Governments and private organizations have developed car classification schemes that are used for various purposes including regulation and categorization, among others. This article details used classification schemes in use worldwide; this following table summarises common classifications for cars. Microcars and their Japanese equivalent— kei cars— are the smallest category of automobile. Microcars straddle the boundary between car and motorbike, are covered by separate regulations to normal cars, resulting in relaxed requirements for registration and licensing. Engine size is 700 cc or less, microcars have three or four wheels. Microcars are most popular in Europe, where they originated following World War II; the predecessors to micro cars are Cycle cars. Kei cars have been used in Japan since 1949. Examples of microcars and kei cars: Honda Life Isetta Tata Nano The smallest category of vehicles that are registered as normal cars is called A-segment in Europe, or "city car" in Europe and the United States.
The United States Environmental Protection Agency defines this category as "minicompact", however this term is not used. The equivalents of A-segment cars have been produced since the early 1920s, however the category increased in popularity in the late 1950s when the original Fiat 500 and BMC Mini were released. Examples of A-segment / city cars / minicompact cars: Fiat 500 Hyundai i10 Toyota Aygo The next larger category small cars is called B-segment Europe, supermini in the United Kingdom and subcompact in the United States; the size of a subcompact car is defined by the United States Environmental Protection Agency, as having a combined interior and cargo volume of between 85–99 cubic feet. Since the EPA's smaller minicompact category is not as used by the general public, A-segment cars are sometimes called subcompacts in the United States. In Europe and Great Britain, the B-segment and supermini categories do not any formal definitions based on size. Early supermini cars in Great Britain include Vauxhall Chevette.
In the United States, the first locally-built subcompact cars were the 1970 AMC Gremlin, Chevrolet Vega, Ford Pinto. Examples of B-segment / supermini / subcompact cars: Chevrolet Sonic Hyundai Accent Volkswagen Polo The largest category of small cars is called C-segment or small family car in Europe, compact car in the United States; the size of a compact car is defined by the United States Environmental Protection Agency, as having a combined interior and cargo volume of 100–109 cu ft. Examples of C-segment / compact / small family cars: Peugeot 308 Toyota Auris Renault Megane In Europe, the third largest category for passenger cars is called D-segment or large family car. In the United States, the equivalent term is intermediate cars; the U. S. Environmental Protection Agency defines a mid-size car as having a combined passenger and cargo volume of 110–119 cu ft. Examples of D-segment / large family / mid-size cars: Chevrolet Malibu Ford Mondeo Kia Optima In Europe, the second largest category for passenger cars is E-segment / executive car, which are luxury cars.
In other countries, the equivalent terms are full-size car or large car, which are used for affordable large cars that aren't considered luxury cars. Examples of non-luxury full-size cars: Chevrolet Impala Ford Falcon Toyota Avalon Minivan is an American car classification for vehicles which are designed to transport passengers in the rear seating row, have reconfigurable seats in two or three rows; the equivalent terms in British English are people carrier and people mover. Minivans have a'one-box' or'two-box' body configuration, a high roof, a flat floor, a sliding door for rear passengers and high H-point seating. Mini MPV is the smallest size of MPVs and the vehicles are built on the platforms of B-segment hatchback models. Examples of Mini MPVs: Fiat 500L Honda Fit Ford B-Max Compact MPV is the middle size of MPVs; the Compact MPV size class sits between large MPV size classes. Compact MPVs remain predominantly a European phenomenon, although they are built and sold in many Latin American and Asian markets.
Examples of Compact MPVs: Renault Scenic Volkswagen Touran Ford C-Max The largest size of minivans is referred to as'Large MPV' and became popular following the introduction of the 1984 Renault Espace and Dodge Caravan. Since the 1990s, the smaller Compact MPV and Mini MPV sizes of minivans have become popular. If the term'minivan' is used without specifying a size, it refers to a Large MPV. Examples of Large MPVs: Dodge Grand Caravan Ford S-Max Toyota Sienna The premium compact class is the smallest category of luxury cars, it became popular in the mid-2000s, when European manufacturers— such as Audi, BMW and Mercedes-Benz— introduced new entry level models that were smaller and cheaper than their compact executive models. Examples of premium compact cars: Audi A3 Buick Verano Lexus CT200h A compact executive car is a premium car larger than a premium compact and smaller than an executive car. Compact executive cars are equivalent size to mid-size cars and are part of the D-segment in the European car classification.
In North American terms, close equivalents are "luxury compact" and "entry-level luxury car", although the latter is used for the smaller premium compact cars. Examples of compact executive cars: Audi A4 BMW 3 Series Buick Regal An executive car is a premium car larger than a compact executive and smaller than an full-size luxury car. Executive cars are classified as E-segment cars in the European car classification. In the United States and several other coun
SU carburettors are a brand of carburettor of the constant depression type. The design remained in quantity production for much of the twentieth century; the S. U. Carburetter Company Limited manufactured dual-choke updraught carburettors for aero-engines such as the Rolls-Royce Merlin and Rolls-Royce Griffon. Herbert Skinner, pioneer motorist and an active participant in the development of the petrol engine, invented his Union carburettor in 1904, his much younger brother Carl Skinner a motoring enthusiast, had joined the Farman Automobile Co in London in 1899. He helped Herbert to develop the carburettor. Herbert's son could remember his mother sewing the first leather bellows, it would be given on loan to The Science Museum, South Kensington in 1934. In 1905 Herbert applied for a patent, granted in early 1906. Carl sold his interest in footwear business Lilley & Skinner and became a partner in G Wailes & Co of Euston Road, manufacturers of their carburettor. Herbert continued to develop and patent improvements through to the 1920s including the replacement of the leather bellows by a brass piston though he was a full-time director and divisional manager of Lilley & Skinner.
S. U. Company Limited —Skinner-Union— was incorporated in August 1910 to acquire Herbert's carburettor inventions and it began manufacture of the carburettors in a factory at Prince of Wales Road, Kentish Town in North London. Sales were slow. Following the outbreak of war in 1914 carburettor production nearly stopped with the factory making machine gun parts and some aircraft carburettors. With peace in 1918 production resumed but sales remained slow and the company was not profitable so Carl Skinner approached his customer, W. R. Morris, managed to sell him the business. Carl Skinner became a director of Morris's held empire and remained managing director of S. U. until he retired in 1948 aged 65. Production was moved to the W R Morris owned Wolseley factory at Birmingham. In 1936 W R Morris sold many of his held businesses including S. U. to his listed company, Morris Motors. Manufacture continued, now by The S. U. Carburetter Company Limited, incorporated 15 September 1936 as part of the Morris Organization known as the Nuffield Organization.
The S. U. Carburetter Company Limited of 1936 was voluntarily liquidated in December 1994. In 1996 the name and rights were acquired by Burlen Fuel Systems Limited of Salisbury which incorporated an new company with the name The S. U. Carburetter Company Limited which continues to manufacture carburettors and components for the classic car market. S. U. carburettors were used not only in Morris's Morris and MG products but Rolls-Royce, Rover, Turner, Jaguar and Swedish Volvo, Saab 99 automobiles for much of the twentieth century. S. U. produced carburettors for aircraft engines including the early versions of the Rolls-Royce Merlin, but these were of the conventional fixed-jet updraught type rather than the firm's patented constant-depression design. They remained on production cars through to 1993 in the Mini and the Maestro by which time the company had become part of the Rover Group. Hitachi built carburettors based on the SU design which were used on the Datsun 240Z, Datsun 260Z and other Datsun Cars.
While these appear the same, only their needles are interchangeable. SU carburettors featured a variable venturi controlled by a piston; this piston has a tapered, conical metering rod that fits inside an orifice which admits fuel into the airstream passing through the carburettor. Since the needle is tapered, as it rises and falls it opens and closes the opening in the jet, regulating the passage of fuel, so the movement of the piston controls the amount of fuel delivered, depending on engine demand; the exact dimensions of the taper are tailored during engine development. The flow of air through the venturi creates a reduced static pressure in the venturi; this pressure drop is communicated to the upper side of the piston via an air passage. The underside of the piston is open to atmospheric pressure; the difference in pressure between the two sides of the piston lifts the piston. Opposing this are the weight of the piston and the force of a spring, compressed by the piston rising; because the spring is operating over a small part of its possible range of extension, its force is constant.
Under steady state conditions the upwards and downwards forces on the piston are equal and opposite, the piston does not move. If the airflow into the engine is increased - by opening the throttle plate, or by allowing the engine revs to rise with the throttle plate at a constant setting - the pressure drop in the venturi increases, the pressure above the piston falls, the piston is pushed upwards, increasing the size of the venturi, until the pressure drop in the venturi returns to its nominal level. If the airflow into the engine is reduced, the piston will fall; the result is that the pressure drop in the venturi remains the same regardless of the speed of the airflow - hence the name "constant depression" for carburettors operating on this principle - but the piston rises and falls according to the rate of air delivery. Since the position of the piston controls the position of the needle in the jet and thus the open area of the jet, while the depression in the venturi sucking fuel out of the jet remains constant, the rate of fuel delivery is always a definite function of the rate of air delivery.
The precise nature of the function is determined by the profile of the needle. With appropriate selection of the needle, the fuel delivery can be m
The Rover P4 series is a group of mid-size luxury saloon cars produced by the Rover Company from 1949 until 1964. They were designed by Gordon Bashford, their P4 designation is factory terminology for this group of cars and was not in day-to-day use by ordinary owners who would have used the appropriate consumer designations for their models such as Rover 90 or Rover 100. Production began in 1949 with the 6-cylinder 2.1-litre Rover 75. Four years a 2-litre 4-cylinder Rover 60 was brought to the market to fit below the 75 and a 2.6-litre 6-cylinder Rover 90 to top the three-car range. Several variations followed; these cars are much part of British culture and became known as the'Auntie' Rovers. They were driven by royalty including Grace Kelly; the P4 series was supplemented in September 1958 by a new conservatively shaped Rover 3-litre P5 but the P4 series stayed in production until 1964 and their replacement by the Rover 2000. The earlier cars used a Rover engine from the 1948 Rover 75. A four-speed manual transmission was used with a column-mounted gearchange at first and floor-mounted unit from September 1953.
At first the gearbox only had synchromesh on third and top but it was added to second gear as well in 1953. A freewheel clutch, a traditional Rover feature, was fitted to cars without overdrive until mid-1959, when it was removed from the specifications, shortly before the London Motor Show in October that year; the cars had a separate chassis with independent suspension by coil springs at the front and a live axle with half-elliptical leaf springs at the rear. The brakes on early cars were operated by a hybrid hydro-mechanical system but became hydraulic in 1950. Girling disc brakes replaced drums at the front from October 1959; the complete body shells were made by the Pressed Steel company and featured aluminium/magnesium alloy doors, boot lid and bonnets until the final 95/110 models, which were all steel to reduce costs. The P4 series was one of the last UK cars to incorporate rear-hinged "suicide" doors. Announced by Managing Director Spencer Wilks on 23 September 1949 the new Rover 75, now the only Rover in production, was first displayed at the opening day of the Earls Court Motor Show on 28 September 1949.
It featured unusual modern styling in stark contrast with the outdated Rover 75 it replaced. Gone were the traditional radiator, separate headlamps and external running boards. In their place were a chromium grille, recessed headlamps and a streamlined body the whole width of the chassis. A steering column-mounted gear lever was fitted; the car's styling was derived from the controversial 1947 Studebakers. The Rover executives purchased two such vehicles and fitted the body from one of them to a prototype P4 chassis to create a development mule. James Taylor's book'Rover P4 – The Complete Story' says that this vehicle was affectionately known as the'Roverbaker' hybrid. Malcolm Bobbit states "The P4 set the seal on the future with a vengeance. Rover defied its critics with the P4's new look and to get some idea of the shock of the new, consider some of its rivals... astonishment at the P4's courageous styling." The P3 had no boot at all yet, considered rather more than adequate. The new car's bonnet-like extension to its rear was ridiculed.
All the new car's proportions were different from all the other new cars. Another, at the time minor, distinctive feature but this one did not catch on was the centrally mounted light in the grille where most other manufacturers of good quality cars provided a pair, one fog and one driving light separately mounted behind the bumper. Known as the "Cyclops eye" it was discontinued in the new grille announced 23 October 1952. Power came from a more powerful version of the previous model's 2.1 L Rover IOE straight-6 engine now with chromium-plated cylinder bores, an aluminium cylinder head with built-in induction manifold and a pair of horizontal instead of downdraught carburetters. A four-speed manual transmission was used with a column-mounted gear lever, replaced by a floor-mounted mechanism in September 1953. A car tested by The Motor magazine in 1949 had a top speed of 83.5 mph and could accelerate from 0–60 mph in 21.6 seconds. A fuel consumption of 27.8 miles per imperial gallon was recorded.
The test car cost £1106 including taxes. The turning circle was 37 feet. "... and I believe that there is no finer car built in the world today." Bob Dearborn, Tester Road & Track. Road test no. F-4-52, August 1952. After four years of the one model policy Rover returned to a range of the one car but three different sized engines. In September 1953 it announced it would supply a four-cylinder Rover 60 and a 2.6-litre Rover 90 adding them to the 75's 2.1-litre six. Rover's stated intention was "to cater for a wider field of motorists who require a quality car with varying degrees of economical running costs and performance". On the same day there were modifications announced which were accordingly shared by all three: a curved central gear change lever; this was Rover's response to the dislike of many motorists for the steering column gear change with its complex linkages. The shape of the new lever still allowed three people to make use of the front bench seat. Parking lights were mounted on top of the front mudguards, the disused apertures below were used for reflectors – and for traffic indicators.
Rover announced an all-round reduction in Rover and Land-Rover prices. This was a response to a slump in both export sales of all British cars; the 2.103 litres IOE engine continued. Th
Maurice Fernand Cary Wilks was an automotive and aeronautical engineer, by the time of his death in 1963, was the chairman of the Rover Company, a British car manufacturer. He was responsible for the inspiration and concept work that led to the development of the Land Rover off-road utility vehicle. Wilks was born on 19 August 1904 at Hayling Island, England, the youngest of five sons and one daughter of Thomas Wilks, a Director of Leather Co and his wife Jane Eliza, a Suffragette. One of his brothers was Spencer Wilks who became managing director and president of the Rover Car Company, he was educated at Malvern College. Maurice Wilks worked from 1922 to 1926 for the Hillman Motor Car Company in Coventry. In 1926 he went to work for General Motors in the United States but after two years in the U. S. returned to Hillman. Wilks remained at Hillman as a planning engineer until 1930, when he moved to the Rover Company as chief engineer following his much older brother, Spencer. Spencer Wilks had been brought in from Hillman in September 1929 by Rover's Frank Searle made general manager and given a seat on Rover's board the following year.
Spencer would be appointed managing director of Rover from 1932In 1930 Spencer and Maurice Wilks on Spencer's appointment to the board made the important decision to make only high quality cars. During World War II, Wilks led Rover's team developing Frank Whittle's gas turbine aircraft engines. Experiencing difficulties with Whittle's team Rover passed the project to Rolls-Royce in 1943. After the war, Wilks continued working with gas turbine engines, leading to Rover unveiling the first gas turbine powered car in 1949. Shortly after the war, whilst at his farm in Anglesey, who used an army surplus Willys Jeep for farm work, his brother Spencer, visiting him, were inspired to develop and produce a utility four-wheel-drive vehicle for farmers, the name Land Rover was coined for it. By the summer of 1947 Rover had built a prototype Land Rover vehicle based on a Jeep chassis. In September 1947, the Rover company authorised the production of 50 pre-production models for evaluation purposes; the Land Rover was launched to the world at the 1948 Amsterdam Motor Show.
Maurice Wilks was a leading light in the establishment and development of the proving ground facilities of the Motor Industry Research Association. Maurice Wilks remained chief engineer until appointed technical director in 1946, he was appointed joint managing director with brother Spencer Wilks in August 1956 and succeeded his brother as managing director in November 1960. In January 1962 preferring policy to day-to-day management he was appointed chairman of the Rover Company in succession to his older brother Spencer Wilks; the managing director appointment was given to W F F Martin-Hurst. Wilks died at his farm near Newborough, Anglesey, on 8 September 1963, his obituary in The Times described him as shunning publicity but added that he was farsighted and regarded as one of the industry's outstanding engineers with a brilliant knowledge of engineering detail. He was survived by three children, he married Barbara Martin-Hurst in 1937. From the early 1930s, until merged with British Leyland, Rover had much of the nature of a family business.
Maurice Wilks's elder brother, Spencer Bernau Wilks, was general manager from September 1929 managing director of Rover from 1932 until 1957 when he was appointed chairman of the board of directors. Spencer was hired by Rover managing director, Frank Searle, from his position of joint managing director of Hillman following the purchase of Hillman by the Rootes brothers. Spencer brought Maurice from Hillman to Rover the following year to be Rover's chief engineer. Aged 70 Spencer retired from the chair in favour of his much younger brother at the beginning of 1962 remaining on the board in a non-executive capacity, he was made president of Rover in 1967. William Martin-Hurst Rover's well-liked managing director, was a Maurice Wilks relative by marriage. Peter Wilks, son of Geoffrey Wilks, took over his uncle Maurice Wilks' technical directorship in 1963 and became engineering director but he retired for health reasons in July 1971 when only 51 and died the following year. Spencer King was a nephew of Maurice Wilks.
He took over as technical director on the retirement of Peter Wilks. Spencer Wilks and John Black of the Standard Motor Company married sisters, daughters of William Hillman bicycle and automobile manufacturer. Still photograph of M C Wilks by British Pathé
Overdrive is the operation of an automobile cruising at sustained speed with reduced engine revolutions per minute, leading to better fuel consumption, lower noise, lower wear. Use of the term is confused, as it is applied to several related, meanings; the most fundamental meaning is that of an overall gear ratio between engine and wheels, such that the car is over-geared, cannot reach its potential top speed, i.e. the car could travel faster if it were in a lower gear, with the engine turning at higher RPM. The purpose of such a gear may not be obvious; the power produced by an engine increases with the engine's RPM to a maximum falls away. The point of maximum power is somewhat lower than the absolute maximum RPM to which the engine is limited, the "redline" RPM. A car's speed is limited by the power required to drive it against air resistance, which increases with speed. At the maximum possible speed, the engine is running at its point of maximum power, or power peak, the car is traveling at the speed where air resistance equals that maximum power.
There is therefore one specific gear ratio at which the car can achieve its maximum speed: the one that matches that engine speed with that travel speed. At travel speeds below this maximum, there is a range of gear ratios that can match engine power to air resistance, the most fuel efficient is the one that results in the lowest engine speed. Therefore, a car needs one gearing to reach maximum speed but another to reach maximum fuel efficiency at a lower speed. With the early development of cars and the universal rear-wheel drive layout, the final drive ratio for fast cars was chosen to give the ratio for maximum speed; the gearbox was designed so that, for efficiency, the fastest ratio would be a "direct-drive" or "straight-through" 1:1 ratio, avoiding frictional losses in the gears. Achieving an overdriven ratio for cruising thus required a gearbox ratio higher than this, i.e. the gearbox output shaft rotating faster than the engine. The propeller shaft linking gearbox and rear axle is thus overdriven, a transmission capable of doing this became termed an "overdrive" transmission.
The device for achieving an overdrive transmission was a small separate gearbox, attached to the rear of the main gearbox and controlled by its own shift lever. These were optional on some models of the same car; as popular cars became faster relative to legal limits and fuel costs became more important after the 1973 oil crisis, the use of 5-speed gearboxes became more common in mass-market cars. These had a direct fourth gear with an overdrive 5th gear, replacing the need for the separate overdrive gearbox. With the popularity of front wheel drive cars, the separate gearbox and final drive have merged into a single transaxle. There is no longer a propeller shaft and so one meaning of "overdrive" can no longer be applied; however the fundamental meaning, that of an overall ratio higher than the ratio for maximum speed, still applies. Although the deliberate labelling of an overdrive is now rare, the underlying feature is now found across all cars; the power needed to propel a car at any given set of conditions and speed is straightforward to calculate, based on the total weight and the vehicle's speed.
These produce two primary forces slowing the car: air drag. The former varies with the speed of the vehicle, while the latter varies with the square of the speed. Calculating these from first principles is difficult due to a variety of real-world factors, so this is measured directly in wind tunnels and similar systems; the power produced by an engine increases with the engine's RPM to a maximum falls away. This is known as the point of maximum power. Given a curve describing the overall drag on the vehicle, it is simple to find the speed at which the total drag forces are the same as the maximum power of the engine; this defines the maximum speed. The rotational speed of the wheels for that given forward speed is simple to calculate, it is the tire circumference multiplied by the RPM; as the tire RPM at maximum speed is not the same as the engine RPM at that power, a transmission is used with a gear ratio to convert one to the other. At slightly lower speeds than maximum, the total drag on the vehicle is less, the engine needs to deliver this reduced amount of power.
In this case the RPM of the engine has changed while the RPM of the wheels has changed little. This condition calls for a different gear ratio. If one is not supplied, the engine is forced to run at a higher RPM than optimal; as the engine requires more power to overcome internal friction at higher RPM, this means more fuel is used to keep the engine running at this speed. Every cycle of the engine leads to wear, so keeping the engine at higher RPM is unfavorable for engine life. Additionally, the sound of an engine is related to the RPM, so running at lower RPM is quieter. If one runs the same RPM transmission exercise outlined above for maximum speed, but instead sets the "maximum speed" to that of highway cruising, the output is a higher gear ratio that provides ideal fuel mileage. In an era when cars were not able to travel fast, the maximum power point might be near enough to the desired speed that additional gears were not needed, but as more powerful cars appeared during the 1960s, this disparity between the maximum power point and desired speed grew considerably.
This meant that cars were operating far from their most efficient point. As the desire for better fuel economy grew after the 1973 oil crisis, the need for a "cruising gear" became more pressing. Th
An engine or motor is a machine designed to convert one form of energy into mechanical energy. Heat engines, like the internal combustion engine, burn a fuel to create heat, used to do work. Electric motors convert electrical energy into mechanical motion, pneumatic motors use compressed air, clockwork motors in wind-up toys use elastic energy. In biological systems, molecular motors, like myosins in muscles, use chemical energy to create forces and motion; the word engine derives from Old French engin, from the Latin ingenium–the root of the word ingenious. Pre-industrial weapons of war, such as catapults and battering rams, were called siege engines, knowledge of how to construct them was treated as a military secret; the word gin, as in cotton gin, is short for engine. Most mechanical devices invented during the industrial revolution were described as engines—the steam engine being a notable example. However, the original steam engines, such as those by Thomas Savery, were not mechanical engines but pumps.
In this manner, a fire engine in its original form was a water pump, with the engine being transported to the fire by horses. In modern usage, the term engine describes devices, like steam engines and internal combustion engines, that burn or otherwise consume fuel to perform mechanical work by exerting a torque or linear force. Devices converting heat energy into motion are referred to as engines. Examples of engines which exert a torque include the familiar automobile gasoline and diesel engines, as well as turboshafts. Examples of engines which produce thrust include rockets; when the internal combustion engine was invented, the term motor was used to distinguish it from the steam engine—which was in wide use at the time, powering locomotives and other vehicles such as steam rollers. The term motor derives from the Latin verb moto which means to maintain motion, thus a motor is a device. Motor and engine are interchangeable in standard English. In some engineering jargons, the two words have different meanings, in which engine is a device that burns or otherwise consumes fuel, changing its chemical composition, a motor is a device driven by electricity, air, or hydraulic pressure, which does not change the chemical composition of its energy source.
However, rocketry uses the term rocket motor though they consume fuel. A heat engine may serve as a prime mover—a component that transforms the flow or changes in pressure of a fluid into mechanical energy. An automobile powered by an internal combustion engine may make use of various motors and pumps, but all such devices derive their power from the engine. Another way of looking at it is that a motor receives power from an external source, converts it into mechanical energy, while an engine creates power from pressure. Simple machines, such as the club and oar, are prehistoric. More complex engines using human power, animal power, water power, wind power and steam power date back to antiquity. Human power was focused by the use of simple engines, such as the capstan, windlass or treadmill, with ropes and block and tackle arrangements; these were used in cranes and aboard ships in Ancient Greece, as well as in mines, water pumps and siege engines in Ancient Rome. The writers of those times, including Vitruvius and Pliny the Elder, treat these engines as commonplace, so their invention may be more ancient.
By the 1st century AD, cattle and horses were used in mills, driving machines similar to those powered by humans in earlier times. According to Strabo, a water powered mill was built in Kaberia of the kingdom of Mithridates during the 1st century BC. Use of water wheels in mills spread throughout the Roman Empire over the next few centuries; some were quite complex, with aqueducts and sluices to maintain and channel the water, along with systems of gears, or toothed-wheels made of wood and metal to regulate the speed of rotation. More sophisticated small devices, such as the Antikythera Mechanism used complex trains of gears and dials to act as calendars or predict astronomical events. In a poem by Ausonius in the 4th century AD, he mentions a stone-cutting saw powered by water. Hero of Alexandria is credited with many such wind and steam powered machines in the 1st century AD, including the Aeolipile and the vending machine these machines were associated with worship, such as animated altars and automated temple doors.
Medieval Muslim engineers employed gears in mills and water-raising machines, used dams as a source of water power to provide additional power to watermills and water-raising machines. In the medieval Islamic world, such advances made it possible to mechanize many industrial tasks carried out by manual labour. In 1206, al-Jazari employed a crank-conrod system for two of his water-raising machines. A rudimentary steam turbine device was described by Taqi al-Din in 1551 and by Giovanni Branca in 1629. In the 13th century, the solid rocket motor was invented in China. Driven by gunpowder, this simplest form of internal combustion engine was unable to deliver sustained power, but was useful for propelling weaponry at high speeds towards enemies in battle and for fireworks. After invention, this innovation spread throughout Europe; the 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 he
British Leyland was an automotive engineering and manufacturing conglomerate formed in the United Kingdom in 1968 as British Leyland Motor Corporation Ltd, following the merger of Leyland Motors and British Motor Holdings. It was nationalised in 1975, when the UK government created a holding company called British Leyland BL, in 1978, it incorporated much of the British-owned motor vehicle industry, which constituted 40 percent of the UK car market, with roots going back to 1895. Despite containing profitable marques such as Jaguar and Land Rover, as well as the best-selling Mini, British Leyland had a troubled history, leading to its eventual collapse in 1975 and subsequent nationalisation. After much restructuring and divestment of subsidiary companies, it was renamed as the Rover Group in 1986 becoming a subsidiary of British Aerospace and subsequently, BMW; the final surviving incarnation of the company as the MG Rover Group, which went into administration in 2005, bringing mass car production by British-owned manufacturers to an end.
MG and the Austin and Wolseley marques became part of China's SAIC, with whom MG Rover attempted to merge prior to administration. Today, Jaguar Land Rover and Leyland Trucks are the three most prominent former parts of British Leyland which are still active in the automotive industry, with SAIC-owned MG Motor continuing a small presence at the Longbridge site. Certain other related ex-BL businesses, such as Unipart, continue to operate independently. BLMC was created on 17 January 1968 by the merger of British Motor Holdings and Leyland Motor Corporation, encouraged by Tony Benn as chairman of the Industrial Reorganisation Committee created by the first Wilson Government. At the time, LMC was a successful manufacturer; the Government was hopeful LMC's expertise would revive the ailing BMH, create a "British General Motors". The merger combined most of the remaining independent British car manufacturing companies and included car and truck manufacturers and more diverse enterprises including construction equipment, metal casting companies, road surface manufacturers.
The new corporation was arranged into seven divisions under Sir Donald Stokes. While BMH was the UK's largest car manufacturer, it offered a range of dated vehicles, including the Morris Minor, introduced in 1948 and the Austin Cambridge and Morris Oxford, which dated back to 1959. Although BMH had enjoyed great success in the 1960s with both the Mini and the 1100/1300, both cars were infamously underpriced and despite their pioneering but unproven front wheel drive engineering, warranty costs had been crippling and had badly eroded those models' profitability. After the merger, Lord Stokes was horrified to find that BMH had no plans to replace the elderly designs in its portfolio. BMH's design efforts prior to the merger had focused on unfortunate niche market models such as the Austin Maxi and the Austin 3 litre, a car with no discernible place in the market; the lack of attention to the development of new mass-market models meant that BMH had nothing in the way of new models in the pipeline to compete with popular rivals such as Ford's Escort and Cortina.
Lord Stokes instigated plans to design and introduce new models quickly. The first result of this crash programme was the Morris Marina in early 1971, it used parts from various BL models with new bodywork to produce BL's mass-market competitor. It was one of the strongest-selling cars in Britain during the 1970s, although by the end of production in 1980 it was regarded as a dismal product that had damaged the company's reputation; the Austin Allegro, launched in 1973, earned a unwanted reputation over its 10-year production life. The company became an infamous monument to the industrial turmoil. Industrial action instigated by militant shop stewards brought BL's manufacturing capability to its knees. Despite the duplication of production facilities as a result of the merger, there were multiple single points of failure in the company's production network which meant that a strike in a single plant could stop many of the others. Both Ford and General Motors had mitigated against this years before by merging their separate British and German subsidiaries and product lines, so that production could be sourced from either British or Continental European plants in the event of industrial unrest.
The upshot was that both Ford and Vauxhall overtook BL to become Britain's two best selling marques, a title they hold to the present day. At the same time, a tide of Japanese imports, spearheaded by Nissan and Toyota exploited both BL's inability to supply its customers and its declining reputation for quality – by the end of the 1970s, the British government had introduced protectionist measures in the form of import quotas on Japanese manufacturers in order to protect the ailing domestic producers, which it was helping to sustain. At its peak, BLMC owned 40 manufacturing plants across the country. Before the merger BMH had included theoretically competing marques that were