Information: - The American Locomotive Company, often shortened to ALCO, ALCo or Alco, designed, built and sold steam locomotives, diesel-electric locomotives, diesel engines and generators, specialized forgings, high quality steel, armed tanks and automobiles and produced nuclear energy. The American Locomotive Company was formed in 1901 by the merger of Schenectady Locomotive Engine Manufactory of Schenectady, New York with seven smaller locomotive manufacturers. - A steam locomotive is a railway locomotive that produces its pulling power through a steam engine. These locomotives are fueled by burning combustible materialusually coal/coke, wood, or oilto produce steam in a boiler. The steam moves reciprocating pistons which are mechanically connected to the locomotive's main wheels (drivers). Both fuel and water supplies are carried with the locomotive, either on the locomotive itself or in wagons (tenders) pulled behind. The first steam locomotive, made by Richard Trevithick, first operated on 21 February 1804, three years after the road locomotive he made in 1801. The first practical steam locomotive was built in 1812-13 by John Blenkinsop. - The diesel engine (correctly known as a compression-ignition or CI engine) is an internal combustion engine in which ignition of the fuel that has been injected into the combustion chamber is caused by the high temperature which a gas achieves (i.e. the air) when greatly compressed (adiabatic compression). Diesel engines work by compressing only the air. This increases the air temperature inside the cylinder to such a high degree that it ignites atomised diesel fuel that is injected into the combustion chamber. This contrasts with spark-ignition engines such as a petrol engine (gasoline engine) or gas engine (using a gaseous fuel as opposed to petrol), which use a spark plug to ignite an air-fuel mixture. In compression-ignition engines, glow plugs (combustion chamber pre-warmers) may be used to aid starting in cold weather, or when the engine uses a lower compression-ratio, or both. The original compression-ignition engine operates on the "constant pressure" cycle of gradual combustion and produces no audible knock. - The Milwaukee Road Class A was a class of high - speed , streamlined 4 - 4 - 2 '' Atlantic '' type steam locomotives built by the American Locomotive Company in 1935 - 37 to haul the Milwaukee Road 's Hiawatha express passenger trains . Numbered from # 1 - # 4 , they were among the last Atlantic type locomotives built in the United States , and certainly the largest and most powerful . The class were the first locomotives in the world built for daily operation at over 100 mph ( 160 km / h ) , and the first class built completely streamlined , bearing their casings their entire lives . Although partially supplanted by the larger F7 '' Hudsons '' from 1937 , they remained in top - flight service until the end . Locomotive # 3 was taken out of service in 1949 and cannibalised for spares to keep the other three running until 1951 . None survived into preservation . Given the information above, choose from the list below the object entity that exhibits the relation 'powerplant' with the subject 'milwaukee road class a'. Choices: - diesel engine - internal combustion engine - steam engine
Answer:
steam engine