) and VistaVision (1954) widened the image from 35 mm film, following multi-projector systems such as Cinerama (1952). While impressive, Cinerama was difficult to install, and the seams between adjacent projected images were difficult to hide.
The IMAX system was developed by Graeme Ferguson, Roman Kroitor, Robert Kerr, and William C. Shaw.
During Expo 67 in Montreal, Kroitor's In the Labyrinth and Ferguson's Man and the Polar Regions both used
Meccano is a model construction system comprising re-usable metal strips, plates, angle girders, wheels, axles and gears, with nuts and bolts to connect the pieces. It enables the building of working models and mechanical devices.
Meccano was invented in 1901 in England by Frank Hornby and manufactured by the British company, Meccano Ltd, between 1908 and 1980. It is now manufactured in France and China. Currently sold "Erector Sets" are actually Meccano sets manufactured by Meccano S.N. of France, part of the Nikko Group of Japan.
In 1901 Frank Hornby, a clerk from Liverpool, England, invented and patented a new toy called "Mechanics Made Easy" that was based on the principles of mechanical engineering. It was a model construction kit consisting of perforated metal strips, plates and girders, with wheels, pulleys, gears, shaft collars and axles for mechanisms and motion, and nuts and bolts to connect the pieces. The perforations were at a standard ½ inch (12.7 mm) spacing, the axles were 8-gauge, and the nuts and bolts used /32 inch BSW threads. The only tools required to assemble models were a screwdriver and spanners (wrenches). It was more than just a toy: it was educational,
Propranolol (INN) is a sympatholytic non-selective beta blocker. Sympatholytics are used to treat hypertension, anxiety and panic. It was the first successful beta blocker developed. Propranolol is available in generic form as propranolol hydrochloride, as well as an AstraZeneca and Wyeth product under the brand names Inderal, Inderal LA, Avlocardyl, Deralin, Dociton, Inderalici, InnoPran XL, Sumial, Anaprilinum, Bedranol SR (Sandoz).
Propranolol is indicated for the management of various conditions including:
While once first-line treatment for hypertension, the role for beta-blockers was downgraded in June 2006 in the United Kingdom to fourth-line as they perform less well than other drugs, particularly in the elderly, and evidence is increasing that the most frequently used beta-blockers at usual doses carry an unacceptable risk of provoking type 2 diabetes.
Propranolol is also used to lower portal vein pressure in portal hypertension and prevent esophageal variceal bleeding.
Propranolol is often used by musicians and other performers to prevent stage fright. It has been taken by surgeons to reduce their own innate hand tremors during surgery.
Propranolol 80 mg daily can be used
A backhoe loader, also called a loader backhoe, digger, or colloquially shortened to backhoe, is a heavy equipment vehicle that consists of a tractor fitted with a shovel/bucket on the front and a small backhoe on the back. Due to its (relatively) small size and versatility, backhoe loaders are very common in urban engineering and small construction projects (such as building a small house, fixing urban roads, etc.). This type of machine is also known as a TLB (Tractor-Loader-Backhoe).
The backhoe loader was invented in the UK in 1953 by Joseph Cyril Bamford, founder of J. C. Bamford (JCB), by equipping a farm tractor with both a backhoe and a front-mounted loading bucket. Although based on a tractor, a backhoe loader is almost never called a tractor when both the loader and the backhoe are permanently attached. Backhoe loaders are also not generally used for towing and usually do not have a power take-off (PTO). When the backhoe is permanently attached, the machine usually has a seat that can swivel to the rear to face the hoe controls. Removable backhoe attachments almost always have a separate seat on the attachment itself.
In Britain and Ireland they are commonly referred to
Basketball is a team sport, the objective being to shoot a ball through a basket horizontally positioned to score points while following a set of rules. Usually, two teams of five players play on a marked rectangular court with a basket at each width end. Basketball is one of the world's most popular and widely viewed sports.
A regulation basketball hoop consists of a rim 18 inches in diameter and 10 feet high mounted to a backboard. A team can score a field goal by shooting the ball through the basket during regular play. A field goal scores two points for the shooting team if a player is touching or closer to the basket than the three-point line, and three points (known commonly as a 3 pointer or three) if the player is behind the three-point line. The team with the most points at the end of the game wins, but additional time (overtime) may be issued when the game ends with a draw. The ball can be advanced on the court by bouncing it while walking or running (dribbling) or throwing (passing) it to a team mate. It is a violation to move without dribbling the ball (travelling), to carry it, or to hold the ball with both hands then resume dribbling (double dribble).
The elephant clock was a medieval Islamic invention by the Kurdish engineer al-Jazari (1136–1206), consisting of a weight powered water clock in the form of an elephant. The various elements of the clock are in the housing on top of the elephant. They were designed to move and make a sound each half hour.
A modern full-size working reproduction can be found as a centrepiece in the Ibn Battuta Mall, a shopping mall in Dubai, United Arab Emirates. Another working reproduction can be seen outside the Musée d'Horlogerie du Locle, Château des Monts, in Le Locle, Switzerland.
In addition to its mechanical innovations, the clock itself is seen as an early example of multiculturalism represented in technology. The elephant represents the Indian and African cultures, the dragon represents Chinese culture, the phoenix represents ancient Egyptian culture, the water work represents ancient Greek culture, and the turban represents Islamic culture.
The timing mechanism is based on a water-filled bucket hidden inside the elephant(underneath the head). In the bucket is a deep bowl floating in the water, but with a small hole in the centre. The bowl takes half an hour to fill through this hole. In
A fire extinguisher, flame extinguisher, or simply an extinguisher, is an active fire protection device used to extinguish or control small fires, often in emergency situations. It is not intended for use on an out-of-control fire, such as one which has reached the ceiling, endangers the user (i.e., no escape route, smoke, explosion hazard, etc.), or otherwise requires the expertise of a fire department. Typically, a fire extinguisher consists of a hand-held cylindrical pressure vessel containing an agent which can be discharged to extinguish a fire.
In the United States, fire extinguishers, in all buildings other than houses, are generally required to be serviced and inspected by a Fire Protection service company at least annually. Some jurisdictions require more frequent service for fire extinguishers. The servicer places a tag on the extinguisher to indicate the type of service performed (annual inspection, recharge, new fire extinguisher) and when.
There are two main types of fire extinguishers: stored pressure and cartridge-operated. In stored pressure units, the expellant is stored in the same chamber as the firefighting agent itself. Depending on the agent used, different
The Mecanum wheel is one design for a wheel which can move in any direction. It is sometimes called the Ilon wheel after its Swedish inventor, Bengt Ilon, who came up with the idea in 1973 when he was an engineer with the Swedish company Mecanum AB.
It is a conventional wheel with a series of rollers attached to its circumference. These rollers have an axis of rotation at 45° to the plane of the wheel in a plane parallel to the axis of rotation of the wheel. A typical configuration is the four-wheeled one of the URANUS omni-directional mobile robot (pictured) or a wheel chair with Mecanum wheels (similar to that pictured). By alternating wheels with left and right-handed rollers, so that each wheel applies force roughly at right angles to the diagonal the wheel is on, the vehicle is stable and can be made to move in any direction and turn by varying the speed and direction of rotation of each wheel. Moving all four wheels in the same direction causes forward or backward movement, running the wheels on one side in the opposite direction to those on the other side causes rotation of the vehicle, and running the wheels on one diagonal in the opposite direction to those on the other
A Splayd (plural 'Splayds') is a brand of sporf, an eating utensil combining the functions of spoon, fork, and knife. It was created by William McArthur in the 1940s in Sydney, Australia.
In addition to an overall spoon shape with four fork tines, it has two hard, flat edges on either side, suitable for cutting through soft food.
The UK Licensee for manufacturing and distribution of "Splayds" was held by Viners of Sheffield during the 1970s. At that time they were one of the biggest cutlery manufacturers in Great Britain.
The Splayd is exclusively distributed worldwide by Cambur Industries Pty Ltd (Australia).
Splayd may seem to be an unusually-spelled portmanteau of "spoon" and "blade", but according to the Splayd website, the name is "after the verb to splay - to slant, slope or spread outwards".
The ANITA Mark VII and ANITA Mark VIII calculators were launched simultaneously in late 1961 as the world's first all-electronic desktop calculators. Designed and built by the Bell Punch Co. in Britain, and marketed through its Sumlock Comptometer division, they used vacuum tubes and cold-cathode switching tubes in their logic circuits and nixie tubes for their numerical displays.
They were the first of a series of desktop and hand-held electronic calculators that the company was to develop and sell under the ANITA name into the mid-1970s.
The acronym 'ANITA' was officially proclaimed to be derived from, variously, A New Inspiration To Arithmetic, or A New Inspiration To Accounting, though there have been rumours that this was also the name of the designer's wife.
The Bell Punch Company (named after its first product, a ticket punch with a bell used by tram and bus conductors) had been producing a very successful range of key-driven mechanical calculators of the Comptometer type under the names "Plus" and "Sumlock", since the 1930s. In 1956 the young graduate Norbert Kitz (also known as Norman Kitz), who had worked on the early British Pilot ACE computer project, had a chance
The Congreve Rocket was a British military weapon designed and developed by Sir William Congreve in 1804.
The rocket was developed by the Royal Arsenal following the experiences of the Second, Third and Fourth Mysore Wars. The wars fought between the British East India Company and the kingdom of Mysore in India made use of rockets as a weapon. After the wars, several Mysore rockets were sent to England, and from 1801, William Congreve set on a research and development programme at the Arsenal's laboratory. The Royal Arsenal's first demonstration of solid fuel rockets was in 1805. The rockets were used effectively during the Napoleonic Wars and the War of 1812.
A military tactic developed by Tipu Sultan and his father, Hyder Ali, was the use of mass attacks with rocket artillery brigades on infantry formations. Tipu Sultan wrote a military manual called Fathul Mujahidin in which 200 rocket men were prescribed to each Mysorean rocket artillery brigade known as Cushoon. Mysore had 16 to 24 cushoons of infantry. The areas of town where rockets and fireworks were manufactured were known as Taramandal Pet ("Galaxy Market").
The rocket men were trained to launch their rockets at an angle
Crokinole ( /ˈkroʊkɨnoʊl/ KROH-ki-nohl) is an action board game similar in various ways to pitchnut, carrom, marbles, and shove ha'penny, with elements of shuffleboard and curling reduced to table-top size. Players take turns shooting discs across the circular playing surface, trying to have their discs land in the higher-scoring regions of the board, while also attempting to knock away opposing discs.
Board dimensions vary with a playing surface typically of polished wood or laminate approximately 27 inches (690 mm) in diameter. The arrangement is 3 concentric rings worth 5, 10, and 15 points as you move in from the outside. There is a shallow 20-point hole at the center. The inner 15-point ring is guarded with 8 small bumpers or posts. The outer ring of the board is divided into four quadrants. The outer edge of the board is raised a bit to keep errant shots from flying out, with a gutter between the playing surface and the edge to collect discarded pieces. Crokinole boards are typically octagonal or round in shape. The discs are roughly checker-sized, slightly smaller in diameter than the board's central hole, and often have concave faces to reduce sliding friction.
Resurgam (latin: "I shall rise again") is the name given to two early Victorian submarines designed and built in Britain by Reverend George Garrett as a weapon to penetrate the chain netting placed around ship hulls to defend against attack by torpedo vessels.
The first Resurgam, built in 1878, was a 14 ft (5 m), hand powered, one-man vessel nicknamed "the curate's egg" due to its shape. Its small size and one-man crew meant it would have been ineffective as a weapon.
The second Resurgam was built by Cohran & Co. at Birkenhead, England, and launched on 26 November 1879. Her construction was of iron plates fastened to iron frames, with the central section of the vessel clad with wood secured by iron straps and as built, she was 45 feet (14 m) long by 10 feet (3.0 m) in diameter, weighed 30 long tons (30 t), and had a crew of 3. She was powered by a closed cycle steam engine originally patented in 1872 by the American engineer Eugene Lamm which provided enough steam to turn the single propeller for up to 4 hours. She was designed to have positive buoyancy, and diving was controlled by a pair of hydroplanes amidships. At the time she cost £1,538.
After successful trials in the East
A tin can, tin (especially in British English and Canadian English ), steel can, or a can, is a sealed container for the distribution or storage of goods, composed of thin metal. Many cans require opening by cutting the "end" open; others have removable covers. Cans hold diverse contents: foods, beverages, oil, chemicals, etc.
"Tin" cans are made of tinplate (tin-coated steel). In some locations, cans made of aluminium are called "tin cans".
The tin can was patented in 1810 by British merchant Peter Durand, based on experimental food preservation work in glass containers by the French inventor Nicholas Appert the year before. Durand did not pursue food canning himself, but, in 1812, sold his patent to two Englishmen, Bryan Donkin and John Hall, who set up a commercial canning factory, and by 1813 were producing their first canned goods for the British Army.
Early cans were sealed with lead soldering, which led to lead poisoning. Famously, in the 1845 Arctic expedition of Sir John Franklin, crew members suffered from severe lead poisoning after three years of eating canned dog.
In 1901, the American Can Company was founded which, at the time, produced 90% of United States tin cans.
A difference engine is an automatic mechanical calculator designed to tabulate polynomial functions. The name derives from the method of divided differences, a way to interpolate or tabulate functions by using a small set of polynomial coefficients. Both logarithmic and trigonometric functions, functions commonly used by both navigators and scientists, can be approximated by polynomials, so a difference engine can compute many useful sets of numbers.
The historical difficulty in producing error free tables by teams of mathematicians and human "computers" spurred Charles Babbage's desire to build a mechanism to automate the process.
J. H. Müller, an engineer in the Hessian army, conceived of the idea of a difference machine. This was described in a book published in 1786, but Müller failed to obtain funding to progress with the idea.
In 1822, Charles Babbage proposed the use of such a machine in a paper to the Royal Astronomical Society on 14 June entitled "Note on the application of machinery to the computation of astronomical and mathematical tables". This machine used the decimal number system and was powered by cranking a handle. The British government was interested, since
A g-suit, or the more accurately named anti-g suit, is a flight suit worn by aviators and astronauts who are subject to high levels of acceleration force (g). It is designed to prevent a black-out and g-LOC (g-induced Loss Of Consciousness) caused by the blood pooling in the lower part of the body when under acceleration, thus depriving the brain of blood. Black-out and g-LOC has caused a number of fatal aircraft accidents.
If blood is allowed to pool in the lower areas of the body, the brain will be deprived of blood, leading to temporary hypoxia. Hypoxia first causes a greyout (a dimming of the vision), also called brownout, followed by tunnel vision and ultimately complete loss of vision 'blackout' followed by g-induced Loss Of Consciousness or 'g-LOC'. The danger of g-LOC to aircraft pilots is magnified because on relaxation of g there is a period of disorientation before full sensation is re-gained. A g-suit does not so much increase the g-threshold, but makes it possible to sustain high g longer without excessive physical fatigue. The resting g-tolerance of a typical person is anywhere from 3-5 g depending on the person. A g-suit will typically add 1 g of tolerance to that
The kelvin is a unit of measurement for temperature. It is one of the seven base units in the International System of Units (SI) and is assigned the unit symbol K. The Kelvin scale is an absolute, thermodynamic temperature scale using as its null point absolute zero, the temperature at which all thermal motion ceases in the classical description of thermodynamics. The kelvin is defined as the fraction ⁄273.16 of the thermodynamic temperature of the triple point of water (exactly 0.01 °C or 32.018 °F).
The Kelvin scale is named after the Belfast-born, Glasgow University engineer and physicist William Thomson, 1st Baron Kelvin (1824–1907), who wrote of the need for an "absolute thermometric scale". Unlike the degree Fahrenheit and degree Celsius, the kelvin is not referred to or typeset as a degree. The kelvin is the primary unit of measurement in the physical sciences, but is often used in conjunction with the degree Celsius, which has the same magnitude. Subtracting 273.16 K from the temperature of the triple point of water (0.01 °C) makes absolute zero (0 K) equivalent to −273.15 °C (−460 °F).
When reference is made to the unit kelvin (either a specific temperature or a
A monoplane is a fixed-wing aircraft with one main set of wing surfaces, in contrast to a biplane or triplane. Since the late 1930s it has been the most common form for a fixed wing aircraft.
The main distinction between types of monoplane is where the wings attach to the fuselage:
Some of the first attempts of heavier-than-air flying machines were monoplanes; the Monoplane built in 1874 by Felix du Temple de la Croix is one example. Other early attempts of flight by a monoplane were carried out in 1884 by Alexander Mozhaysky. According to the Encyclopædia Britannica, the first successful monoplane flight was on 18 March 1906, covering just 12 m (40 feet) at Montesson, France in a craft fashioned by Traian Vuia, a Romanian inventor.
The first successful aircraft were biplanes, but many pioneering aircraft were monoplanes, for instance the Blériot XI that flew across the English Channel in 1909. Throughout 1909-1910 Hubert Latham set multiple altitude records in his Antoinette IV monoplane, eventually reaching 1,384 m (4,541 ft). The Fokker Eindecker of 1915 was a successful fighter aircraft. The first all metal aircraft was a monoplane, the German Junkers J 1 which first flew in
Electricity distribution is the final stage in the delivery of electricity to end users. A distribution system's network carries electricity from the transmission system and delivers it to consumers. Typically, the network would include medium-voltage (less than 50 kV) power lines, substations and pole-mounted transformers, low-voltage (less than 1 kV) distribution wiring and sometimes meters.
In the early days of electricity distribution, direct current (DC) generators were connected to loads at the same voltage. The generation, transmission and loads had to be of the same voltage because there was no way of changing DC voltage levels, other than inefficient motor-generator sets. Low DC voltages were used (on the order of 100 volts) since that was a practical voltage for incandescent lamps, which were the primary electrical load. Low voltage also required less insulation for safe distribution within buildings.
The losses in a cable are proportional to the square of the current, the length of the cable, and the resistivity of the material, and are inversely proportional to cross-sectional area. Early transmission networks used copper cable, which is one of the best economically
A rotary tiller, also known as a rototiller, rotavator, rotary hoe, power tiller, or rotary plough (in US: plow), is a motorised cultivator that works the soil by means of rotating tines or blades. Rotary tillers are either self-propelled or drawn as an attachment behind either a two-wheel tractor or four-wheel tractor. For two-wheel tractors they are rigidly fixed and powered via couplings to the tractors' transmission. For four-wheel tractors they are attached by means of a three-point hitch and driven by a power take-off (PTO).
In some parts of the world, the term "power tiller" can encompass the larger and similar appearing two-wheeled tractor, a machine which does, however, operate different attachments; in most English-speaking regions this difference is considered more rigid, as the term power tiller (and this article) refers solely to devices with soil cultivation as their primary and often only function.
The powered rotary hoe was invented by Arthur Clifford Howard who, in 1912, began experimenting with rotary tillage on his father's farm at Gilgandra, New South Wales, Australia. Initially using his father's steam tractor engine as a power source, he found that ground
Shrapnel shells were anti-personnel artillery munitions which carried a large number of individual bullets close to the target and then ejected them to allow them to continue along the shell's trajectory and strike the target individually. They relied almost entirely on the shell's velocity for their lethality. The munition has been obsolete since the end of World War I for anti-personnel use, when it was superseded by high-explosive shells for that role. The functioning and principles behind Shrapnel shells are fundamentally different from high-explosive shell fragmentation. Shrapnel is named after Major-General Henry Shrapnel (1761–1842), an English artillery officer, whose experiments, initially conducted in his own time and at his own expense, culminated in the design and development of a new type of artillery shell.
In 1784, Lieutenant Shrapnel of the Royal Artillery began developing an anti-personnel weapon. At the time artillery could use "canister shot" to defend themselves from infantry or cavalry attack, which involved loading a tin or canvas container filled with small iron or lead balls instead of the usual cannonball. When fired, the container burst open during passage
A tank is a tracked, armoured fighting vehicle designed for front-line combat which combines operational mobility and tactical offensive and defensive capabilities. Firepower is normally provided by a large-calibre main gun in a rotating turret and secondary machine guns, while heavy armour and all-terrain mobility provide protection for the tank and its crew, allowing it to perform all primary tasks of the armoured troops on the battlefield.
Tanks in World War I were developed separately and simultaneously by Great Britain and France as a means to break the deadlock of trench warfare on the Western Front. Their first use in combat was by the British Army on September 15, 1916 at Flers-Courcelette, during the Battle of the Somme. The name "tank" was adopted by the British during the early stages of their development, as a security measure to conceal their purpose (see Etymology). While the French and British built thousands of tanks between them, Germany developed and brought into service only a single design the A7V producing 20 vehicles due to lack of capacities or resources.
Tanks of the interwar period evolved into the designs of World War II. Important concepts of armoured
The Bubble Project, as proclaimed by its manifesto, aims to counteract corporate marketing and advertisement messages in public spaces.
The project was conceived by Ji Lee, an artist and art director who originally printed 15,000 stickers that look like speech bubbles used in comic strips. He posts these blank speech bubbles on top of advertisements throughout New York City allowing anyone who sees them to write in their comments and thoughts. By filling in the bubbles people engage in the project and transform “the corporate monologue into an open dialogue”. After time passes, the comments are photographed and posted on the project’s website.
The Bubble Project has quickly gained popularity and independent efforts have sprung up in other parts of the world in countries such as Italy or Argentina.
On June 1, 2006, a book written by Lee himself was released. It explains the whole idea behind the project and shows the best pictures taken in the first 4 years, showing the results of the project.
Another project by Ji Lee
A vacuum cleaner is a device that uses an air pump to create a partial vacuum to suck up dust and dirt, usually from floors, and optionally from other surfaces as well. The dirt is collected by either a dustbag or a cyclone for later disposal. Vacuum cleaners, which are used in homes as well as in industry, exist in a variety of sizes and models— small battery-operated hand-held devices, domestic central vacuum cleaners, huge stationary industrial appliances that can handle several hundred litres of dust before being emptied, and self-propelled vacuum trucks for recovery of large spills or removal of contaminated soil.
The vacuum cleaner evolved from the carpet sweeper via manual vacuum cleaners. The first manual models, using bellows, came in the 1860s, and the first motorized models came in the beginning of the 20th century.
Daniel Hess of West Union, Iowa, invented a vacuum cleaner in 1860, calling it a carpet sweeper instead of a vacuum cleaner. His machine did, in fact, have a rotating brush like a traditional carpet sweeper, and also possessed an elaborate bellows mechanism on top of the body to generate suction of dust and dirt. Hess received a patent (US No. 29.077) for his
The Davy lamp is a safety lamp for use in flammable atmospheres, consisting of a wick lamp with the flame enclosed inside a mesh screen. It was invented in 1815 by Sir Humphry Davy. It originally burned a heavy vegetable oil. It was created for use in coal mines, to reduce the danger of explosions due to the presence of methane and other flammable gases, called firedamp or minedamp.
Sir Humphry Davy had discovered that a flame enclosed inside a mesh of a certain fineness cannot ignite firedamp. The screen acts as a flame arrestor; air (and any firedamp present) can pass through the mesh freely enough to support combustion, but the holes are too fine to allow a flame to propagate through them and ignite any firedamp outside the mesh.
The news about Davy's lamp was made public at a Royal Society meeting in Newcastle on 3 November 1815, and the paper describing the lamp was formally presented on 9 November. For it, Davy was awarded the Society's Rumford Medal. (Davy's invention had been preceded by that of William Reid Clanny, an Irish doctor at Bishopwearmouth, who had also read a paper to the Royal Society in May 1813. Reid Clanny's lamp was successfully tested at Harrington Mill
A rubber band (in some regions known as a binder, an elastic or elastic band, a lackey band, laggy band, lacka band or gumband) is a short length of rubber and latex formed in the shape of a loop and is commonly used to hold multiple objects together. The rubber band was patented in England on March 17, 1845 by Stephen Perry.
Rubber bands are made by extruding the rubber into a long tube to provide its general shape, putting the tubes on mandrels and curing the rubber with heat, and then slicing it across the width of the tube into little bands.
While other rubber products may use synthetic rubber, most rubber bands are primarily manufactured using natural rubber because of its superior elasticity.
Natural rubber originates from the sap of the rubber tree. Natural rubber is made from latex which is acquired by tapping into the bark layers of the rubber tree. Rubber trees belong to the spurge family (Euphorbiaceae) and live in warm, tropical areas. Once the latex has been “tapped” and is exposed to the air it begins to harden and become elastic, or “rubbery.” Rubber trees only survive in hot, humid climates near the equator and so the majority of latex is produced in the Southeast
Bifocals are eyeglasses with two distinct optical powers. Bifocals are most commonly prescribed to people with presbyopia who also require a correction for myopia, hyperopia, and/or astigmatism.
Benjamin Franklin is generally credited with the invention of bifocals. Serious historians have, from time to time, produced evidence to suggest that others may have preceded him in the invention; however, a correspondence between George Whatley and John Fenno, editor of The Gazette of the United States, suggested that Franklin had indeed invented bifocals, and perhaps 50 years earlier than had been originally thought. Since many inventions are developed independently by more than one person, it is possible that the invention of bifocals may have been such a case. Nonetheless, Benjamin Franklin is certainly among the first to wear bifocal lenses, and Franklin's letters of correspondence suggest that he invented them independently, regardless of whether he was the first to invent them.
John Isaac Hawkins, the inventor of trifocal lenses, coined the term bifocals in 1824 and credited Dr. Franklin.
In 1955, Irving Rips of Younger Optics created the first seamless or "invisible" bifocal, a
BigBelly is a solar powered, rubbish-compacting bin, manufactured by U.S. company BigBelly Solar for use in public spaces such as parks, beaches, amusement parks, and universities. The bin was designed and originally manufactured in Needham, Massachusetts by Seahorse Power, a company set up in 2003 with the aim of reducing fossil fuel consumption. The first machine was installed in Vail, Colorado in 2004. Other locations to since use the bin include Boston, Massachusetts, Chicago, Illinois, Baltimore, Maryland, Philadelphia, Pennsylvania, Ventura, California, and Queens, New York. Due to the bin's commercial success, Seahorse Power changed its name to BigBelly Solar.
The bin has a capacity of 567 litres. Its compaction mechanism exerts 5.3kN of force, increasing the bin's effective capacity by five. The compaction mechanism is chain-driven, using no hydraulic fluids. Maintenance consists of lubricating the front door lock annually. The mechanism runs on a standard 12 volt battery, which is kept charged by the solar panel. The battery reserve lasts for approximately three weeks. Wireless technology-enabled units report their status into the CLEAN (Collection, Logistics, Efficiency
A cochlear implant (CI) is a surgically implanted electronic device that provides a sense of sound to a person who is profoundly deaf or severely hard of hearing. Cochlear implants are often referred to as a bionic ear.
Cochlear implants may help provide hearing in patients that are deaf due to damage to sensory hair cells in their cochlea. In those patients, they can often enable sufficient hearing to allow better understanding of speech. The quality of sound is different from natural hearing, with less sound information being received and processed by the brain. However, many patients are able to hear and understand speech and environmental sounds. Newer devices and processing strategies allow recipients to hear better in noise, enjoy music, and even use their implant processors while swimming.
As of December 2010, approximately 219,000 people worldwide have received cochlear implants; in the U.S., roughly 42,600 adults and 28,400 children are recipients. The vast majority are in developed countries due to the high cost of the device, surgery and post-implantation therapy. A small but growing segment of recipients have bilateral implants (one implant in each cochlea).
An electric motor is an electromechanical device that converts electrical energy into mechanical energy.
Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force. The reverse process, producing electrical energy from mechanical energy, is done by generators such as an alternator or a dynamo; some electric motors can also be used as generators, for example, a traction motor on a vehicle may perform both tasks. Electric motors and generators are commonly referred to as electric machines.
Electric motors are found in applications as diverse as industrial fans, blowers and pumps, machine tools, household appliances, power tools, and disk drives. They may be powered by direct current, e.g., a battery powered portable device or motor vehicle, or by alternating current from a central electrical distribution grid or inverter. The smallest motors may be found in electric wristwatches. Medium-size motors of highly standardized dimensions and characteristics provide convenient mechanical power for industrial uses. The very largest electric motors are used for propulsion of ships, pipeline compressors, and water pumps with
An Integraph is an instrument used in mathematics for plotting the integral of a graphically defined function.
It was invented independently about 1880 by the British physicist Sir Charles Vernon Boys and by Bruno Abakanowicz, a Polish-Lithuanian mathematician from the Russian Empire.
An integraph consists of a rectangular carriage which moves left to right on rollers, two sides of which run parallel to the x axis on the Cartesian plane. The other two sides are parallel to the y axis. Along the trailing vertical (y axis) rail, slides a smaller carriage holding a tracing point. Along the leading vertical rail slides a second smaller carriage to which is affixed a small, sharp disc, which rests and rolls (but does not slide) on the graphing paper. It will not rotate about its point of contact with the paper. The trailing carriage is connected both with a point in the center of the carriage and the disc on the leading rail by a system of sliding crossheads and wires, such that the tracing point must follow the disc's tangential path.
A kaleidoscope is a cylinder with mirrors containing loose, colored objects such as beads or pebbles and bits of glass. As the viewer looks into one end, light entering the other creates a colorful pattern, due to the reflection off of the mirrors. Coined in 1817 by Scottish inventor Sir David Brewster, "kaleidoscope" is derived from the Ancient Greek καλός (kalos), "beautiful, beauty", εἶδος (eidos), "that which is seen: form, shape" and σκοπέω (skopeō), "to look to, to examine", hence "observer of beautiful forms."
A Kaleidoscope operates on the principle of multiple reflection, where several mirrors are together. Typically there are three rectangular lengthwise mirrors. Setting the mirrors at a 60-degree so that it forms a triangle. 60 degree angle apart from each other creates eight duplicate images of the objects, six at 60°, and 2 at 90°. As the tube is rotated, the tumbling of the coloured objects presents varying colours and patterns. Arbitrary patterns shows up as a beautiful symmetrical pattern created by the anreflections. A two-mirror kaleidoscope yields a pattern or patterns isolated against a solid black background, while the three-mirror (closed triangle) type
OnSpot - Automatic Tire Chains (Swedish: OnSpot - det automatiska slirskyddet), originally called InstaChain, is a snow chain mechanism for applying and dismounting snow chains to and from the wheels of a vehicle. The automatic tire chain system was created in 1977 by the Swedish inventor Göran Torneback, who mounted it onto a local milk delivery truck. The system consists of two chain wheels operated by the driver. When the chain wheels are connected to the tire sidewalls, the chains are thrown, by rotation, under the tires so that at least one chain is always between the tire and the road surface. The system is designed to work on ice, packed snow, and up to 6 inches of snow, and is a refined application of a 1915 patent granted to the American inventor W.H. Putnam.
The automatic tire chain system is permanently mounted on both sides of vehicle driving axle. The mechanism includes a chain assembly mounted with a plurality of chains rotated by a chain assembly driving unit mounted to an axle of a vehicle via a bracket. Also included is a control unit for controlling the chain assembly driving unit, thereby allowing the chains to be positioned between the wheels and road surface
A zipper, zip, or zip fastener, is a commonly used device for binding the edges of an opening of fabric or other flexible material, as on a garment or a bag. It is used in clothing (e.g., jackets and jeans), luggage and other bags, sporting goods, camping gear (e.g. tents and sleeping bags), and other items. It was invented by Gideon Sundbäck circa 1917 based on prior less effective fasteners, but many others have made improvements and different versions of the device.
The bulk of a zipper consists of two rows of protruding teeth which may be made to interdigitate, linking the rows, carrying from tens to hundreds of specially shaped metal or plastic teeth. These teeth can be either individual or shaped from a continuous coil, and are also referred to as elements. The slider, operated by hand, moves along the rows of teeth. Inside the slider is a Y-shaped channel that meshes together or separates the opposing rows of teeth, depending on the direction of the slider's movement. The word Zipper is onomatopoetic, because it was named for the sound the device makes when used, a high-pitched zip.
In many jackets and similar garments, the opening is closed entirely when the slider is at
A beer engine is a device for pumping beer, originally manually operated and typically used to dispense beer from a cask or container in a pub's basement or cellar. It was invented by John Lofting, a Dutch inventor, merchant, and manufacturer who moved from Amsterdam to London in or about 1688. He became a citizen and patented a number of inventions including his "Sucking Worm Engine", a fire hose and engine for extinguishing fires, and also a thimble knurling machine which revolutionized thimble making. He also invented a device for pumping beer. The London Gazette of 17 March 1691 stated "the patentee hath also projected a very useful engine for starting of beers and other liquors which will deliver from 20 to 30 barrels an hour which are completely fixed with brass joints and screws at reasonable rates."
The locksmith and hydraulic engineer Joseph Bramah developed beer pumping further in 1797.
Strictly the term "beer engine" refers to the pump itself, which is normally manually operated, though electrically powered and gas powered pumps are occasionally used; when manually powered, the term handpump is often used to refer to both the pump and the associated handle.
Cobalt blue is the cool blue color of the pigments made using cobalt salts of alumina. Cobalt blue pigments are extremely stable, and have historically been used as colouring agents in ceramics, (especially Chinese porcelain), jewellery, and paint. Transparent glasses are tinted with the silica-based cobalt pigment smalt.
Chemically, cobalt blue pigment is a cobalt(II) oxide-aluminium oxide, or cobalt(II) aluminate, CoAl2O4. The compound is made by sintering finely ground CoO and Al2O3 (alumina) at 1200°C. Cobalt blue is lighter and less intense than (iron-cyanide based) Prussian blue.
Cobalt blue in impure forms had long been used in Chinese porcelain, but was independently discovered as a pure alumina-based pigment by Louis Jacques Thénard in 1802. Commercial production began in France in 1807. The first recorded use of cobalt blue as a color name in English was in 1777. The leading world manufacturer of cobalt blue in the 19th century was Benjamin Wegner's Norwegian company Blaafarveværket, ("blue colour works" in Dano-Norwegian). Germany was also famous for production, especially the blue colour works (Blaufarbenwerke) in the Ore Mountains of
The grasshopper escapement is an unusual, low-friction escapement for pendulum clocks invented by British clockmaker John Harrison around 1722. An escapement, part of every mechanical clock, is the mechanism that causes the clock's gears to move forward by a fixed distance at regular intervals and also gives the pendulum (or the balance wheel) periodic pushes to keep it swinging. The grasshopper escapement was used in a few regulator clocks built during Harrison's time, and a few others over the years, but has never seen wide use. The term "grasshopper" in this connection, apparently from the kicking action of the pallets, first appears in The Horological Journal in the late 19th century.
The grasshopper escapement was invented by John Harrison who used it in his regulator clocks, and also in the first three of his marine timekeepers, H1 - H3. Determining longitudinal position was a major problem in marine navigation; Newton argued that astronomical positioning could be used, but an easier theoretical possibility was to use accurate knowledge of the time at a specific, base, location. The difference in time between local time, which was easy to measure, and the time at base gives
The Intra-aortic balloon pump (IABP) is a mechanical device that increases myocardial oxygen perfusion while at the same time increasing cardiac output. Increasing cardiac output increases coronary blood flow and therefore myocardial oxygen delivery. It consists of a cylindrical polyethylene balloon that sits in the aorta, approximately 2 centimeters (0.79 in) from the left subclavian artery and counterpulsates. That is, it actively deflates in systole, increasing forward blood flow by reducing afterload. It actively inflates in diastole, increasing blood flow to the coronary arteries. These actions combine to decrease myocardial oxygen demand and increase myocardial oxygen supply.
A computer-controlled mechanism inflates the balloon with helium from a cylinder during diastole, usually linked to either an electrocardiogram (ECG) or a pressure transducer at the distal tip of the catheter; some IABPs, such as the Datascope System 98XT, allow asynchronous counterpulsation at a set rate, though this setting is rarely used. Helium is used because its low viscosity allows it to travel quickly through the long connecting tubes, and has a lower risk than air of causing an embolism should
A safety razor is a shaving implement with a protective device positioned between the edge of the blade and the skin. The term was first used in a patent issued in 1880, for a razor in the basic contemporary configuration with a handle attached at right angles to a head in which a removable blade is placed (although this form predated the patent). Its edge was protected by a comb patterned on various types of protective guards that had been affixed to open-blade straight razors during the preceding decades. Some safety razors in present-day production retain a comb but the more common protective device is now a solid safety bar. The initial purpose of these protective devices was to reduce the level of skill needed for injury-free shaving, thereby reducing the reliance on professional barbers for providing that service and raising personal grooming standards. Prior to the introduction of the disposable razor blade by King Camp Gillette in 1901, however, safety razor users still needed to strop and hone the edges of their blades. These are not trivial skills (honing frequently being left to a professional) and remained a barrier to the ubiquitous adopting of the be your own barber
Colossus was the world's first electronic, digital, computer that was at all programmable. The Colossus computers were used by British codebreakers to help read encrypted high-level German Army messages during World War II. They used thermionic valves (vacuum tubes) to perform the calculations.
Colossus was designed by engineer Tommy Flowers with input from Sidney Broadhurst, William Chandler, Allen Coombs and Harry Fensom, at the Post Office Research Station, located at Dollis Hill, to solve a problem posed by mathematician Max Newman at the Government Code and Cypher School (GC&CS) at Bletchley Park. The prototype, Colossus Mark 1, was shown to be working in December 1943 and was operational at Bletchley Park by 5 February 1944. An improved Colossus Mark 2 first worked on 1 June 1944, just in time for the Normandy Landings. Ten Colossus computers were in use by the end of the war.
The Colossus computers were used to help decipher teleprinter messages which had been encrypted using the Lorenz SZ40/42 machine. British codebreakers referred to encrypted German teleprinter traffic as "Fish" and called the SZ40/42 machine and the intercepted messages "Tunny". Colossus was used for
In computing, a mouse is a pointing device that functions by detecting two-dimensional motion relative to its supporting surface. Physically, a mouse consists of an object held under one of the user's hands, with one or more buttons.
The mouse sometimes features other elements, such as "wheels", which allow the user to perform various system-dependent operations, or extra buttons or features that can add more control or dimensional input. The mouse's motion typically translates into the motion of a pointer on a display, which allows for fine control of a graphical user interface.
The earliest known publication of the term mouse as a computer pointing device is in Bill English's 1965 publication "Computer-Aided Display Control".
The online Oxford Dictionaries entry for mouse states the plural for the small rodent is mice, while the plural for the small computer connected device is either mice or mouses. However, in the use section of the entry it states that the more common plural is mice, and that the first recorded use of the term in the plural is mice as well (though it cites a 1984 use of mice when there were actually several earlier ones). The term mice was seen in print in
An overhead valve (OHV) engine, also informally called pushrod engine or I-head engine, is a type of piston engine that places the camshaft within the cylinder block (usually beside and slightly above the crankshaft in a straight engine or directly above the crankshaft in the V of a V engine), and uses pushrods or rods to actuate rocker arms above the cylinder head to actuate the valves. Lifters or tappets are located in the engine block between the camshaft and pushrods. The more modern overhead camshaft (OHC) design (still literally overhead valve) avoids the use of pushrods by putting the camshaft in the cylinder head.
In 1949, Oldsmobile introduced the Rocket V8. It was the first high-compression I-head design, and is the archetype for most modern pushrod engines. General Motors is the world's largest pushrod engine producer, producing both V6 and V8 pushrod engines.
Few pushrod type engines remain in production outside of the United States market. This is in part a result of some countries passing laws to tax engines based on displacement, because displacement is somewhat related to the emissions and fuel efficiency of an automobile. This has given OHC engines a regulatory
Prestressed concrete is a method for overcoming concrete's natural weakness in tension. It can be used to produce beams, floors or bridges with a longer span than is practical with ordinary reinforced concrete. Prestressing tendons (generally of high tensile steel cable or rods) are used to provide a clamping load which produces a compressive stress that balances the tensile stress that the concrete compression member would otherwise experience due to a bending load. Traditional reinforced concrete is based on the use of steel reinforcement bars, rebars, inside poured concrete.
Prestressing can be accomplished in three ways: pre-tensioned concrete, and bonded or unbonded post-tensioned concrete.
Pre-tensioned concrete is cast around already tensioned tendons. This method produces a good bond between the tendon and concrete, which both protects the tendon from corrosion and allows for direct transfer of tension. The cured concrete adheres and bonds to the bars and when the tension is released it is transferred to the concrete as compression by static friction. However, it requires stout anchoring points between which the tendon is to be stretched and the tendons are usually in a
The Shuttle Remote Manipulator System (SRMS), or Canadarm (Canadarm 1), was a mechanical arm used on the Space Shuttle to maneuver a payload from the payload bay of the orbiter to its deployment position and then release it. It can also grapple a free-flying payload, maneuver it to the payload bay of the orbiter and berth it in the orbiter. It was first used on the second Space Shuttle mission STS-2, which was launched November 13, 1981. After the destruction of Space Shuttle Columbia during STS-107, NASA began to always pair the Canadarm with the Orbiter Boom Sensor System (OBSS), a boom containing instruments to inspect the exterior of the shuttle for damage to the thermal protection system.
The Canadarm is 15.2 metres (50 ft 3 in) long and 38 centimetres (15 inches) in diameter and has six degrees of freedom. It weighs 410 kg (905 pounds) by itself, and 450 kg (994 lb) as part of the total system. The Canadarm has six joints that correspond roughly to the joints of the human arm, with shoulder yaw and pitch joints; an elbow pitch joint; and wrist pitch, yaw, and roll joints. The end effector is the unit at the end of the wrist that actually grabs, or grapples, the payload. The
The Watt steam engine (alternatively known as the Boulton and Watt steam engine) was the first type of steam engine to make use of steam at a pressure just above atmospheric to drive the piston helped by a partial vacuum. Improving on the design of the 1712 Newcomen engine, the Watt steam engine, developed sporadically from 1763 to 1775, was the next great step in the development of the steam engine. Offering a dramatic increase in fuel efficiency, the new design replaced Newcomen engines in areas where coal was expensive, and then went on to be used in the place of most natural power sources such as wind and water. James Watt's design became synonymous with steam engines, due in no small part to his business partner, Matthew Boulton.
In 1698, the English mechanical designer Thomas Savery invented a steam pumping appliance that drew water directly from a well by a vacuum, then sent it up to a higher level by steam pressure. The appliance was also proposed for draining mines, but its pumping height was limited, making this impracticable. It consumed a large amount of fuel compared with later engines.
The solution to draining deep mines was found by Thomas Newcomen who developed an
The Burr Arch Truss — or simply Burr Truss or Burr Arch — is a combination of an arch and a multiple kingpost truss design. It was invented in 1804 by Theodore Burr, patented on April 3, 1817, and used in bridges, usually covered bridges.
The design principle behind the Burr arch truss is that the arch should be capable of bearing the entire load on the bridge while the truss keeps the bridge rigid. Even though the kingpost truss alone is capable of bearing a load, this was done because it is impossible to evenly balance a dynamic load crossing the bridge between the two parts. The opposite view is also held, based on computer models, that the truss performs the majority of the load bearing and the arch provides the stability. Either way, the combination of the arch and the truss provides a more stable bridge capable of supporting greater weight than either the arch or truss alone.
Indiana has a large collection of Burr Truss bridges. Of its 92 extant bridges, 53 are Burr Trusses, many of which reside in Parke County.
A Brown truss is a type of bridge truss, used in covered bridges. It is noted for its economical use of materials and is named after the inventor, Josiah Brown Jr., of Buffalo, New York, who patented it July 7, 1857 as US patent 17,722.
The Brown truss is a box truss that is a through truss (as contrasted with a deck truss) and consists of diagonal cross compression members connected to horizontal top and bottom stringers. There may be vertical or almost vertical tension members (the diagram shows these members, while the patent application diagram does not) but there are no vertical members in compression. In practice, when used in a covered bridge, the most common application, the truss is protected with outside sheathing.
The floor and roof are also trusses, but are horizontal and serve to give the truss rigidity. The bottoms of the diagonals tend to protrude below the sheathing. The Brown truss is noted for economy of materials as it can be built with very little metal.
Brown's patent claims did not actually address the economy afforded by lack of vertical members ("braces"). Instead he focused on the improved strength over previous trusses that had members ("braces" in his
The carronade was a short smoothbore, cast iron cannon, developed for the Royal Navy by the Carron Company, an ironworks in Falkirk, Scotland, UK. It was used from the 1770s to the 1850s. Its main function was to serve as a powerful, short-range anti-ship and anti-crew weapon. While considered very successful early on, carronades eventually disappeared as rifled naval artillery changed the shape of the shell and led to fewer and fewer close-range engagements.
The carronade was designed as a short-range naval weapon with a low muzzle velocity. Its invention is variously ascribed to Lieutenant General Robert Melville in 1759, or to Charles Gascoigne, manager of the Carron Company from 1769 to 1779. In its early years the weapon was sometimes called a "mellvinade" or alternatively, a "gasconade".
The reduced range allowed carronades to have a shorter length and much lighter weight than long guns. This allowed a ship to carry more carronades, or carronades of a larger calibre, than long guns, and carronades could be mounted on the upper decks, where heavy long guns could cause the ship to be top-heavy and unstable. Carronades also required a smaller gun crew, and were faster to reload
A depth charge is an anti-submarine warfare (ASW) weapon intended to destroy or cripple a target submarine by the shock of exploding near it. Most use explosives and a fuze set to go off at a preselected depth in the ocean. Depth charges can be dropped by surface ships, patrol aircraft, or helicopters. The depth charge has now largely been replaced by anti-submarine homing torpedoes.
A depth charge fitted with a nuclear warhead is known as a nuclear depth bomb. These were designed to be dropped from a patrol plane or deployed by anti-submarine missile from a surface ship, or another submarine, located a safe distance away. All nuclear anti-submarine weapons were withdrawn from service by the United States, the United Kingdom, France, Russia, and China in or around 1990. They were replaced by conventional weapons that provided ever-increasing accuracy and range as ASW technology improved.
The idea of firing charges at set depths was not new. The first attempt was by aircraft bombs attached to lanyards which would trigger their charges; a similar idea was a 16 lb (7.3 kg) guncotton charge in a lanyarded can; two of these lashed together became known as the Depth Charge Type A.
A jerrycan (also written as jerry can or jerrican) is a robust fuel container originally made from pressed steel. It was designed in Germany in the 1930s for military use to hold 20 litres (~5 US gallons) of fuel. The development of the jerrycan was a significant improvement on earlier designs, which required tools and funnels to use.
Today similar designs are used for fuel and water containers, some of which are also produced in plastic. The designs usually emulate the original steel design and are still known as jerrycans, although they have also been called "jerryjugs" (or "jerry jugs", just as jerrycan is sometimes spelled as two words as well). Generally their use is denoted by the coloring, and occasionally, imprinted labeling on the container itself. This is to prevent the mixture of different fuels, as well as preventing water containers from being contaminated with fuel or vice versa.
The US version of the jerrycan is covered by military specification MIL-C-1283 and has been produced since the early 1940s by a number of US manufacturers, according to a current manufacturer, Blitz. The National Stock Number is 7240-00-222-3088. It is considered obsolete, having been
Mauveine, also known as aniline purple and Perkin's mauve, was the first synthetic organic chemical dye, discovered serendipitously in 1856. Its chemical name is 3-amino-2,±9-dimethyl-5-phenyl-7-(p-tolylamino)phenazinium acetate.
Mauveine is a mixture of four, related aromatic compounds differing in number and placement of methyl groups. Its organic synthesis involves dissolving aniline, p-toluidine, and o-toluidine in sulfuric acid and water in a roughly 1:1:2 ratio, then adding potassium dichromate.
Mauveine A (C26H23N4X) incorporates 2 molecules of aniline, one of p-toluidine, and one of o-toluidine. Mauveine B (C27H25N4X) incorporates one molecule each of aniline, p-toluidine, and o-toluidine. In 1879, Perkin showed mauveine B related to safranines by oxidative/reductive loss of the p-tolyl group. (In fact, safranine is a 2,8-dimethyl phenazinium salt, whereas the parasafranine produced by Perkin is presumed to be the 1,8-(or 2,9) dimethyl isomer.)
Difficult to determine, mauveine's molecular structure was identified in 1994. In 2007, two more were isolated and identified: mauveine B2 (an isomer of mauveine B with methyl on different aryl group) and mauveine C (an additional
The spinning jenny is a multi-spool spinning frame. It was invented in 1764 by James Hargreaves in Stanhill, Oswaldtwistle, Lancashire in England. The device reduced the amount of work needed to produce yarn, with a worker able to work eight or more spools at once. This grew to 120 as technology advanced.
The spinning jenny is attributed to James Hargreaves. He was born in Oswaldtwistle, near Blackburn, around 1720. Blackburn was a town with a population of about 5,000, known for the production of "Blackburn greys," cloths of linen warp and cotton weft. They were usually sent to London to be printed.
At the time, cotton production could not keep up with demand, and Hargreaves spent some time considering how to improve the process. The flying shuttle had increased yarn demand by the weavers by doubling their productivity, and now the spinning jenny could supply that demand by increasing the spinners' productivity even more. The machine produced coarse thread.
The idea was developed by Hargreaves as a metal frame with eight wooden spindles at one end. A set of eight rovings was attached to a beam on that frame. The rovings when extended passed through two horizontal bars of wood that
The spinning mule was a machine used to spin cotton and other fibres in the mills of Lancashire and elsewhere from the late eighteenth to the early twentieth century. Mules were worked in pairs by a minder, with the help of two boys: the little piecer and the big or side piecer. The carriage carried up to 1320 spindles and could be 150 feet (46 m) long, and would move forward and back a distance of 5 feet (1.5 m) four times a minute. It was invented between 1775 and 1779 by Samuel Crompton. The self-acting (automatic) mule was patented by Richard Roberts in 1825. At its peak there were 50,000,000 mule spindles in Lancashire alone.
The spinning mule spins textile fibres into yarn by an intermittent process. In the draw stroke, the roving is pulled through rollers and twisted; on the return it is wrapped onto the spindle. Its rival, the throstle frame or ring frame uses a continuous process, where the roving is drawn, twisted and wrapped in one action. The mule was the most common spinning machine from 1790 until about 1900 and was still used for fine yarns until the early 1980s. In 1890, a typical cotton mill would have over 60 mules, each with 1,320 spindles, which would operate
A clapperboard is a device used in filmmaking and video production to assist in the synchronizing of picture and sound, and to designate and mark particular scenes and takes recorded during a production. The sharp "clap" noise that the clapperboard makes can be identified easily on the audio track, and the shutting of the clapstick can be identified easily on the separate visual track. The two tracks can then be precisely synchronised by matching the sound and movement. Other names for the clapperboard include clapper, clapboard, slate, slate board, sync slate, time slate, sticks, board, and marker.
When a movie's sound and picture are out of synchronization, this is known as lip flap.
The clapperboard or clapboard slate is the combination of the chalkboard slate that held information identifying the next scene and the clapstick which was used to align sound and picture. In the early days of film, one person would hold a slate for the camera with the scene information, while another clapped two hinged sticks together in front of the camera. The combination of the two into one unit made it possible for one person to perform both tasks.
Traditional clapperboards consisted of a wooden
A box kite is a high performance kite, noted for developing relatively high lift; it is a type within the family of cellular kites. The typical design has four parallel struts. The box is made rigid with diagonal crossed struts. There are two sails, or ribbons, whose width is about a quarter of the length of the box. The ribbons wrap around the ends of the box, leaving the ends and middle of the kite open. In flight, one strut is the bottom, and the bridle is tied between the top and bottom of this strut. The dihedrals of the sails help stability.
The box kite was invented in 1893 by Lawrence Hargrave, an Englishman who emigrated to Australia, as part of his attempt to develop a manned flying machine. Hargrave linked several of his box kites (Hargrave cells) together, creating sufficient lift for him to fly some 16 ft (4.9 m) off the ground. A winged variant of this kite is known as the Cody kite following its development by Samuel Cody as a platform for military observation during the Second Boer War. Military uses also involved a kite/radio transmitter combination issued to pilots during World War II for use in liferafts.
Large box kites are constructed as cellular kites. Rather
A concertina is a free-reed musical instrument, like the various accordions and the harmonica. It has a bellows and buttons typically on both ends of it. When pressed, the buttons travel in the same direction as the bellows, unlike accordion buttons which travel perpendicularly to it. Also, each button produces one note, while accordions typically can produce chords with a single button.
The concertina was developed in England and Germany, most likely independently. The English version was invented in 1829 by Sir Charles Wheatstone and a patent for an improved version was filed by him in 1844. The German version was announced in 1834 by Carl Friedrich Uhlig.
The word concertina refers to a family of hand-held bellows-driven free reed instruments constructed according to various systems. Strictly speaking: Concertinas are six sided, Aeolas are eight sided and Edeophones are twelve sided. The systems differ in:
Because the concertina was developed nearly contemporaneously in England and Germany, systems can be broadly divided into English, German, and Anglo-German types. To a player proficient in one of these systems, a concertina constructed according to a different system may be
A Fairlie is a type of articulated steam locomotive that has the driving wheels on bogies. The locomotive may be double-ended (a double Fairlie) or single ended (a single Fairlie). Fairlies are most associated with the Ffestiniog Railway in Wales.
While the Fairlie locomotive has all but disappeared, the vast majority of diesel and electric locomotives in the world today follow a form not very different from the Fairlie — two power trucks with all axles driven, and many also follow the Fairlie's double-ended concept, being capable of driving equally well in both directions.
The Fairlie was invented and patented by the Scottish engineer Robert Francis Fairlie in 1864. He had become convinced that the conventional pattern of locomotive was seriously deficient; they wasted weight on unpowered wheels (the maximum tractive effort a locomotive can exert is a function of the weight on its driving wheels) and on a tender that did nothing but carry fuel and water without contributing to the locomotive's adhesive weight. Furthermore, the standard locomotive had a front and back, and was not intended for prolonged driving in reverse, thus requiring a turntable or wye at every
A feature film is a film with a full-length running time. According to the Academy of Motion Picture Arts and Sciences, American Film Institute, and British Film Institute, a feature film runs for 40 minutes or longer, while the Screen Actors Guild states that it is 80 minutes or longer.
The majority of feature films are between 90 and 210 minutes long. The Story of the Kelly Gang was the first feature film based on length, and was released in Australia in 1906. The first feature-length adaptation was Les Misérables which was released in 1909.
Feature films for children are usually between 60 and 120 minutes. Other early feature films include a version of Oliver Twist (1912), Richard III (1912) and From the Manger to the Cross (1912).
Many feature films tend to be adaptations of literary works. Notable feature length adaptations include The Godfather, Gone With the Wind, Dracula, Forrest Gump and The Lord of the Rings trilogy.
The Academy of Motion Picture Arts and Sciences, the American Film Institute, and the British Film Institute all define a feature as a film with a running time of 40 minutes or longer. The Centre National de la Cinématographie in France defines it as a 35 mm
The MMR vaccine is an immunization shot against measles, mumps, and rubella (also called German measles). It was first developed by Maurice Hilleman while at Merck in the late 1960s.
The vaccine is a mixture of three live attenuated viruses, administered via injection. The shot is generally administered to children around the age of one year, with a second dose before starting school (i.e. age 4/5). The second dose is a dose to produce immunity in the small number of persons (2–5%) who fail to develop measles immunity after the first dose. In the United States, the vaccine was licensed in 1971 and the second dose was introduced in 1989. It is widely used around the world; since introduction of its earliest versions in the 1970s, over 500 million doses have been used in over 60 countries. As with all vaccinations, long-term effects and efficacy are subject to continuing study. The vaccine is sold by Merck as M-M-R II, GlaxoSmithKline Biologicals as Priorix, Serum Institute of India as Tresivac, and Sanofi Pasteur as Trimovax.
It is usually considered a childhood vaccination. However, it is also recommended for use in some cases of adults with HIV.
Before the widespread use of a
A Pythagorean cup (also known as a Pythagoras cup, a Greedy Cup or a Tantalus cup) is a form of drinking cup which forces its user to imbibe only in moderation. Credited to Pythagoras of Samos, it allows the user to fill the cup with wine up to a certain level. If the user fills the cup only to that level, the imbiber may enjoy a drink in peace. If the imbiber exhibits gluttony, however, the cup spills its entire contents out the bottom (onto the lap of the immodest drinker).
A Pythagorean cup looks like a normal drinking cup, except that the bowl has a central column in it – giving it a shape like a Bundt pan in the center of the cup. The central column of the bowl is positioned directly over the stem of the cup and over the hole at the bottom of the stem. A small open pipe runs from this hole almost to the top of the central column, where there is an open chamber. The chamber is connected by a second pipe to the bottom of the central column, where a hole in the column exposes the pipe to (the contents of) the bowl of the cup.
When the cup is filled, liquid rises through the second pipe up to the chamber at the top of the central column, following Pascal's principle of
A Robertson screwdriver (also called a square drive screwdriver) is a type of screwdriver with a square-shaped tip with a slight taper (in the same way that straight blade, Phillips, hex, and Torx drivers have flat, x-shaped, hexagonal, and hexagrammal tips, respectively). Robertson screws are used mainly in Canada (where they are very common), though they can be found elsewhere.
Canadian P.L. Robertson invented the Robertson screw and screwdriver in 1908. He received a patent in 1909, and later applied for and received other patents. The last patent expired in 1964. An earlier square drive wood screw patent, U.S. Patent 161,390, was issued to Allan Cummings on March 30th, 1875.
Robertson screwdrivers are easy to use one-handed, since the tapered socket retains the screw, even if it is shaken. They also allow for the use of angled screw drivers and trim head screws. The socket-headed Robertson screws are self-centring, reduce cam-out, stop a power tool when set, and can be removed even if painted-over or old and rusty. In industry, they speed up production and reduce product damage.
Robertson had licensed the screw in England, but the party with which he was dealing intentionally
Catch Me Who Can was the fourth and last steam railway locomotive created by Richard Trevithick, (after those at Coalbrookdale, Penydarren ironworks and Wylam colliery). Built in 1808 by Rastrick and Hazledine at their foundry in Bridgnorth, England. It was demonstrated to the public at a "steam circus" organized by Trevithick on a circular track in Bloomsbury, just south of the present-day Euston Square tube station in London.
The locomotive reached a top speed of 12 mph (19 km/h). It proved too heavy, however, for the relatively brittle cast-iron rails then in use and Trevithick closed his exhibition after a broken rail caused a derailment.
The mechanical arrangement of Catch Me Who Can was simpler than the previous locomotives. The horizontal cylinder, flywheel, and geared drive were replaced by a vertical cylinder, still encased within the boiler, driving one pair of wheels directly by means of connecting rods. The boiler was Trevithick's usual return-flue type, with an internal firebox.
A replica is under construction by the Trevithick 200 charity at the Severn Valley Railway workshops, close to the site where the original locomotive was built. As of December 2011, it is
The Hippocratic bench or scamnum was a device invented by Hippocrates (c. 460 BC–380 BC) which used tension to aid in setting bones. It is a forerunner of the traction devices used in modern orthopedics, as well as of the rack, an instrument of torture.
The patient would lie on a bench, at an adjustable angle, and ropes would be tied around his arms, waist, legs or feet, depending on the treatment needed. Winches would then be used to pull the ropes apart, correcting curvature in the spine or separating an overlapping fracture.
In recent years, a similar non-surgical procedure known as VAX-D (short for Vertebral Axial Decompression) has been developed for treating certain patients with lower back pain. Patients undergoing VAX-D are fitted with a special pelvic harness and then placed on the VAX-D table. The device then applies controlled tension along the axis of the spinal column, while the harness assists in providing decompression of the lumbar spine. The decompression process is controlled by computer program with supervision by a human technician. The VAX-D process is claimed to be useful in treating cases of sciatica, degenerative disc disease, and herniated discs.
Medical gloves are disposable gloves used during medical examinations and procedures that help prevent contamination between caregivers and patients. Medical gloves are made of different polymers including latex, nitrile rubber, vinyl and neoprene; they come unpowdered, or powdered with cornstarch to lubricate the gloves, making them easier to put on the hands. Cornstarch replaced tissue-irritating Lycopodium powder and talc, but since even cornstarch can impede healing if it gets into tissues (as during surgery), unpowdered gloves are being used more often during surgery and other sensitive procedures. Special manufacturing processes are used to compensate for the lack of powder. There are two main types of gloves: exam and surgical. Surgical gloves have more precise sizing with a better precision and sensitivity and are made to a higher standard.
In 1890 William Stewart Halsted was the first to use sterilized medical gloves when he was at Johns Hopkins University. With the publication of germ theory Halsted was using carbolic acid, introduced by Joseph Lister, to sterilize his hands and his nurse's hands. She was sensitive to the chemical, and it was damaging the skin on her
A thrust bearing is a particular type of rotary bearing. Like other bearings they permit rotation between parts, but they are designed to support a high axial load while doing this.
Thrust bearings come in several varieties.
They are commonly used in automotive, marine, and aerospace applications.
Thrust bearings are used in cars because the forward gears in modern car gearboxes use helical gears which, while aiding in smoothness and noise reduction, cause axial forces that need to be dealt with. The double helical or herringbone gear balances the thrust caused by normal helical gears.
One specific thrust bearing in an automobile is the clutch "throw out" bearing, sometimes called the clutch release bearing.
Fluid-film thrust bearings were invented by Australian engineer George Michell (pronounced Mitchell) who patented his invention in 1905. Michell bearings contain a number of sector-shaped pads, arranged in a circle around the shaft, and which are free to pivot. These create wedge-shaped regions of oil inside the bearing between the pads and a rotating disk, which support the applied thrust and eliminate metal-on-metal contact.
Michell's invention was notably applied to the
The World Wide Web (abbreviated as WWW or W3, commonly known as the Web), is a system of interlinked hypertext documents accessed via the Internet. With a web browser, one can view web pages that may contain text, images, videos, and other multimedia, and navigate between them via hyperlinks.
Using concepts from his earlier hypertext systems like ENQUIRE, British engineer, computer scientist and at that time employee of CERN, Sir Tim Berners-Lee, now Director of the World Wide Web Consortium (W3C), wrote a proposal in March 1989 for what would eventually become the World Wide Web. At CERN, a European research organization near Geneva situated on Swiss and French soil, Berners-Lee and Belgian computer scientist Robert Cailliau proposed in 1990 to use hypertext "to link and access information of various kinds as a web of nodes in which the user can browse at will", and they publicly introduced the project in December of the same year.
In the May 1970 issue of Popular Science magazine, Arthur C. Clarke predicted that satellites would someday "bring the accumulated knowledge of the world to your fingertips" using a console that would combine the functionality of the Xerox, telephone,
The ambrotype (from Ancient Greek: ἀνβροτός — “immortal”, and τύπος — “impression”) or amphitype is a photograph that creates a positive image on a sheet of glass using the wet plate collodion process. In the United States, ambrotypes first came into use in the early 1850s. The wet plate collodion process was invented just a few years before that by Frederick Scott Archer, but ambrotypes used the plate image as a positive, instead of a negative. In 1854, James Ambrose Cutting of Boston took out several patents relating to the process and may be responsible for coining the term "ambrotype".
In the United Kingdom it was called collodion positive: one side of a very clean glass plate is covered with a thin layer of collodion, then dipped in a silver nitrate solution. The plate is exposed to the subject while still wet. (Exposure times vary from five to sixty seconds or more depending on the amount of available light.) The plate is then developed and fixed. The resulting negative, when viewed by reflected light against a black background, appears to be a positive image: the clear areas look black, and the exposed, opaque areas appear light. This effect is achieved by coating one side
Detective fiction is a sub-genre of crime fiction and mystery fiction in which an investigator (often a detective), either professional or amateur, investigates a crime, often murder.
Some scholars have suggested that some ancient and religious texts bear similarities to what would later be called detective fiction. In the Old Testament story of Susanna and the Elders (Daniel 13; in the Protestant Bible this story is found in the apocrypha), the story told by two witnesses breaks down when Daniel cross-examines them. The author Julian Symons has commented on writers who see this as a detective story, arguing that "those who search for fragments of detection in the Bible and Herodotus are looking only for puzzles" and that these puzzles are not detective stories. In the play Oedipus Rex by Ancient Greek playwright Sophocles, the title character discovers the truth about his origins after questioning various witnesses. Although "Oedipus's enquiry is based on supernatural, pre-rational methods that are evident in most narratives of crime until the development of Enlightenment thought in the seventeenth and eighteenth centuries" it has "all of the central characteristics and formal
A hydrofoil is a foil which operates in water. They are similar in appearance and purpose to airfoils.
Hydrofoils can be artificial, such as the rudder or keel on a boat, the diving planes on a submarine, a surfboard fin, or occur naturally, as with fish fins, the flippers of aquatic mammals, the wings of swimming seabirds, or other creatures like the sand dollar.
The term "hydrofoil" is commonly used for the wing-like structure mounted on struts below the hull of a variety of boats (see illustration), which lifts the boat out of the water during forward motion, in order to reduce hull drag; as such, the term "hydrofoil" is often used to refer to boats using hydrofoil technology. Most of this article is about this type of hydrofoil.
As a hydrofoil-equipped watercraft increases in speed, the hydrofoil elements below the hull(s) develop enough lift to raise the hull up and out of the water. This results in a great reduction in hull drag, and a further corresponding increase in speed.
A wider adoption of the technical innovations of hydrofoils is prevented by the increased complexity of building and maintaining them. Hydrofoils are generally prohibitively more expensive than
A lightning rod (US, AUS) or lightning conductor (UK) is a metal rod or metallic object mounted on top of a building, electrically bonded using a wire or electrical conductor to interface with ground or "earth" through an electrode, engineered to protect the building in the event of lightning strike. If lightning targets the building it will preferentially strike the rod and be conducted to ground through the wire, instead of passing through the building, where it could start a fire or cause electrocution.
A lightning rod is a single component in a lightning protection system. Lightning rods are also called finials, air terminals or strike termination devices. The lighting rod requires a connection to earth to perform its protective function. Lightning rods come in many different forms, including hollow, solid, pointed, rounded, flat strips or even bristle brush-like: copper or aluminum. The main attribute of all lightning rods is they are conductive.
Copper and its alloys are the most common materials used in lightning protection. Copper effectively and rapidly facilitates the transmission of lightning energy to the ground because of its excellent electrical conductivity and
The Sinclair ZX80 is a home computer brought to market in 1980 by Science of Cambridge Ltd. (later to be better known as Sinclair Research). It is notable for being the first computer (unless you consider the MK14) available in the United Kingdom for less than a hundred pounds (£99.95). It was available in kit form, where purchasers had to assemble and solder it together and as a ready-built version at a slightly higher cost. The ZX80 was very popular straight away, and for some time there was a waiting list of several months for either version of the machine.
The ZX80 was named after the Z80 processor with the 'X' for "the mystery ingredient".
Internally, the machine was designed by Jim Westwood around a Z80 central processing unit with a clock speed of 3.25 MHz, and was equipped with 1 kB of static RAM and 4 kB of read-only memory (ROM). The ZX80 was designed around readily available TTL chips; the only proprietary technology was the firmware. While the successor ZX81 used a semi-custom chip (a ULA or Uncommitted Logic Array), this merely combined the functions of the earlier hardware onto a single chip — the hardware and system programs (except the BASIC versions) were very
Kin-Ball, also known as Omnikin, is a team sport created in Quebec, Canada in 1986 by Mario Demers, a physical education professor. The International Kin-Ball Federation counts 3.8 million participants, primarily from Canada, the U.S., Japan, Belgium, France, Switzerland, Spain, Germany, Denmark and Malaysia.
Games have three periods lasting between 7 to 15 minutes each, depending on the age level of the participants, with a one-minute intermission between each period. At the beginning of each period the ball is put into play from the centre of the gym by the team with the fewest points. The team with the most points at the end of the three periods wins the game.
Teams are composed of 4 players (with up to 4 substitutes), all of which wear a jersey or pinny of a different colour, with grey, pink and black being the official colours internationally, except in Quebec where blue replaced pink in 2004.
Each team has 4 players. When the game starts, The player in center will throw the ball up while yelling "Omnikin" and the corresponding color of a team and that team must catch the ball before it touches the floor.
The team must have 3 players holding the ball from below
The Phoenix Iron Works (1855: Phoenix Iron Company; 1949: Phoenix Iron & Steel Company; 1955: Phoenix Steel Corporation), located in Phoenixville, Pennsylvania, was a significant manufacturer of iron and related products during the 19th century and early 20th century. Phoenix Iron Company was a major producer of cannons for the Union Army during the American Civil War. The company also produced the Phoenix column, a significant advance in construction material.
Phoenix Iron Works is a core component of the Phoenixville Historic District, a National Register of Historic Places site and in 2006 was recognized as a Historic Landmark by ASM International.
Originally founded in 1790 to produce nails and purchased in 1812 by New Jersey industrialist Robert Waln, the Phoenix Iron Company (later renamed the Phoenix Iron Works) produced pig iron, wrought iron, and other iron-related materials and end products. As the complex grew, it featured a huge blast furnace and puddling furnace, an adjacent iron foundry, warehouses, ancillary buildings, and associated equipment. In 1825, the company was the first to successfully generate steam through the burning of anthracite coal to heat water.
The stump-jump plough is a kind of plough invented in South Australia in the late 19th century by Richard Bowyer Smith to solve the particular problem of preparing mallee lands for cultivation.
Mallee scrub originally covered large parts of southern Australia, and when farmers moved into these areas they found it peculiarly difficult to clear the land. After the trees were cut down, the roots energetically produced regrowth. These young shoots and the old roots could be killed by repeated burning (see below), but the large roots remained in the ground, making it impossible to plough the soil. Grubbing the roots out was a slow and labour-intensive activity, and the problem was seriously hindering agricultural expansion.
In South Australia, land was being offered under the Scrub Act of 1866 to farmers on lease, with the option of purchasing after 21 years at the price of £1 per acre. However, grubbing the scrublands was proving costly, at approximately £2 per acre, and solutions to the problem were desperately sought.
The situation had grown so frustrating by 1878 that the South Australian government offered a reward of £200 to anyone who could develop an effective mechanical stump
The sun and planet gear (also called the planet and sun gear) was a method of converting reciprocal motion to rotary motion and was utilised in a reciprocating steam engine.
It was invented by the Scottish engineer William Murdoch, an employee of Boulton and Watt, but was patented by James Watt in October 1781. It was invented to bypass the patent on the crank, held by James Pickard. It played an important part in the development of devices for rotation in the Industrial Revolution.
The sun and planet gear converted the vertical motion of a beam, driven by a steam engine, into circular motion using a 'planet', a cogwheel fixed at the end of the connecting rod (connected to the beam) of the engine. With the motion of the beam, this revolved around, and turned, the 'sun', a second rotating cog fixed to the drive shaft, thus generating rotary motion. An interesting feature of this arrangement, when compared to that of a simple crank, is that when both sun and planet have the same number of teeth, the drive shaft completes two revolutions for each double stroke of the beam instead of one. Note that the planet gear is fixed to the connecting rod and thus does not rotate around its own
The ZX Spectrum (pronounced "Zed-Ex") is an 8-bit personal home computer released in the United Kingdom in 1982 by Sinclair Research Ltd.
Referred to during development as the ZX81 Colour and ZX82, the machine was launched as the ZX Spectrum by Sinclair to highlight the machine's colour display, compared with the black-and-white of its predecessor, the ZX81. The Spectrum was ultimately released as eight different models, ranging from the entry level model with 16 kB RAM released in 1982 to the ZX Spectrum +3 with 128 kB RAM and built in floppy disk drive in 1987; together they sold in excess of 5 million units worldwide (not counting numerous clones).
The Spectrum was among the first mainstream audience home computers in the UK, similar in significance to the Commodore 64 in the USA. The introduction of the ZX Spectrum led to a boom in companies producing software and hardware for the machine, the effects of which are still seen; some credit it as the machine which launched the UK IT industry. Licensing deals and clones followed, and earned Clive Sinclair a knighthood for "services to British industry".
The Commodore 64, BBC Microcomputer and later the Amstrad CPC range were major
A flight recorder is an electronic recording device placed in an aircraft for the purpose of facilitating the investigation of an aircraft accident or incident. For this reason, flight recorders are required to be capable of surviving the conditions likely to be encountered in a severe aircraft accident. They are typically specified to withstand an impact of 3400 g and temperatures of over 1,000 °C (1,832 °F) (as required by EUROCAE ED-112). There are two common types of flight recorder, the flight data recorder (FDR) and the cockpit voice recorder (CVR). In some cases, the two recorders may be combined in a single FDR/CVR unit.
Since the 1970s most large civil jet transports have been additionally equipped with a "quick access recorder" (QAR). This records data on a removable storage medium. Access to the FDR and CVR is necessarily difficult because of the requirement that they survive an accident. They also require specialized equipment to read the recording. The QAR recording medium is readily removable and is designed to be read by equipment attached to a standard desktop computer. In many airlines the quick access recordings are scanned for 'events', an event being a
The Pilot ACE was one of the first computers built in the United Kingdom, at the National Physical Laboratory (NPL) in the early 1950s.
It was a preliminary version of the full ACE, which had been designed by Alan Turing. After Turing left NPL (in part because he was disillusioned by the lack of progress on building the ACE), James H. Wilkinson took over the project, Harry Huskey helped with the design. The Pilot ACE ran its first program on May 10, 1950 and was demonstrated to the press in December 1950.
Although originally intended as a prototype, it became clear that the machine was a potentially very useful resource, especially given the lack of other computing devices at the time. After some upgrades to make operational use practical, it went into service in late 1951, and saw considerable operational service over the next several years. One reason the ACE was useful is that it was able to perform Floating point arithmetic necessary for scientific calculations. Wilkinson tells the story of how this came to be. The pilot ACE was built without hardware for multiplication or long division, in contrast to other computers at that time. The ACE started out using fixed-point
The slide rule, also known colloquially (in the US) as a slipstick, is a mechanical analog computer. The slide rule is used primarily for multiplication and division, and also for functions such as roots, logarithms and trigonometry, but is not normally used for addition or subtraction.
Slide rules come in a diverse range of styles and generally appear in a linear or circular form with a standardized set of markings (scales) essential to performing mathematical computations. Slide rules manufactured for specialized fields such as aviation or finance typically feature additional scales that aid in calculations common to that field.
William Oughtred and others developed the slide rule in the 17th century based on the emerging work on logarithms by John Napier. Before the advent of the pocket calculator, it was the most commonly used calculation tool in science and engineering. The use of slide rules continued to grow through the 1950s and 1960s even as digital computing devices were being gradually introduced; but around 1974 the electronic scientific calculator made it largely obsolete and most suppliers left the business.
In its most basic form, the slide rule uses two logarithmic
Waterproof fabrics are fabrics that are inherently, or have been treated to become, resistant to penetration by water and wetting. The term "waterproof" refers to conformance to a governing specification and specific conditions of a laboratory test method. They are usually natural or synthetic fabrics that are laminated to or coated with a waterproofing material such as rubber, polyvinyl chloride (PVC), polyurethane (PU), silicone elastomer, fluoropolymers, and wax. Examples include the rubberised fabric used in Mackintosh jackets, sauna suits and inflatable boats. They are even used for footballs and glasses.
(Alternative spellings include "waterproof breathable" and "waterproof-breathable".)
Waterproof/breathable fabrics resist liquid water passing through, but allow water vapour to pass through. Their ability to block out rain and snow while allowing vapour from sweat to evaporate leads to their use in rainwear, waterproof outdoor sports clothing, tents, and other applications.
Standard laboratory testing protocols define the performance of these fabrics. Water resistance is measured by the amount of water, in mm, which can be suspended above the fabric before water seeps
In his book A New Kind of Science, Stephen Wolfram described a universal 2-state 5-color Turing machine, and conjectured that a particular 2-state 3-color Turing machine (hereinafter (2,3) Turing machine) might be universal as well.
On May 14, 2007, Wolfram announced a $25,000 prize to be won by the first person to prove or disprove the universality of the (2,3) Turing machine. According to Wolfram, the purpose of the prize was to encourage research to help answer foundational questions associated with the structure of what he calls the "computational universe". On 24 October 2007, it was announced that the prize had been won by Alex Smith, a student in electronics and computing at the University of Birmingham.
In each state, the machine reads the bit under the head and executes the instructions in the following table (where Pn prints bit n, L and R are left and right respectively, and A and B mean "switch to that state").
The (2,3) Turing machine:
Minsky (1967) briefly argues that standard (2,2) machines cannot be universal; thus, it might seem that the (2,3) Turing machine would be the smallest possible universal Turing machine (in terms of number of states times number of
Bovril is the trademarked name of a thick, salty meat extract, developed in the 1870s by John Lawson Johnston and sold in a distinctive, bulbous jar. It is made in Burton upon Trent, Staffordshire, owned and distributed by Unilever UK.
Bovril can be made into a drink by diluting with hot water, or less commonly with milk. It can also be used as a flavouring for soups, stews or porridge, or spread on bread, especially toast, rather like Marmite.
The first part of the product's name comes from Latin bos meaning "ox" or "cow." Johnston took the -vril suffix from Bulwer-Lytton's then-popular "lost race" novel The Coming Race (1870), whose plot revolves around a superior race of people, the Vril-ya, who derive their powers from an electromagnetic substance named "Vril."
In 1870, in the war against the Prussians, Napoleon III ordered one million cans of beef to feed his troops. The task of providing all this beef went to a Scotsman living in Canada named John Lawson Johnston. Large quantities of beef were available across the British Dominions and South America, but its transport and storage were problematic. Therefore Johnston created a product known as 'Johnston's Fluid Beef,' later
The human papilloma virus (HPV) vaccine prevents infection with certain species of human papillomavirus associated with the development of cervical cancer, genital warts, and some less common cancers. Two HPV vaccines are currently on the market: Gardasil and Cervarix.
Both vaccines protect against the two HPV types (HPV-16 and HPV-18) that cause 70% of cervical cancers, 80% of anal cancers, 60% of vaginal cancers, and 40% of vulvar cancers. These HPV types also cause most HPV induced oral cancers, and some other rare genital cancers. Gardasil also protects against the two HPV types (HPV-6 and HPV-11) that cause 90% of genital warts.
Both vaccines have been shown to prevent potentially precancerous lesions of the cervix. Gardasil has been shown to prevent potential precursors to anal, vulvar, vaginal, and penile cancers. HPV vaccines are expected to protect against HPV induced cancers of these areas as well as HPV induced oral cancers.
The World Health Organization (WHO), as well as public health officials in Australia, Canada, Europe, and the United States recommend vaccination of young women against HPV to prevent cervical cancer, and to reduce the number of treatments for
The Walker Linerlock is a liner lock knife locking refinement developed, trademarked, and popularized by custom knifemaker Michael Walker in 1980 for use on folding knives. Like older liner locks, when the blade of the knife is in the opened position, it is held in place by a leaf spring (also called a lockbar) that butts up against the tang of the blade to prevent the blade from closing. To release the lock, the user must press the lockbar back toward the handle side, at which time the blade is allowed to close. In the closed position the lockbar rests alongside the handle and the blade.
Liner lock knives have been around since the late 19th century. The Cattaraugus liner locking patent, 825,093 was issued in July 3, 1906. After 1923 when the patent expired, it was used by other manufacturers such as in the common military and lineman's issue two-blade electrician’s knife; the Camillus TL-29 for the locking screwdriver-stripper blade, until 2007 when the Camillus Cutlery Company went out of business.
Michael Walker refined and popularized the design, eventually securing a trademark for the name "linerlock." Walker's main contribution to improve the design was to facilitate true
An assisted-opening knife is a type of folding knife which uses an internal mechanism to finish the opening of the blade once the user has partially opened it using a flipper or thumbstud attached to the blade.
The first assisted opening knife was designed by Blackie Collins in 1995 and was named the "Strut-and-Cut"; it was based on the strut of his Ducati motorcycle. A similar concept was developed years later by knifemaker Ken Onion with Onion's idea based on a similar mechanism in his Harley Davidson motorcycle. Onion applied for a patent on his design in 1998.
When the knife is in the closed position, the blade is held in place by means of torsion springs and an additional blade lock (optional). As the user applies manual pressure to the thumbstud to open the knife, a mechanism such as a torsion spring moves along a track in the liner and rapidly rotates the blade into the open and locked position.
Although commonly confused with switchblade knives, there is a difference. While a switchblade can be opened automatically with the push of a button, the user of an assisted-opening knife must apply some manual pressure to the blade at the thumb stud or flipper.
Because the blade
Continuous tracks or caterpillar tracks are a system of vehicle propulsion in which a continuous band of treads is driven by two or more wheels. This band is typically made of modular steel plates in the case of military vehicles, or rubber reinforced with steel wires in the case of lighter agricultural or construction vehicles. The large surface area of the tracks distributes the weight of the vehicle better than steel or rubber tires on an equivalent vehicle, enabling a continuous tracked vehicle to traverse soft ground with less likelihood of becoming stuck due to sinking. The prominent treads of the metal plates are both hard-wearing and damage resistant, especially in comparison to rubber tires. The aggressive treads of the tracks provide good traction in soft surfaces but can damage paved surfaces. Special tracks that incorporate rubber pads can be installed for use on paved surfaces to prevent the damage that can be caused by all-metal tracks.
Continuous tracks can be traced back as far as 1770 and today are commonly used on a variety of vehicles including bulldozers, excavators, tanks, and tractors, but can be found on any vehicle used in an application that can benefit
A goaltender mask, commonly referred to as a goalie mask or a hockey mask, is a mask worn by ice hockey, inline hockey, and field hockey goaltenders to protect the head from injury. Jacques Plante was the first goaltender to create and use a practical mask in 1959. Plante's mask was a piece of fiberglass that was contoured to his face. This mask later evolved into a helmet/cage combination, and single piece full fiberglass mask. Today, the full fiberglass mask is the more popular option because it is safer.
The first goaltender mask was a fiberglass fencing mask donned in February 1927 by Queen's University netminder Elizabeth Graham, mainly to protect her teeth. In 1930, the first crude leather model of a mask (actually an American football "nose-guard") was worn by Clint Benedict to protect his broken nose. After recovering from the injury, he abandoned the mask, never wearing one again in his career. At the 1936 Winter Olympics, Teiji Honma wore a crude mask, similar to the one worn by baseball catchers. The mask was made of leather, and had a wire cage which protected the face, as well as Honma's large circular glasses.
It was not until 1959 that a goaltender wore a mask
The hansom cab is a kind of horse-drawn carriage designed and patented in 1834 by Joseph Hansom, an architect from York. The vehicle was developed and tested by Hansom in Hinckley, Leicestershire, England. Originally called the Hansom safety cab, it was designed to combine speed with safety, with a low centre of gravity for safe cornering. Hansom's original design was modified by John Chapman and several others to improve its practicability, but retained Hansom's name.
Cab is a shortening of cabriolet, reflecting the design of the carriage. It replaced the hackney carriage as a vehicle for hire; with the introduction of clockwork mechanical taximeters to measure fares, the name became taxicab.
Hansom cabs enjoyed immense popularity as they were fast, light enough to be pulled by a single horse (making the journey cheaper than travelling in a larger four-wheel coach) and were agile enough to steer around horse-drawn vehicles in the notorious traffic jams of nineteenth-century London. There were up to 7500 hansom cabs in use at the height of their popularity and they quickly spread to other cities in the United Kingdom, as well as continental European cities, particularly Paris,
A Hills Hoist is a height-adjustable rotary clothes line, manufactured in Adelaide, South Australia by Lance Hill since 1945. The Hills Hoist and similar rotary clothes hoists remain a common fixture in many backyards in Australia and New Zealand. They are considered one of Australia's most recognisable icons, and are used frequently by artists as a metaphor for Australian suburbia in the 1950s and 1960s. Although originally a product name, the term "Hills Hoist" became synonymous with rotary clothes hoists in general, throughout Australia.
As early as 1895 Colin Stewart and Allan Harley of Sun Foundry in Adelaide applied for a patent for an ‘Improved Rotary and Tilting Clothes Drying Rack’. In their design the upper clothes line frame tilted to allow access to the hanging lines. Gilbert Toyne of Geelong patented four rotary clothes hoists designs between 1911 and 1946. Toyne’s first patented clothes hoist was sold though the Aeroplane Clothes Hoist Company established in 1911. It was Toyne’s 1925 all-metal model (Australian Patent No. 24553/25) with its enclosed crown wheel-and-pinion winding mechanism that defined clothes hoist designs for decades to follow.
Lance Hill began to
Magnetic-core memory was the predominant form of random-access computer memory for 20 years (circa 1955–75). It uses tiny magnetic toroids (rings), the cores, through which wires are threaded to write and read information. Each core represents one bit of information. The cores can be magnetized in two different ways (clockwise or counterclockwise) and the bit stored in a core is zero or one depending on that core's magnetization direction. The wires are arranged to allow an individual core to be set to either a "one" or a "zero", and for its magnetization to be changed, by sending appropriate electric current pulses through selected wires. The process of reading the core causes the core to be reset to a "zero", thus erasing it. This is called destructive readout.
Such memory is often just called core memory, or, informally, core. Although core memory had been superseded by semiconductor memory by the end of the 1970s, memory is still occasionally called "core"; in particular, a file recording the contents of memory after a system error is usually called a core dump.
Frederick Viehe applied for various patents on the use of transformers for building digital logic circuits in place
Portland cement (often referred to as OPC, from Ordinary Portland Cement) is the most common type of cement in general use around the world because it is a basic ingredient of concrete, mortar, stucco and most non-specialty grout. It usually originates from limestone. It is a fine powder produced by grinding Portland cement clinker (more than 90%), a limited amount of calcium sulfate (which controls the set time) and up to 5% minor constituents as allowed by various standards such as the European Standard EN197-1:
Portland cement clinker is a hydraulic material which shall consist of at least two-thirds by mass of calcium silicates (3 CaO·SiO2 and 2 CaO·SiO2), the remainder consisting of aluminium- and iron-containing clinker phases and other compounds. The ratio of CaO to SiO2 shall not be less than 2.0. The magnesium oxide content (MgO) shall not exceed 5.0% by mass.
(The last two requirements were already set out in the German Standard, issued in 1909).
ASTM C 150 defines portland cement as "hydraulic cement (cement that not only hardens by reacting with water but also forms a water-resistant product) produced by pulverizing clinkers consisting essentially of hydraulic calcium
The Maxim gun was the first self-powered machine gun, invented by the American-born British inventor Sir Hiram Stevens Maxim in 1884. It has been called "the weapon most associated with [British] imperial conquest".
The mechanism of the Maxim gun employed one of the earliest recoil operated firing systems in history. The idea is that the energy from the recoil is used, in lieu of a locked bolt or a lever mechanism, to eject each spent cartridge and insert the next one. This made it vastly more efficient and less labour intensive than previous rapid-firing guns, such as the Gatling, Gardner, or Nordenfelt guns that relied on actual mechanical cranking, as well as decreasing the gas buildup in the barrel, allowing the gun to fire more bullets over an extended period of time without overheating the barrel. The Maxim gun design still required water cooling, however, which gave it additional points of failure and made it more difficult to operate and heavier per calibre, compared to most later heavy machine guns. Trials demonstrated the Maxim could fire 600 rounds per minute, equivalent to the firepower of about 30 contemporary breech-loading bolt-action rifles. Compared to modern
The modern version was invented during the early 20th century in Norway. The cheese slicer's mass production started in 1927. The design was based on the carpenter's plane.
This style of slicer is very common in the Nordic countries, the Netherlands, Belgium, Germany, France, and Switzerland. The success of the cheese slicer in these countries is based on the fact that cheese is eaten mainly sliced, on bread and that the most traditional cheese varieties in these countries are hard enough to be sliced.
The Chiko Roll is an Australian savoury snack, inspired by the Chinese egg roll and spring rolls. It was designed to be easily eaten on the move without a plate or cutlery. The Chiko roll consists of beef, celery, cabbage, barley, carrot, corn, onion, green beans, and spices in a tube of egg, flour and dough which is then deep-fried. The wrap was designed to be unusually thick so it would survive handling at football matches. It was originally nicknamed a "Chinco roll" referring to a racial slur as it was modelled on an Asian competitor's Chop Suey Roll, but later renamed to a more politically correct "Chiko Roll". At the peak of their popularity in the 1960s and 1970s, forty million Chiko Rolls were sold annually in Australia, and the product has been described as an Australian cultural icon.
The Chiko Roll was developed by Frank McEncroe, a boilermaker from Bendigo who turned to catering at football matches and other outdoor events. In 1950, McEncroe saw a competitor selling Chinese chop suey rolls outside Richmond Cricket Ground and decided to add a similar product to his own line. McEncroe felt that the Chinese rolls were too flimsy to be easily handled in an informal outdoor
The LP (Long Play), or long-playing microgroove record, is a format for phonograph (gramophone) records, an analog sound storage medium. Introduced by Columbia Records in 1948, it was soon adopted as a new standard by the entire record industry. Apart from relatively minor refinements and the important later addition of stereophonic sound capability, it has remained the standard format for vinyl "albums" up to the present.
At the time the LP was introduced, nearly all phonograph records for home use were made of an abrasive (and therefore noisy) shellac compound, employed a much larger groove, and played at approximately 78 rpm, limiting the playing time of a 12-inch record to less than five minutes per side. The new product was a 12 or 10-inch fine-grooved disc made of vinyl and played with a smaller-tipped "microgroove" stylus at a speed of 33⅓ rpm. Each side of a 12-inch LP could play for more than 20 minutes. Only the microgroove standard was truly new, as both vinyl and the 33⅓ rpm speed had been used for special purposes for many years, as well as in one unsuccessful earlier attempt to introduce a long-playing record for home use. Although the LP was especially suited to
Roto-Rooter is a United States company which originally specialized in clearing tree roots and other obstructions from sewer lines. Today it offers a broad array of plumbing repair, sewer and drain cleaning services utilizing its patented, proprietary Roto-Rooter machine.
In the late 1920s, Samuel Oscar Blanc (1883–1964) was motivated by a stubborn clogged drain in his son's (Milton L. Blanc) Des Moines, Iowa apartment to seek a better solution.
By 1933, Milton & Samuel Blanc had fashioned a sewer-cleaning machine from a washing machine motor, roller skate wheels and a 3/8" steel cable. The cable rotated sharp blades to cut tree roots out of sewer lines, eliminating the tedious and expensive need to dig. Blanc's wife, Lettie (née Lettie Jensen), called his invention, a heavy-duty plumber's snake, the "Roto-Rooter."
By the mid-1930s, Blanc was selling "Roto-Rooter" machines for $250. Many who were eager for work in the midst of the Great Depression started their own Roto-Rooter businesses throughout the upper Midwest, the Great Plains and the Northeast.
Roto-Rooter guaranteed results without having to dig up the lawn to reach underground sewer pipes.
In 1980, the Blanc family sold
A vacuum flask (also known as a Dewar flask, Dewar bottle or Thermos) is an insulating storage vessel which keeps its contents hotter or cooler than its surroundings. Invented by Sir James Dewar in 1892, the vacuum flask consists of two flasks, placed one within the other and joined at the neck. The gap between the two flasks is partially evacuated of air, creating a near-vacuum which prevents heat transfer by conduction or convection.
Vacuum flasks are used domestically to keep beverages hot or cold for extended periods, and for many purposes in industry.
The vacuum flask was invented by Scottish physicist and chemist Sir James Dewar in 1892 and is sometimes referred to as a Dewar flask or Dewar bottle after its inventor. The first vacuum flasks for commercial use were made in 1904 when a German company, Thermos GmbH, was founded. Dewar failed to register a patent for his invention and it was subsequently patented by Thermos, to whom Dewar lost a court case in claiming the rights to the invention.
"Thermos" remains a registered trademark in some countries, but was declared a genericized trademark in the U.S. in 1963 as it is colloquially synonymous with vacuum flasks in
The water fuel cell is a purported free energy device invented by American Stanley Allen Meyer (August 24, 1940 – March 21, 1998). He claimed that an automobile retrofitted with the device could use water as fuel instead of gasoline. The fuel cell purportedly split water into its component elements, hydrogen and oxygen. The hydrogen was then burned to generate energy, a process that reconstituted the water molecules. According to Meyer, the device required less energy to perform electrolysis than the minimum energy requirement predicted or measured by conventional science. If the device worked as specified, it would violate both the first and second laws of thermodynamics, allowing operation as a perpetual motion machine. Meyer's claims about his "Water Fuel Cell" and the car that it powered were found to be fraudulent by an Ohio court in 1996.
Throughout his patents and marketing material, Meyer uses the terms "fuel cell" or "water fuel cell" to refer to the portion of his device in which electricity is passed through water to produce hydrogen and oxygen. Meyer's use of the term in this sense is contrary to its usual meaning in science and engineering, in which such cells are
A Cape Island style fishing boat is an inshore motor fishing boat found across Atlantic Canada having a single keeled flat bottom at the stern and more rounded towards the bow. A Cape Island style boat is famous for its large step up to the bow.
It originated on Cape Sable Island, Nova Scotia about 1905. (Various online sources cite years 1905, 1906, and 1907.) Two families claim credit for its invention. The design is most commonly credited to Ephraim Atkinson of Clark's Harbour, Nova Scotia. The Atkinson family builders have continued building the world-renowned and recognized pleasure and commercial boats to this day.
The other claim to the boat's design is an accomplished boat-builder from Clark's Harbour, William A. Kenney, who is said to have constructed the first Cape Islander entirely from wood in 1905.
This boat can now be seen in use all over coastal Nova Scotia, North America, and the world. It is closely related to the Maine lobster boat.
The Analytical Engine was a proposed mechanical general-purpose computer designed by English mathematician Charles Babbage.
It was first described in 1837 as the successor to Babbage's Difference Engine, a design for a mechanical computer. The Analytical Engine incorporated an arithmetic logic unit, control flow in the form of conditional branching and loops, and integrated memory, making it the first design for a general-purpose computer that could be described in modern terms as Turing-complete.
Babbage was never able to complete construction of any of his machines due to conflicts with his chief engineer and inadequate funding. It was not until the 1940s that the first general-purpose computers were actually built.
Babbage's first attempt at a mechanical computing device, the Difference Engine, was a special-purpose calculator designed to tabulate logarithms and trigonometric functions by evaluating finite differences to create approximating polynomials. Construction of this machine was never completed; Babbage had conflicts with his chief engineer, Joseph Clement, and ultimately the British government withdrew its funding for the project.
During this project he realized that a
A Eunicycle is a computer controlled, partially self-balancing, motorized unicycle invented by Trevor Blackwell. It uses a computer control system similar to the one used by the Segway HT that servos its wheel to balance itself by keeping the contact point of the wheel below the center of mass of the vehicle in the front-to-back direction. To balance from side to side, the rider must rotate the vehicle the same way a unicyclist does, enabling the balancing servo to balance in the new direction.
The Eunicycle is based on an open design; the engineering drawings and control software source code are available from the website.
The Fairlight CMI (Computer Musical Instrument) is a digital sampling synthesizer. It was designed in 1979 by the founders of Fairlight, Peter Vogel and Kim Ryrie, and based on a dual-6800 microprocessor computer designed by Tony Furse in Sydney, Australia. It rose to prominence in the early 1980s and competed in the market with the Synclavier from New England Digital.
The Fairlight CMI was a development of an earlier synthesizer called the Qasar M8, an attempt to create sound by modeling all of the parameters of a waveform in real time. Unfortunately, this was beyond the available processing power of the day, and the results were disappointing. In an attempt to make something of it, Vogel and Ryrie decided to see what it would do with a naturally recorded sound wave as a starting point. To their surprise the effect was remarkable, and the digital sampler was born. In casting about for a name, Ryrie and Vogel settled upon Fairlight, the name of a hydrofoil (named in turn after Fairlight, New South Wales) that sped each day past Ryrie's grandmother's large house in Point Piper, New South Wales, underneath which Ryrie had a workroom.
By 1979, the Fairlight CMI Series I was being
A foghorn or fog signal or fog bell is a device that uses sound to warn vehicles of hazards or boats of the presence of other vehicles in foggy conditions. The term is most often used in relation to marine transport. When visual navigation aids such as lighthouses are obscured, foghorns provide an audible warning of rocks, shoals, headlands, or other dangers to shipping.
Audible fog signals have been used in one form or another for hundreds of years, initially simply bells or gongs struck manually.
At some lighthouses, a small cannon was let off periodically to warn away ships, but this had the obvious disadvantage of having to be fired manually throughout the whole period the fog persisted (which could be for several days). In the United States, whistles were also used where a source of steam power was available, though Trinity House, the British lighthouse authority, did not employ them, preferring an explosive signal.
Throughout the 19th century efforts were made to automate the signalling process. Trinity House eventually developed a system (the "Signal, Fog, Mk I") for firing a gun-cotton charge electrically. However, the charge had to be manually replaced after each signal.
Majorelle Blue is a clear, intense, fresh blue.
In 1924 the French artist Jacques Majorelle constructed his largest art work, the Majorelle Garden in Marrakech, Morocco, and painted the garden walls, fountains, features and villa this very intense shade of blue, for which he trademarked the name Majorelle Blue. He had noticed the colour in Moroccan tiles, in Berber burnouses, and around the windows of buildings such as kasbahs and native adobe homes.
The pantelegraph (Italian: pantelegrafo; French: pantélégraphe) was an early form of facsimile machine transmitting over normal telegraph lines developed by Giovanni Caselli, used commercially in the 1860s, that was the first such device to enter practical service, It could transmit handwriting, signatures, or drawings within an area of up to 150 x 100mm.
The Pantelegraph used a regulating clock with a pendulum which made and broke the current for magnetizing its regulators, and ensured that the transmitter's scanning stylus and the receiver's writing stylus remained in step. To provide a time base, a large pendulum was used weighing 8 kg (18 lb), mounted on a frame 2 m (6 ft 7 in) high. Two messages were written with insulating ink on two fixed metal plates; one plate was scanned as the pendulum moved to the right and the other as the pendulum moved to the left, so that two messages could be transmitted per cycle. The receiving apparatus reproduced the transmitted image by means of paper impregnated with potassium ferricyanide, which darkened when an electric current passed through it from the synchronized stylus. In operation the Pantelegraph was relatively slow; a sheet of paper
The Sinclair Executive was Clive Sinclair's first venture into the pocket calculator market. The Executive was the world's first "slimline" pocket calculator. It was variously described as "a piece of personal jewelry" (New Scientist) and "at once a conversation piece, a rich man's plaything and a functional business machine" (Design Magazine). An example of the calculator is displayed at the Museum of Modern Art in New York.
The Executive was launched in August 1972 at the price of GB£79.95 plus VAT. The average annual nominal earnings at the time was GB£1351, or about GB£26 per week.
The Executive weighed only 2.5 ounces (71 g) and measured 5.5 × 2.25 × 0.4 inches (14 × 5.7 × 1.0 cm).
The Executive was remarkably thin for its time, made possible by the first use of button-type batteries to power a calculator. To do this, Sinclair had to overcome the problem of the power hungry calculator electronics and light-emitting diode (LED) display. It was common to pulse the power to the LED display to reduce power consumption, but Sinclair's engineers found that it was also possible to rapidly pulse the main calculator integrated circuit (chip). This method of operation relied on the
DNA computing is a form of computing which uses DNA, biochemistry and molecular biology, instead of the traditional silicon-based computer technologies. DNA computing, or, more generally, biomolecular computing, is a fast developing interdisciplinary area. Research and development in this area concerns theory, experiments, and applications of DNA computing.
This field was initially developed by Leonard Adleman of the University of Southern California, in 1994. Adleman demonstrated a proof-of-concept use of DNA as a form of computation which solved the seven-point Hamiltonian path problem. Since the initial Adleman experiments, advances have been made and various Turing machines have been proven to be constructible.
While the initial interest was in using this novel approach to tackle NP-hard problems, it was soon realized that they may not be best suited for this type of computation, and several proposals have been made to find a "killer application" for this approach. In 1997 computer scientist Mitsunori Ogihara working with biologist Animesh Ray suggested one to be the evaluation of Boolean circuits and described an implementation.
In 2002, researchers from the Weizmann Institute
In measurement, the Coggeshall slide rule, also called a carpenter's slide rule, was a slide rule designed by Henry Coggeshall in 1677 to facilitate measuring the dimensions, superficies, and solidity of timber. With his original design and later improvements, Coggeshall's slide rule brought the tool its first practical use outside of mathematical study. It would remain popular for the next few centuries.
It consisted of two rulers, each a foot (30 cm) long, which were framed, or put together, in various ways. Sometimes, they were made to slide by one another; sometimes, a groove was made in the side of a common two-foot joint-rule, and a thin sliding piece was inserted, with Coggeshall's lines added on that side; but the most usual and handy way, was to have one of the rulers slide along a groove made along the middle of the other, as shown in the figure below.
Coggeshall first described this apparatus in a paper he released in London titled, "Timber-measure by a line of more ease, dispatch and exactness, then any other way now in use, by a double scale : after the countrey-measure, by the length and quarter of the circumference in round timber, and by the length and side of the
Driza-Bone, originating from the phrase "dry as a bone", is a trade name for the company making full-length waterproof riding coats and apparel. The company was established in 1898 and is currently Australian owned and manufactures its products in Australia. The trademark of Driza-Bone was first registered in 1933.
This style of coat originated in Australia as workwear for stockmen. The coats were developed to protect horse riders from the rain and feature straps that hold the coat to the rider's leg.
In the late 1800s, a Scot named Edward Le Roy emigrated to New Zealand. He was able to manufacture oilskin rainwear for use by sailors on sailing ships in the local waters at the time. The garments were originally constructed from the lightweight sails of the sailing ships. The waterproofing of the clothing was by application of linseed oil to the cotton. T. E. Pearson, the son of E. J. Pearson who started Pearson Soap in Hamilton, New Zealand, took a consignment of Leroy Coats to Australia. Stockmen at the time had gathered news of this garment from sailors who had subsequently left sailing to work on the land. Because the garments were flammable around campfires, T. E. Pearson
The Fresno Scraper is a machine used for constructing canals and ditches in sandy soil.
It was invented in 1883 by James Porteous. Working with farmers in Fresno, California, USA he had recognised the dependence of the Central San Joaquin Valley on irrigation, and the need for a more efficient means of constructing canals and ditches in the sandy soil. In perfecting the design of his machine, Porteous made several revisions on his own and also traded ideas with William Deidrick, Frank Dusy, and Abijah McCall, who invented and held patents on similar scrapers. Porteous bought the patents held by Deidrick, Dusy, and McCall, gaining sole rights to the Fresno Scraper.
The design of the Fresno Scraper forms the basis of most modern earthmoving scrapers, having the ability to scrape and move a quantity of soil, and also to discharge it at a controlled depth, thus quadrupling the volume which could be handled manually.
Prior scrapers pushed the soil ahead of them, while the Fresno scraper lifted it into a C-shaped bowl where it could be dragged along with much less friction. By lifting the handle, the operator could cause the scraper to bite deeper. Once soil was gathered, the handle
Zeta was the original name for General Motors' full-size rear-wheel drive automobile platform. The architecture was engineered by Holden of Australia and was most recently referred to as the "Global RWD Architecture". The GM Zeta replaced the Australian V-body and was considered as the replacement for the North American W, H, and K platforms, but ultimately not used. Although the future of the Zeta program was in doubt during GM's financial troubles, as of May 21, 2009, development of a new form of the Zeta chassis, said to be lighter and more economical has begun, intended to replace existing Australian-produced models. The Chevrolet Camaro is the only Zeta platform model to go into production in North America (Canada). All other Zeta platform vehicles are manufactured in Australia by Holden.
Development was started in late 1999 by Holden of Australia in order to replace the aging V-body platform underpinning their Commodore VT-VZ platform after sister division Opel announced that the Opel Omega (on which the Commodore was based) would be discontinued. Principal development on the VE Commodore was completed by July 2004 at a cost approaching A$1 billion and the first testing
The Internet Protocol (IP) is the principal communications protocol used for relaying datagrams (also known as network packets) across an internetwork using the Internet Protocol Suite responsible for routing packets across network boundaries. It is the primary protocol that establishes the Internet.
IP is the primary protocol in the Internet Layer of the Internet Protocol Suite and has the task of delivering datagrams from the source host to the destination host solely based on the addresses. For this purpose, IP defines datagram structures that encapsulate the data to be delivered. It also defines addressing methods that are used to label the datagram source and destination.
Historically, IP was the connectionless datagram service in the original Transmission Control Program introduced by Vint Cerf and Bob Kahn in 1974, the other being the connection-oriented Transmission Control Protocol (TCP). The Internet Protocol Suite is therefore often referred to as TCP/IP.
The first major version of IP, Internet Protocol Version 4 (IPv4), is the dominant protocol of the internet. Its successor is Internet Protocol Version 6 (IPv6), which is increasing in use.
The Internet Protocol is
The phonograph, record player, or gramophone (from the Greek: γράμμα, gramma, "letter" and φωνή, phōnē, "voice"), is a device introduced in 1877 for the recording and reproduction of sound recordings. The recordings played on such a device generally consist of wavy lines that are either scratched, engraved, or grooved onto a rotating cylinder or disc. As the cylinder or disc rotates, a stylus or needle traces the wavy lines and vibrates to reproduce the recorded sound waves.
The phonograph was invented in 1877 by Thomas Edison. While other inventors had produced devices that could record sounds, Edison's phonograph was the first to be able to reproduce the recorded sound. His phonograph originally recorded sound onto a tinfoil sheet phonograph cylinder, and could both record and reproduce sounds. Alexander Graham Bell's Volta Laboratory made several improvements in the 1880s, including the use of wax-coated cardboard cylinders, and a cutting stylus that moved from side to side in a "zig zag" pattern across the record. At the turn of the 19th century, Emile Berliner initiated the transition from phonograph cylinders to gramophone records: flat, double-sided discs with a spiral
Simunition is a trademark for training ammunition produced by General Dynamics - Ordnance and Tactical Systems Canada Inc. of Québec, Canada. Simunition encompasses many types of training rounds, the best-known being the FX Marking Cartridge.
Simunition rounds are designed to be fired through police and military service weapons. Most Simunition cartridges require slight modification to the weapon to ensure that normal service rounds cannot be fired during training and to simulate full recoil with reduced-pressure/reduced-velocity rounds for more realistic training.
SNC Technologies Inc. (now known as General Dynamics - Ordnance and Tactical Systems Canada Inc.) created Simunition in the late 1980s with the goal of providing more realistic training to military and law enforcement agencies.
FX marking cartridges are a line of training ammunition that can be fired through standard firearms. The cartridges come in 9mm/.38 and 5.56mm calibers and fire using a special pressurized gas system for a reduced velocity. The projectile is filled with a detergent-based, water-soluble colored marking compound, similar to a paintball. The projectile breaks upon impact, marking the target and
A siren is a loud noise making device. Most modern ones are civil defense or air raid sirens, tornado sirens, nuclear test sirens, or the sirens on emergency service vehicles such as ambulances, police cars and fire trucks. There are two general types: pneumatic and electronic.
Many fire sirens serve double duty as tornado or civil defense sirens, alerting an entire community of impending danger. Most fire sirens are either mounted on the roof of a fire station, or on a pole next to the fire station. Fire sirens can also be mounted near government buildings, on tall structures such as water towers, as well as in systems, where several sirens are distributed around a town for better sound coverage. Most fire sirens are single tone and mechanically driven by electric motors with a rotor attached to the shaft. Some newer sirens are electronically driven by speakers, though these are not as common. Fire sirens are often called "fire whistles", "fire alarms", "fire horns." Although there is no standard signaling of fire sirens, some utilize codes to inform firefighters to the location of the fire. Civil defense sirens pulling double duty as a fire siren often can produce an alternating
Stephenson's Rocket was an early steam locomotive of 0-2-2 wheel arrangement, built in 1829 at the Forth Street Works of Robert Stephenson and Company in Newcastle Upon Tyne.
It was built for, and won, the Rainhill Trials held by the Liverpool & Manchester Railway in 1829 to choose the best design to power the railway.
Though the Rocket was not the first steam locomotive, it was the first to bring together several innovations to produce the most advanced locomotive of its day.
It is the most famous example of an evolving design of locomotives by Stephenson that became the template for most steam engines in the following 150 years.
The locomotive had a tall smokestack chimney at the front, a cylindrical boiler in the middle, and a separate firebox at the rear. The large front pair of wooden wheels were driven by two external cylinders set at an angle. The smaller rear wheels were not coupled to the driving wheels, giving an 0-2-2 wheel arrangement.
Stephenson designed Rocket for the Rainhill trials, and the specific rules of that contest. As the first railway intended for passengers more than freight, the rules emphasised speed and would require reliability, but the weight of the
A Stirling engine is a heat engine operating by cyclic compression and expansion of air or other gas, the working fluid, at different temperature levels such that there is a net conversion of heat energy to mechanical work. Or more specifically, a closed-cycle regenerative heat engine with a permanently gaseous working fluid, where closed-cycle is defined as a thermodynamic system in which the working fluid is permanently contained within the system, and regenerative describes the use of a specific type of internal heat exchanger and thermal store, known as the regenerator. It is the inclusion of a regenerator that differentiates the Stirling engine from other closed cycle hot air engines.
Originally conceived in 1816 as an industrial prime mover to rival the steam engine, its practical use was largely confined to low-power domestic applications for over a century.
The Stirling engine is noted for its high efficiency compared to steam engines, quiet operation, and the ease with which it can use almost any heat source. This compatibility with alternative and renewable energy sources has become increasingly significant as the price of conventional fuels rises, and also in light of
Television (TV) is a telecommunication medium for transmitting and receiving moving images that can be monochrome (black-and-white) or colored, with or without accompanying sound. "Television" may also refer specifically to a television set, television programming, or television transmission.
The etymology of the word has a mixed Latin and Greek origin, meaning "far sight": Greek tele (τῆλε), far, and Latin visio, sight (from video, vis- to see, or to view in the first person).
Commercially available since the late 1920s, the television set has become commonplace in homes, businesses and institutions, particularly as a vehicle for advertising, a source of entertainment, and news. Since the 1950s, television has been the main medium for molding public opinion. Since the 1970s the availability of video cassettes, laserdiscs, DVDs and now Blu-ray Discs, have resulted in the television set frequently being used for viewing recorded as well as broadcast material. In recent years Internet television has seen the rise of television available via the Internet, e.g. iPlayer and Hulu.
Although other forms such as closed-circuit television (CCTV) are in use, the most common usage of the
Aerosol spray is a type of dispensing system which creates an aerosol mist of liquid particles. This is used with a can or bottle that contains a liquid under pressure. When the container's valve is opened, the liquid is forced out of a small hole and emerges as an aerosol or mist. As gas expands to drive out the payload, only some propellant evaporates inside the can to maintain an even pressure. Outside the can, the droplets of propellant evaporate rapidly, leaving the payload suspended as very fine particles or droplets. Typical liquids dispensed in this way are insecticides, deodorants and paints. An atomizer is a similar device that is pressurised by a hand-operated pump rather than by stored gas.
The concepts of aerosol probably goes as far back as 1790. The first aerosol spray can patent was granted in Oslo in 1926 to Erik Rotheim, a Norwegian chemical engineer, and a United States patent was granted for the invention in 1931. The patent rights were sold to a United States company for 100,000 Norwegian kroner. The Norwegian Post Office celebrated the invention by issuing a stamp in 1998.
In 1939, American Julian S. Kahn received a patent for a disposable spray can, but the
An assembly line is a manufacturing process (most of the time called a progressive assembly) in which parts (usually interchangeable parts) are added to a product in a sequential manner to create a finished product much faster than with handcrafting-type methods. The division of labour was initially discussed by Adam Smith, regarding the manufacture of pins, in his book The Wealth of Nations (published in 1776). The assembly line was first mechanized in the U.S. by Eli Whitney, who also patented a type of cotton gin. Whitney began using the assembly line to manufacture muskets that had interchangeable parts. In 1797, he was contracted to supply 10,000 muskets for the U.S. government in two years. Prior to Whtiney's mechanization of the assembly line, craftsmen would hand make one musket at a time. Therefore, each musket was unique. If a single part of the musket broke it could not be easily replaced. Because parts manufactured by Whitney's assembly line parts were interchangeable. In the early 1900s, Ford Motor Company adopted the assembly line to mass produce the Model T.
Assembly lines are designed for the sequential organization of workers, tools or machines, and parts. The
Lithium batteries are disposable (primary) batteries that have lithium metal or lithium compounds as an anode. They stand apart from other batteries in their high charge density (long life) and high cost per unit. Depending on the design and chemical compounds used, lithium cells can produce voltages from 1.5 V (same as zinc–carbon battery or alkaline battery) to about 3.7 V. Lithium batteries are widely used in products such as portable consumer electronic devices.
Lithium primary batteries account for 28% of all primary battery sales in Japan but only 1% of all battery sales in Switzerland. In the UK and EU only 0.5% of all battery sales including secondary types are lithium primaries.
The term "lithium battery" refers to a family of different chemistries, comprising many types of cathodes and electrolytes.
The most common type of lithium cell used in consumer applications uses metallic lithium as anode and manganese dioxide as cathode, with a salt of lithium dissolved in an organic solvent.
Another type of lithium cell having a large energy density is the lithium-thionyl chloride cell. Lithium-thionyl chloride batteries are generally not sold to the consumer market, and find
Napier's bones is an abacus created by John Napier for calculation of products and quotients of numbers that was based on Arab mathematics and lattice multiplication used by Matrakci Nasuh in the Umdet-ul Hisab and Fibonacci writing in the Liber Abaci. Also called Rabdology (from Greek ῥάβδoς [r(h)abdos], "rod" and -λογία [logia], "study"). Napier published his version of rods in a work printed in Edinburgh, Scotland, at the end of 1617 entitled Rabdologiæ. Using the multiplication tables embedded in the rods, multiplication can be reduced to addition operations and division to subtractions. More advanced use of the rods can even extract square roots. Note that Napier's bones are not the same as logarithms, with which Napier's name is also associated.
The abacus consists of a board with a rim; the user places Napier's rods in the rim to conduct multiplication or division. The board's left edge is divided into 9 squares, holding the numbers 1 to 9. The Napier's rods consist of strips of wood, metal or heavy cardboard. Napier's bones are three dimensional, square in cross section, with four different rods engraved on each one. A set of such bones might be enclosed in a convenient
Limelight (also known as calcium light) is a type of stage lighting once used in theatres and music halls. An intense illumination is created when an oxyhydrogen flame is directed at a cylinder of quicklime (calcium oxide), which can be heated to 2572 °C before melting. The light is produced by a combination of incandescence and candoluminescence. Although it has long since been replaced by electric lighting, the term has nonetheless survived, as someone in the public eye is still said to be “in the limelight.” The actual lights are called limes, a term which has been transferred to electrical equivalents.
The limelight effect was discovered in the 1820s by Goldsworthy Gurney, based on his work with the "oxy-hydrogen blowpipe," credit for which is normally given to Robert Hare. In 1825, a Scottish engineer, Thomas Drummond (1797–1840), saw a demonstration of the effect by Michael Faraday and realized that the light would be useful for surveying. Drummond built a working version in 1826, and the device is sometimes called the Drummond Light after him.
Limelight was first used in public in the Covent Garden Theatre in London in 1837 and enjoyed widespread use in theatres around the
A partial cloverleaf interchange or parclo is a modification of a cloverleaf interchange. The parclo interchange was developed by the Ontario Ministry of Transportation as a replacement for the cloverleaf on 400-Series Highways, removing the dangerous weaving patterns and allowing for more acceleration and deceleration space on the freeway. The design has been well received, and has since become one of the most popular freeway-to-arterial interchange designs in North America. It has also been used occasionally in some European countries, such as Germany, the Netherlands, and the United Kingdom.
In Ontario, the specific variation is identified by a letter/number suffix after the name. Other jurisdictions do not have naming conventions, so Ontario's naming conventions are used in this article. The letter A designates that two ramps meet the freeway before the driver crosses the arterial road, while B designates that two ramps meet the freeway past the crossing. The number designates how many quadrants of the interchange contain ramps. In left-hand drive countries, the ramps function the same as in right-hand drive countries, but ramps with the same designation appear visually
The aerial steam carriage, also named Ariel, was a flying machine patented in 1842 that was supposed to carry passengers into the air. It was, in practice, incapable of flight since it had insufficient power from its heavy steam engine to fly. A more successful model was built in 1848 which was able to fly for small distances within a hangar. The aerial steam carriage was significant because it was a transition from glider experimentation to powered flight experimentation.
The Ariel was to be a monoplane with a wing span of 150 feet (46 m), weigh 3,000 lb (1,400 kg) and was to be powered by a specially-designed lightweight steam powered engine producing 50 hp (37 kW). The wing area was to be 4,500 sq ft (420 m)., with the tail another 1500, yielding a very low wing loading. The inventors hoped that the Ariel would achieve a speed of 50 mph, and carry 10–12 passengers up to 1,000 miles (1,600 km). The plan was to launch it from an inclined ramp. The undercarriage was a 3-wheel design.
William Samuel Henson (1812–1888) and John Stringfellow (1799–1883) received British patent 9478 in 1842.
In order that the description hereafter given be rendered clear, I will first shortly explain
Balloon mail refers to the transport of mail (usually for weight reasons in the form of a postcard) carrying the name of the sender by means of an unguided hydrogen or helium filled balloon. Since the balloon is not controllable, the delivery of a balloon mail is left to good fortune; often the balloon and postcard are lost. A found balloon should be returned to the sender (by conventional post) with an indication of the discovery site, so that the sender can determine how far their balloon flew. Frequently balloon mail is sent as part of a balloon competition.
Historically, balloons were used to transport mail from Paris during the Franco-Prussian War of 1870-72. Sixty-five unguided mail balloons were released in besieged Paris to communicate with the world beyond the besieging forces, of which only two went missing. The world’s first balloon airmail service was begun out of pure necessity and carried out by the brave acts and audacity of some of France’s greatest scientists, inventors and artists. From the first announcement of the impending arrival of Prussian uhlans at the city gates, Parisians refused to capitulate. Instead, the city rallied around the formation of a new
Harris Tweed (Clò Mór or Clò na Hearadh in Gaelic) is a cloth that has been handwoven by the islanders on the Isles of Harris, Lewis, Uist and Barra in the Outer Hebrides of Scotland, using local wool.
Traditional Harris Tweed was characterized by subtle flecks of colour achieved through the use of vegetable dyes, including the lichen dyes called "crottle" (Parmelia saxatilis and Parmelia omphalodes which give deep red- or purple-brown and rusty orange respectively). These lichens are the origin of the distinctive scent of older Harris Tweed.
The original name of the cloth was tweel, Scots for twill, it being woven in a twilled rather than a plain pattern. A traditional story has the name coming about almost by chance. About 1830, a London merchant received a letter from a Hawick firm about some tweels. The London merchant misinterpreted the handwriting, understanding it to be a trade-name taken from the river Tweed that flows through the Scottish Borders textile area. Subsequently the goods were advertised as Tweed, and the name has remained ever since.
During the economic difficulties of the Highland potato famine of 1846-7, Catherine Murray, Countess of Dunmore was instrumental
Charles G. Hutchinson invented and patented the Hutchinson Patent Stopper in 1879 as a replacement for cork bottle stoppers which were commonly being used as stoppers on soda water or pop bottles. His invention employed a wire spring attached to a rubber seal. Production of these stoppers was discontinued in 1912.
Penicillin (sometimes abbreviated PCN or pen) is a group of antibiotics derived from Penicillium fungi. They include penicillin G, procaine penicillin, benzathine penicillin, and penicillin V. Penicillin antibiotics are historically significant because they are the first drugs that were effective against many previously serious diseases, such as syphilis, and infections caused by staphylococci and streptococci. Penicillins are still widely used today, though many types of bacteria are now resistant. All penicillins are β-lactam antibiotics and are used in the treatment of bacterial infections caused by susceptible, usually Gram-positive, organisms.
The term "penicillin" is often used generically to refer to benzylpenicillin (penicillin G), procaine benzylpenicillin (procaine penicillin), benzathine benzylpenicillin (benzathine penicillin), and phenoxymethylpenicillin (penicillin V).
Procaine penicillin and benzathine penicillin have the same antibacterial activity as benzylpenicillin but act for a longer time span. Phenoxymethylpenicillin is less active against Gram-negative bacteria than benzylpenicillin. Benzylpenicillin, procaine penicillin and benzathine penicillin are given by
The Playfair cipher or Playfair square is a manual symmetric encryption technique and was the first literal digraph substitution cipher. The scheme was invented in 1854 by Charles Wheatstone, but bears the name of Lord Playfair who promoted the use of the cipher.
The technique encrypts pairs of letters (digraphs), instead of single letters as in the simple substitution cipher and rather more complex Vigenère cipher systems then in use. The Playfair is thus significantly harder to break since the frequency analysis used for simple substitution ciphers does not work with it. Frequency analysis can still be undertaken, but on the 600 possible digraphs rather than the 26 possible monographs. The frequency analysis of digraphs is possible, but considerably more difficult – and it generally requires a much larger ciphertext in order to be useful.
Despite its invention by Wheatstone, it became known as the Playfair cipher after Lord Playfair, who heavily promoted its use. The first recorded description of the Playfair cipher was in a document signed by Wheatstone on 26 March 1854.
It was rejected by the British Foreign Office when it was developed because of its perceived complexity. When
Sans Pareil is a steam locomotive built by Timothy Hackworth which took part in the 1829 Rainhill Trials on the Liverpool and Manchester Railway, held to select a builder of locomotives. The name means, roughly, 'Without equal' in French.
While a capable locomotive for the day, its technology was somewhat antiquated compared to George and Robert Stephenson's Rocket, the winner of the Rainhill Trials and the £500 prize money. Instead of the fire tube boiler of Rocket, Sans Pareil had a double return flue. To increase the heating surface area, the two flues were joined by a U shaped tube at the forward end of the boiler; the firebox and chimney were both positioned at the rear same end, one on either side.
Sans Pareil had two cylinders, mounted vertically at the opposite end to the chimney, and driving one pair of driving wheels directly - the other pair were driven via connecting rods, in the typical steam locomotive fashion.
At the Rainhill Trials, Sans Pareil was excluded from the prize because it was slightly over the maximum permitted weight. Nevertheless it performed very well but had a strange rolling gait due to its vertical cylinders. The 'blast' from the blastpipe was, in
A snow blower or snow thrower is a machine for removing snow from an area where it is not wanted, such as a driveway, sidewalk, roadway, railroad track, rink, runway, or houses. The term "snow thrower" is often used to encompass snow throwers and snow blowers, however, in proper a snow thrower is a machine that uses a single stage to remove or "throw" snow while a snowblower uses two stages to remove or "blow" snow. It can use either electric power, or a gasoline or diesel engine to throw snow to another location or into a truck to be hauled away. This is in contrast with the action of snow plows, which push snow to the front or side (shovels can be similarly used).
Snow throwers range from the very small, capable of removing only a few inches (a few cm) of light snow in an 18 to 20 in (457 to 508 mm) path, to the very large, mounted onto heavy duty winter service vehicles and capable of moving 10-foot (3.05 m) wide, or wider, swaths of heavy snow up to 6 feet (1.83 m) deep. Snow blowers can generally be divided into two classes: single stage and two stage.
Single-stage snow throwers use a single high-speed impeller to both move the snow into the machine and force it out of the
The Winged Keel is a sailboat keel originally designed by Ben Lexcen and made its first appearance on the 12-metre class yacht Australia II in the 1983 America's Cup. Along with Australia II's efficient sail design, this keel was one of the factors contributing to Australia II's success. The increased stability afforded by the winged keel, due mainly to the extra lead in the wings producing a very low centre of gravity, allowed Australia II to be as short and light as possible under the 12 meter rules, and still carry enough sail to beat the American entry. The wings were angled downwards at about 20 degrees, which, since they were lifting downwards, acted as a dihedral.
The lateral wings of a winged keel are usually of moderate aspect ratio, that uses a nearly horizontal foil, the "wing", at the bottom to provide additional span. Note that, contrary to classic configuration, the keel is "upside down" under the hull (the root chord is smaller than the tip (bottom) chord. Each wing acts as a winglet, effectively doubling the keel aspect ratio and reducing lift-induced drag. Because the yacht is heeled over when sailing upwind the leeward foil is closer to vertical and provides
A bouncing bomb is a bomb designed specifically to bounce to a target across water in a calculated manner to avoid obstacles such as torpedo nets, and to allow both the bomb's speed on arrival at the target and the timing of its detonation to be pre-determined, in a similar fashion to a regular naval depth charge. The inventor of the first such bomb was the British engineer Barnes Wallis, whose "Upkeep" bouncing bomb was used in the RAF's Operation Chastise of May 1943 to bounce into German dams and explode underwater, with effect similar to the underground detonation of the earthquake bombs Grand Slam and Tallboy, both of which he also invented.
Barnes Wallis's April 1942 paper "Spherical Bomb — Surface Torpedo" described a method of attack in which a weapon would be bounced across water until it struck its target, then sinking to explode underwater, much like a depth charge. Bouncing it across the surface would allow it to be aimed directly at its target, while avoiding underwater defences, as well as some above the surface, and such a weapon would take advantage of the "bubble pulse" effect typical of underwater explosions, greatly increasing its effectiveness: Wallis's paper
A box wine (or boxed wine, goon, cask wine) is a wine packaged as a bag-in-box. Such packages contain a plastic bladder protected by a box, usually made of corrugated fiberboard.
The process for packaging 'cask wine' (box wine) was invented by Thomas Angove of Angove's, a winemaker from Renmark, South Australia, and patented by the company on April 20, 1965. Polyethelene bladders of 1 gallon (3.78 litres) were placed in corrugated boxes for retail sale. The original design required that the consumer cut the corner off the bladder, pour out the serving of wine and then reseal it with a special peg.
In 1967 Charles Henry Malpas and Penfolds Wines patented a plastic, air-tight tap welded to a metallised bladder, making storage more convenient. All modern wine casks now use some sort of plastic tap, which is exposed by tearing away a perforated panel on the box.
Bag in a box packaging is also preferred by producers of less expensive wines because it is cheaper than glass bottles.
The packaging first found commercial success in the land of its invention, Australia, and has since established a steady market across Europe and South Africa. However, boxed wine has found difficulty in
A windup radio or clockwork radio is a radio that is powered by human muscle power rather than batteries or the electrical grid. In the most common arrangement, an internal electrical generator is run by a mainspring, which is wound by a hand crank on the case. Turning the crank winds the spring and a full winding will allow several hours of operation. Alternatively, the generator can charge an internal battery.
Like other self-powered equipment, windup radios were intended for camping, emergencies and for use in areas of the world where there is no electrical grid and replacement batteries are hard to obtain, such as in developing countries or remote settlements. They are also useful where a radio is not used on a regular basis and batteries would deteriorate, such as at a vacation house or cabin.
Windup radios designed for emergency use often included flashlights, blinking emergency lights, and emergency sirens. They also may include multiple alternate power sources such as disposable or rechargeable batteries, auto cigarette lighter plugs, and solar cells.
Radios powered by handcranked generators are not new, but their market was previously seen as limited to emergency or
In electricity generation, an electric generator is a device that converts mechanical energy to electrical energy. A generator forces electric charge (usually carried by electrons) to flow through an external electrical circuit. The source of mechanical energy may be a reciprocating or turbine steam engine, water falling through a turbine or waterwheel, an internal combustion engine, a wind turbine, a hand crank, compressed air, or any other source of mechanical energy.
The reverse conversion of electrical energy into mechanical energy is done by an electric motor, and motors and generators have many similarities. Many motors can be mechanically driven to generate electricity and frequently make acceptable generators.
Before the connection between magnetism and electricity was discovered, electrostatic generators were used. They operated on electrostatic principles. Such generators generated very high voltage and low current. They operated by using moving electrically charged belts, plates, and disks that carried charge to a high potential electrode. The charge was generated using either of two mechanisms:
Because of their inefficiency and the difficulty of insulating machines that
A linear motor is an electric motor that has had its stator and rotor "unrolled" so that instead of producing a torque (rotation) it produces a linear force along its length. The most common mode of operation is as a Lorentz-type actuator, in which the applied force is linearly proportional to the current and the magnetic field .
Many designs have been put forward for linear motors, falling into two major categories, low-acceleration and high-acceleration linear motors. Low-acceleration linear motors are suitable for maglev trains and other ground-based transportation applications. High-acceleration linear motors are normally rather short, and are designed to accelerate an object to a very high speed, for example see the railgun.
They are usually used for studies of hypervelocity collisions, as weapons, or as mass drivers for spacecraft propulsion. The high-acceleration motors are usually of the AC linear induction motor (LIM) design with an active three-phase winding on one side of the air-gap and a passive conductor plate on the other side. However, the direct current homopolar linear motor railgun is another high acceleration linear motor design. The low-acceleration, high speed
The logarithm of a number is the exponent by which another fixed value, the base, has to be raised to produce that number. For example, the logarithm of 1000 to base 10 is 3, because 1000 is 10 to the power 3: 1000 = 10 × 10 × 10 = 10. More generally, if x = b, then y is the logarithm of x to base b, and is written y = logb(x), so log10(1000) = 3.
Logarithms were introduced by John Napier in the early 17th century as a means to simplify calculations. They were rapidly adopted by navigators, scientists, engineers, and others to perform computations more easily, using slide rules and logarithm tables. Tedious multi-digit multiplication steps can be replaced by table look-ups and simpler addition because of the fact — important in its own right — that the logarithm of a product is the sum of the logarithms of the factors:
The present-day notion of logarithms comes from Leonhard Euler, who connected them to the exponential function in the 18th century.
The logarithm to base b = 10 is called the common logarithm and has many applications in science and engineering. The natural logarithm has the constant e (≈ 2.718) as its base; its use is widespread in pure mathematics, especially
The south-pointing chariot (or carriage) was an ancient Chinese two-wheeled vehicle that carried a movable pointer to indicate the south, no matter how the chariot turned. Usually, the pointer took the form of a doll or figure with an outstretched arm. The chariot was supposedly used as a compass for navigation, and may also have had other purposes.
There are legends of earlier south-pointing chariots, but the first reliably documented one was created by Ma Jun (c. 200–265 CE) of Cao Wei during the Three Kingdoms, about eight hundred years before the first navigational use of a magnetic compass. No ancient chariots still exist, but many extant ancient Chinese texts mention them, saying they were used intermittently until about 1300 CE. Some include information about their inner components and workings.
There were probably several types of south-pointing chariot which worked differently. In most or all of them, the rotating road wheels mechanically operated a geared mechanism to keep the pointer aimed correctly. The mechanism had no magnets and did not automatically detect which direction was south. The pointer was aimed southward by hand at the start of a journey, then, whenever
Inventor:Edward Somerset, 2nd Marquess of Worcester
A steam engine is a heat engine that performs mechanical work using steam as its working fluid.
Steam engines are external combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be used. Water turns to steam in a boiler and reaches a high pressure. When expanded through pistons or turbines, mechanical work is done. The reduced-pressure steam is then released into the atmosphere or condensed and pumped back into the boiler. The ideal thermodynamic cycle used to analyze this process is called the Rankine cycle. Most mobile steam engines and some smaller stationary engines discard the low-pressure steam instead of condensing it for reuse.
The idea of using boiling water to produce mechanical motion has a very long history, going back about 2,000 years. Early devices were not practical power producers, but more advanced designs producing usable power have become a major source of mechanical power over the last 300 years, beginning with applications for removing water from mines using vacuum engines. Subsequent developments used pressurized steam and converted linear to
In computer science, a suffix tree (also called PAT tree or, in an earlier form, position tree) is a data structure that presents the suffixes of a given string in a way that allows for a particularly fast implementation of many important string operations.
The suffix tree for a string is a tree whose edges are labeled with strings, such that each suffix of corresponds to exactly one path from the tree's root to a leaf. It is thus a radix tree (more specifically, a Patricia tree) for the suffixes of .
Constructing such a tree for the string takes time and space linear in the length of . Once constructed, several operations can be performed quickly, for instance locating a substring in , locating a substring if a certain number of mistakes are allowed, locating matches for a regular expression pattern etc. Suffix trees also provided one of the first linear-time solutions for the longest common substring problem. These speedups come at a cost: storing a string's suffix tree typically requires significantly more space than storing the string itself.
The concept was first introduced as a position tree by Weiner (1973), which Donald Knuth subsequently characterized as "Algorithm of
The telephone, colloquially referred to as a phone, is a telecommunications device that transmits and receives sounds, usually the human voice. Telephones are a point-to-point communication system whose most basic function is to allow two people separated by large distances to talk to each other. Developed in the mid-1870s by Alexander Graham Bell and others, the telephone has long been considered indispensable to businesses, households and governments, is now one of the most common appliances in the developed world. The word "telephone" has been adapted to many languages and is now recognized around the world.
All modern telephones have a microphone to speak into, an earphone (or 'speaker') which reproduces the voice of the other person, a ringer which makes a sound to alert the owner when a call is coming in, and a keypad (or on older phones a telephone dial) to enter the telephone number of the telephone to be called. The microphone and earphone are usually built into a handset which is held up to the face to talk. The keypad may be part of the handset or of a base unit to which the handset would be connected. A landline telephone is connected by a pair of wires to the telephone
The tri-star is a novel wheel design—originally by Robert and John Forsyth, assignors to Lockheed in 1967—in which three wheels are arranged in an upright triangle with two on the ground and one above them. If either of the wheels in contact with the ground gets stuck, the whole system rotates over the obstruction. (Patent #3,348,518)
Its most famous application was the Landmaster, a unique armoured personnel carrier (APC) from the film Damnation Alley. Its common application is employed as a stairclimber.
Lockheed also modified an M2A2 105mm Light Howitzer from 1969-1977 with an drive unit and tri-star wheel system into an Auxiliary Propelled Howitzer they termed "Terra Star." The only surviving prototype is located at the Rock Island Arsenal Museum
A walkie-talkie (more formally known as a handheld transceiver) is a hand-held, portable, two-way radio transceiver. Its development during the Second World War has been variously credited to Donald L. Hings, radio engineer Alfred J. Gross, and engineering teams at Motorola. Similar designs were created for other armed forces, and after the war, walkie-talkies spread to public safety and eventually commercial and jobsite work. Major characteristics include a half-duplex channel (only one radio transmits at a time, though any number can listen) and a "push-to-talk" (PTT) switch that starts transmission. Typical walkie-talkies resemble a telephone handset, possibly slightly larger but still a single unit, with an antenna mounted on the top of the unit. Where a phone's earpiece is only loud enough to be heard by the user, a walkie-talkie's built-in speaker can be heard by the user and those in the user's immediate vicinity. Hand-held transceivers may be used to communicate between each other, or to vehicle-mounted or base stations.
The first radio receiver/transmitter to be widely nicknamed "Walkie-Talkie" was the backpacked Motorola SCR-300, created by an engineering team in 1940 at
Invented and developed by Richard Waters, a waterphone is a type of atonal acoustic musical instrument consisting of a stainless steel resonator bowl or pan with a cylindrical neck and bronze rods of different lengths and diameters around the rim of the bowl. The resonator may contain a small amount of water giving the waterphone a vibrant ethereal sound that has appeared in movie soundtracks, record albums, and live performances.
Several sizes and design variants of the instrument exist. It is generally played in a seated position by a soloist and either bowed or drummed with movements to affect the water inside. This creates the resonant characteristics of the bowl and rods in combination with the movement of the water. The sound of the waterphone is often used to evoke mystery and suspense. A superball mallet has become the prime way of playing the waterphone in a friction mode.
The waterphone is a modern invention related to the Tibetan Water Drum, a round, slightly flattened, bronze, drum with an aperture in the center top. According to the inventor of the waterphone, Richard A. Waters, the waterphone in part relates to this design as well as the nail violin, which also used a
An aerial tramway, cable car, ropeway (Japanese) or aerial tram is a type of aerial lift which uses one or two stationary ropes for support while a third moving rope provides propulsion. With this form of lift, the grip of an aerial tramway cabin is fixed onto the propulsion rope and cannot be decoupled from it during operations.
Because of the proliferation of such systems in the Alpine regions of Europe, the French and German language names of téléphérique and Seilbahn, respectively, are often also used in an English language context. Cable car is the usual term in British English, as in British English the word tramway generally refers to a railed street tramway while in American English, cable car is most often associated with a type of cable-pulled street tramway with detachable vehicles; e.g., San Francisco's cable cars. As such, careful phrasing is necessary to prevent confusion. It is also sometimes called a ropeway or even incorrectly referred to as a gondola lift. A gondola lift has cabins suspended from a continuously circulating cable whereas aerial trams simply shuttle back and forth on cables. In Japan, the two are considered as the same vehicle and called ropeway,
An aircraft is a vehicle that is able to fly by gaining support from the air, or, in general, the atmosphere of a planet. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines.
The human activity that surrounds aircraft is called aviation. Crewed aircraft are flown by an onboard pilot, but unmanned aerial vehicles may be remotely controlled or self-controlled by onboard computers. Aircraft may be classified by different criteria, such as lift type, propulsion, usage, and others.
Flying model craft and stories of manned flight go back many centuries, however the first manned ascent - and safe descent - in modern times took place by hot-air balloon in the 18th century. Each of the two World Wars led to great technical advances. Consequently the history of aircraft can be divided into five eras:
Aerostats use buoyancy to float in the air in much the same way that ships float on the water. They are characterized by one or more large gasbags or canopies, filled with a relatively low-density gas such as helium, hydrogen, or hot air, which is less dense than the surrounding air. When
Alkaline batteries are a type of primary batteries dependent upon the reaction between zinc and manganese dioxide (Zn/MnO2). A rechargeable alkaline battery allows reuse of specially designed cells.
Compared with zinc-carbon batteries of the Leclanché or zinc chloride types, alkaline batteries have a higher energy density and longer shelf-life, with the same voltage. Button cell silver-oxide batteries have higher energy density and capacity but also higher cost than similar-size alkaline cells.
The alkaline battery gets its name because it has an alkaline electrolyte of potassium hydroxide, instead of the acidic ammonium chloride or zinc chloride electrolyte of the zinc-carbon batteries. Other battery systems also use alkaline electrolytes, but they use different active materials for the electrodes.
Alkaline batteries account for 80% of manufactured batteries in the US and over 10 billion individual units produced worldwide. In Japan alkaline batteries account for 46% of all primary battery sales. In Switzerland alkaline batteries account for 68%, in the UK 60% and in the EU 47% of all battery sales including secondary types.
Alkaline batteries are used in many household items
Atomic absorption spectroscopy (AAS) is a spectroanalytical procedure for the quantitative determination of chemical elements employing the absorption of optical radiation (light) by free atoms in the gaseous state.
In analytical chemistry the technique is used for determining the concentration of a particular element (the analyte) in a sample to be analyzed. AAS can be used to determine over 70 different elements in solution or directly in solid samples employed in pharmacology, biophysics and toxicology research.
Atomic absorption spectrometry was first used as an analytical technique, and the underlying principles were established in the second half of the 19th century by Robert Wilhelm Bunsen and Gustav Robert Kirchhoff, both professors at the University of Heidelberg, Germany.
The modern form of AAS was largely developed during the 1950s by a team of Australian chemists. They were led by Sir Alan Walsh at the CSIRO (Commonwealth Scientific and Industrial Research Organization), Division of Chemical Physics, in Melbourne, Australia.
The technique makes use of absorption spectrometry to assess the concentration of an analyte in a sample. It requires standards with known analyte
George Stephenson built a number of experimental steam locomotives to work in the 'Killingworth Colliery' between 1814 and 1826.
George Stephenson was appointed as engine-wright at Killingwoth Colliery in 1812 and immediately improved the haulage of the coal from the mine using fixed engines. But he had taken an interest in Blenkinsop's engines in Leeds and Blackett's experiments at Wylam colliery, where he had been born. By 1814 he persuaded the lessees of the colliery to fund a "travelling engine" which first ran on 25 July. By experiment he confirmed Blackett's observation that the friction of the wheels was sufficient on an iron railway without cogs but still used a cogwheel system in transmitting power to the wheels.
Blücher (often spelled Blutcher) was built by George Stephenson in 1814; the first of a series of locomotives that he designed in the period 1814–16 which established his reputation as an engine designer and laid the foundations for his subsequent pivotal role in the development of the railways. It could pull a train of 30 tons at a speed of 4 mph up a gradient of 1 in 450. It was named after the Prussian general Gebhard Leberecht von Blücher, who, after a speedy
A Bowden cable ( /ˈboʊdən/ BOH-dən) is a type of flexible cable used to transmit mechanical force or energy by the movement of an inner cable (most commonly of steel or stainless steel) relative to a hollow outer cable housing. The housing is generally of composite construction, consisting of a helical steel wire, often lined with nylon, and with a plastic outer sheath.
The linear movement of the inner cable is most often used to transmit a pulling force, although push/pull cables have gained popularity in recent years e.g. as gear shift cables. Many light aircraft use a push/pull bowden cable for the throttle control, and here it is normal for the inner element to be solid wire, rather than a multi-strand cable. Usually provision is made for adjusting the cable tension using an inline hollow bolt (often called a "barrel adjuster"), which lengthens or shortens the cable housing relative to a fixed anchor point. Lengthening the housing (turning the barrel adjuster out) tightens the cable; shortening the housing (turning the barrel adjuster in) loosens the cable.
The origin and invention of the Bowden Cable is open to some dispute, confusion and popular myth.
The invention of the
The cam-in-block valvetrain layout of piston engines is one where the camshaft is placed within the cylinder block, usually beside and slightly above the crankshaft in a straight engine or directly above the crankshaft in the V of a V engine. This contrasts with an overhead camshaft (OHC) design which places the camshafts within the cylinder head and drives the valves directly or through short rocker arms.
Placing the camshaft inside the engine block has a long history in its use in valve-in-block engines, in straight and V configurations, the Ford flathead being exemplary of the type. Pushrod overhead valve engines with the cam in the block were long used in Chevrolet and Buick straight engines from the 1930s through the mid 1950s and in various similar six-cylinder engines until the extensive employment of the V6 configuration in the 1980s.
There are three main cam-in-block designs:
L-head (flathead) refers to the pushrod valvetrain configuration in which the valves are placed in the engine block beside the pistons. The design was common on early engine designs, but has since fallen from use.
Generally L-head engines use a small chamber on one side of the cylinder to carry the
The Coolgardie Safe is a low-tech refrigeration unit which uses the heat transfer which occurs during evaporation of water. It was named after the place where it was invented — the small mining town of Coolgardie, Western Australia, near Kalgoorlie-Boulder.
Coolgardie was the site of a gold rush in the early 1890s, prior to the Kalgoorlie-Boulder gold rush.
For the prospectors who had rushed here to find their fortune, one challenge was to extend the life of their perishable foods — hence the invention of the Coolgardie safe.
The safe was invented in the late 1890s by Arthur Patrick McCormick, who used the same principle as explorers and travelers in the Outback used to cool their canvas water bags: when the canvas bag is wet the fibers expand and it holds water. Some water seeps out and evaporates, especially if it is in a breeze, cooling the stored water.
This technology is commonly thought to have been adopted by explorer and scientist Sir Thomas Livingstone Mitchell, who had observed the way some Aborigines used kangaroo skins to carry water.
The Coolgardie Safe was made of wire mesh, hessian, a wooden frame and had a galvanised iron tray on top. The galvanised iron tray was
A crossword is a word puzzle that normally takes the form of a square or a rectangular grid of white and shaded squares. The goal is to fill the white squares with letters, forming words or phrases, by solving clues which lead to the answers. In languages that are written left-to-right, the answer words and phrases are placed in the grid from left to right and from top to bottom. The shaded squares are used to separate the words or phrases.
Squares in which answers begin are usually numbered. The clues are then referred to by these numbers and a direction, for example, "4-Across" or "20-Down". At the end of the clue the total number of letters is sometimes given, depending on the style of puzzle and country of publication. Some crosswords will also indicate the number of words in a given answer, should there be more than one.
The horizontal and vertical lines of white cells into which answers are written are commonly called entries or answers. The clues are usually called just that, or sometimes definitions. White cells are sometimes called lights, and the shaded cells are sometimes called darks, blanks, blocks, or just simply black squares or shaded squares.
A white cell that is
Five-pin bowling is a bowling variant which is played only in Canada, where most bowling alleys offer it, either alone or in combination with ten-pin bowling. It was devised around 1909 by Thomas F. Ryan in Toronto, Ontario, at his Toronto Bowling Club, in response to customers who complained that the ten-pin game was too strenuous. He cut five tenpins down to about 75% of their size, and used hand-sized hard rubber balls, thus inventing the original version of five-pin bowling.
The balls in five pin bowling are small enough to fit in the hand and therefore have no fingerholes. At the end of the lane there are five pins arranged in a V. In size they are midway between duckpins and ten pins, and they have a heavy rubber band around their middles, similar to the pins used in the rarely seen "rubberband duckpin" form of duckpin bowling, to make them move farther when struck. Unlike any other form of bowling popular in North America, the pins in five-pin bowling are worth different scoring point values, depending on their location in the V-formation. The centre pin is worth five points if knocked down, those on either side, three each, and the outermost pins, two each, giving a total
The Harrier, informally referred to as the Jump Jet, is a family of military jet aircraft capable of vertical/short takeoff and landing (V/STOL) operations. Historically the Harrier was developed in Britain to operate from ad-hoc facilities such as car parks or forest clearings, avoiding the need for large air bases vulnerable to tactical nuclear weapons. Later the design was adapted for use from aircraft carriers. The Harrier is also distinct as being of modern era, yet subsonic, contrasting with most of the major Western post-World War II-era attack aircraft, which tend to be supersonic.
There are two generations of four main variants of the Harrier family:
The Hawker Siddeley Harrier is the first generation-version and is also known as the AV-8A Harrier. The Sea Harrier is a naval strike/air defence fighter. The AV-8B and BAE Harrier II are the US and British variants respectively of the second generation Harrier aircraft.
Following an approach by the Bristol Engine Company in 1957 that they were planning a directed thrust engine, Hawker Aircraft came up with a design for an aeroplane that could meet the NATO specification for a "Light Tactical Support Fighter". There was no
A hydraulic press is a machine (see machine press) using a hydraulic cylinder to generate a compressive force. It uses the hydraulic equivalent of a mechanical lever, and was also known as a Bramah press after the inventor, Joseph Bramah, of England. He invented and was issued a patent on this press in 1795. As Bramah (who is also known for his development of the flush toilet) installed toilets, he studied the existing literature on the motion of fluids and put this knowledge into the development of the press.
The hydraulic press depends on Pascal's principle: the pressure throughout a closed system is constant. One part of the system is a piston acting as a pump, with a modest mechanical force acting on a small cross-sectional area; the other part is a piston with a larger area which generates a correspondingly large mechanical force. Only small-diameter tubing (which more easily resists pressure) is needed if the pump is separated from the press cylinder.
Pascal's law: Pressure on a confined fluid is transmitted undiminished and acts with equal force on equal areas and at 90 degrees to the container wall.
A fluid, such as oil, is displaced when either piston is pushed inward. The
The Crosley Icyball was an example of a gas-absorption refrigerator, as can be found today in recreational vehicles or campervans. Unlike most refrigerators, the Icyball had no moving parts and, instead of operating continuously, was manually cycled. Typically it would be charged in the morning and provide cooling throughout the heat of the day.
Absorption refrigerators and the more common mechanical refrigerators both cool by the evaporation of refrigerant. (Evaporation of a liquid causes cooling, as for example, liquid sweat on the skin evaporating feels cool, and the reverse process releases lots of heat.) In absorption refrigerators, the build up of pressure due to evaporation of refrigerant is relieved not by suction at the inlet of a compressor but by absorption into an absorptive medium (water in the case of the Icy Ball).
The IcyBall system moves heat from the refrigerated cabinet to the warmer room by using ammonia as the refrigerant. It consists of two metal balls: a hot ball, which, in the fully charged state, contains the absorber (water), and a cold ball containing liquid ammonia. These are joined by a pipe in the shape of an inverted U. The pipe allows ammonia gas to
In 1827, Anyos Jedlik started experimenting with electromagnetic rotating devices which he called electromagnetic self-rotors. In the prototype of the single-pole electric starter (finished between 1852 and 1854) both the stationary and the revolving parts were electromagnetic. He formulated the concept of the dynamo at least 6 years before Siemens and Wheatstone. In essence the concept is that instead of permanent magnets, two electromagnets opposite to each other induce the magnetic field around the rotor.
A jet engine is a reaction engine that discharges a fast moving jet which generates thrust by jet propulsion in accordance with Newton's laws of motion. This broad definition of jet engines includes turbojets, turbofans, rockets, ramjets, and pulse jets. In general, most jet engines are internal combustion engines but non-combusting forms also exist.
In common parlance, the term jet engine loosely refers to an internal combustion airbreathing jet engine (a duct engine). These typically consist of an engine with a rotary (rotating) air compressor powered by a turbine ("Brayton cycle"), with the leftover power providing thrust via a propelling nozzle. These types of jet engines are primarily used by jet aircraft for long distance travel. Early jet aircraft used turbojet engines which were relatively inefficient for subsonic flight. Modern subsonic jet aircraft usually use high-bypass turbofan engines which offer high speed with fuel efficiency comparable (over long distances) to piston and propeller aeroengines.
Jet engines can be dated back to the invention of the aeolipile before the first century AD. This device used steam power directed through two nozzles to cause a sphere to
A Mechanical lubricator, or automatic lubricator, is a device fitted to a steam engine to supply lubricating oil to the cylinders and, sometimes, the bearings and axle box mountings as well. There are various types of mechanical lubricator.
The displacement lubricator was introduced in the United Kingdom in 1860 by John Ramsbottom. It operates by allowing steam to enter a closed vessel containing oil. After condensing, the water sinks to the bottom of the vessel, causing the oil to rise and overflow into delivery pipes. The oil from the delivery pipes is introduced into the steam pipe, where it is atomised and carried to the valves and cylinders.
In early applications in steam locomotives, either two displacement lubricators (one for each cylinder) would be positioned at the front of the boiler near the valves, often on either side of the smokebox or one lubricator would be placed behind the smokebox. The behind smokebox configuration has the advantage that a good connection can be made to the steam pipe and was used by the Great Western Railway. It has the disadvantage that the lubricator's accessibility is reduced and additional drain pipes are required to be connected to the
A periscope is an instrument for observation from a concealed position. In its simplest form it consists of an outer case with mirrors at each end set parallel to each other at a 45-degree angle. This form of periscope, with the addition of two simple lenses, served for observation purposes in the trenches during World War I. Military personnel also use periscopes in some gun turrets and in armoured vehicles.
More complex periscopes, using prisms instead of mirrors, and providing magnification, operate on submarines. The overall design of the classical submarine periscope is very simple: two telescopes pointed into each other. If the two telescopes have different individual magnification, the difference between them causes an overall magnification or reduction.
In 1854 Hippolyte Marié-Davy invented the first naval periscope, consisting of a vertical tube with two small mirrors fixed at each end at 45°. Simon Lake used periscopes in his submarines in 1902. Sir Howard Grubb perfected the device in World War I. Morgan Robertson (1861–1915) claimed to have tried to patent the periscope: he described a submarine using a periscope in his fictional works.
Periscopes, in some cases fixed
The Ross rifle was a notoriously inefficient straight-pull bolt action .303 inch calibre rifle produced in Canada from 1903 until the middle of the First World War.
The Ross .303 had many faults in the adverse environment imposed by trench warfare, and after numerous complaints the replacement of all Ross rifles in the three Canadian Divisions by the Lee-Enfield was ordered.
Snipers, however retained a considerable fondness for the weapon.
A sporting version using the new .280 Ross cartridge was produced for some time, and both the Ross rifle and the .280 calibre "magnum" round acquired a very considerable international reputation among target shooters, deer-stalkers and safari hunters.
During the Second Boer War, a minor diplomatic fight broke out between Canada and the United Kingdom, after the latter refused to sell or license the Lee-Enfield SMLE design for production in Canada. Sir Charles Ross, Bart., a Scottish nobleman, soldier, inventor and entrepreneurial businessman, offered his newly designed straight-pull rifle as a replacement. Ross was well connected in Canadian society and eventually landed his first contract in 1903 for 12,000 Mark I Ross rifles.
In this design,
The Rumford fireplace is a tall, shallow fireplace designed by Sir Benjamin Thompson, Count Rumford, an Anglo-American physicist who was known for his investigations of heat.
Rumford applied his knowledge of heat to the improvement of fireplaces. He made them smaller and shallower with widely angled covings so they would radiate better. And he streamlined the throat, or in his words "rounded off the breast" so as to "remove those local hindrances which forcibly prevent the smoke from following its natural tendency to go up the chimney..."
Rumford wrote two papers detailing his improvements on fireplaces in 1796 and 1798. He was well known and widely read in his lifetime and almost immediately in the 1790s his "Rumford fireplace" became state-of-the-art worldwide.
Today, with the extensive restoration of old and historic houses and the renewed popularity of early American and classical architecture in new construction, Rumford fireplaces are enjoying a comeback. Rumford fireplaces are generally appreciated for their tall classic elegance and their heating efficiency.
The Rumford fireplace created a sensation in London when he introduced the idea of restricting the chimney opening
In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5% to 11% chromium content by mass.
Stainless steel does not readily corrode, rust or stain with water as ordinary steel does, but despite the name it is not fully stain-proof, most notably under low oxygen, high salinity, or poor circulation environments. It is also called corrosion-resistant steel or CRES when the alloy type and grade are not detailed, particularly in the aviation industry. There are different grades and surface finishes of stainless steel to suit the environment the alloy must endure. Stainless steel is used where both the properties of steel and resistance to corrosion are required.
Stainless steel differs from carbon steel by the amount of chromium present. Unprotected carbon steel rusts readily when exposed to air and moisture. This iron oxide film (the rust) is active and accelerates corrosion by forming more iron oxide, and due to the dissimilar size of the iron and iron oxide molecules (iron oxide is larger) these tend to flake and fall away. Stainless steels contain sufficient chromium to form a passive film of