A steam train is very strong. 

A steam train is very strong. 


A steam locomotive is a machine on wheels. 


Steam engines started in the United Kingdom. Richard Trevithick built an engine that pulled a load in 1804. Later, George Stephenson built Locomotion No. 1. It was the first to carry passengers on a public railway in 1825. Some locomotives were very fast. The Mallard reached a record speed in 1938. Other engines were very big. The Union Pacific Big Boy is one of the largest. Most steam engines stopped working by the 1980s. Now, some still run on special tourist lines.
A steam locomotive is a machine on wheels that moves itself and other vehicles. 

How does this expansion turn into movement? The steam is let into cylinders at each end of the engine. 

Steam engines were first developed in the United Kingdom during the early 1800s.
Many famous locomotives were built with different goals in mind. Some were built for speed, while others were built for strength. 

Steam power was the main way to move trains for a long time.
A steam locomotive is a self-propelled engine on wheels that provides force to move itself and other vehicles. 

The mechanism of a steam locomotive relies on a specific physical process. First, the locomotive burns combustible material, such as coal, oil, or occasionally wood. This fuel heats water inside a large component called a boiler. As the water reaches its boiling point, it becomes gaseous steam. This steam expands significantly, increasing its volume by 1,600 to 1,700 times. 
Locomotives vary in their design and specific mechanical parts. Most models carry their fuel and water supplies in a tender, which is a separate car coupled to the locomotive. 
The history of the steam locomotive began in the United Kingdom during the early 19th century. Richard Trevithick was a pioneer in this field. He built a locomotive for trials at Coalbrookdale in 1802. In 1804, his locomotive at Pen-y-darren became the first known to haul a load over a distance.
Locomotives were often designed for specific purposes, such as extreme speed or massive strength. The LNER Class A4 4468 Mallard set an official speed record on 3 July 1938. 

Steam technology spread globally, though it faced unique challenges in different regions. In Russia, the first locomotive was built in 1834 by the Cherepanovs, but it was eventually replaced by horses due to a lack of coal. In Australia, the Trans-Australian Railway faced issues with magnesium chloride in the bore water. This mineralized water caused serious maintenance problems for the boilers. Because about half of a train's total load was often water, the high cost of treating this water led to the early adoption of diesel-electric locomotives. 
The era of steam began to fade in the early 1900s. Railways gradually transitioned to electric and diesel power, with full conversion beginning in the late 1930s. By the 1980s, most steam locomotives had been retired from regular service.
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