were finding their way into road vehicles, including, in 1905, Leyland buses. A major contribution to manufacturing was the introduction of the assembly line. The Crossley system even influenced Henry Ford, who visited Pottery Lane at the turn of the century. Crossley Motors In 1904 the company started production of motor cars and a separate company, Crossley Motors Ltd. was registered on 11 April 1906. This company was sold to Associated Equipment Company (AEC) in 1948, and vehicle production continued until 1958. Crossley Premier In 1919 Crossley Brothers bought Premier Gas Engines of Sandiacre, Nottingham, who built very large engines, and in 1935 changed their name to Crossley Premier Engines Ltd. The Nottingham factory was expanded, and production continued there until 1966. The engines were large horizontal heavy oil engines, typically used as generating plants or to power industrial plant such as air compressors, water pumps or mills. They were produced in a range of sizes, based on a standard cylinder unit, as either in-line or horizontally-opposed cylinder engines. They had clerestory combustion chambers with single inlet and exhaust valves above and below the chamber. Other manufacturers at the time, notably Brush, produced very similar engines as modular, opposed cylinder units. Crossley's were distinctive for using a monobloc head on each cylinder, although this was in the form of a self-supporting wet liner and the water jacket around the whole cylinder bank was a separate casting. The engines were also unusual for being one of the few practical applications of an electrically driven supercharger. This gave a relatively low boost pressure and was more of a scavenge blower, but it could increase output power by up to 50%. A pair of 16 cylinder opposed engines of 3,500 bhp, built for electrical generation in Jerusalem in the 1930s, were at the time the largest oil engines in the world. Like the earlier Ferranti steam generating plants, these placed half of the engine each side of a centrally-mounted alternator, thus reducing the maximum load on the crankshaft. A similar engine in a bombproof underground shelter was used to power the wartime Aspidistra transmitter. By the 1960s, although sales remained reasonable, the company had become unprofitable. The design of the engines then being made was essentially 40 years old, so in 1962 agreement was reached to use the French Pielstick design. Production of these engines, intended for ships, railway locomotives and electricity generation,