James Watt and High-Pressure Steam
James Watt is often described as the father of the steam engine. Certainly, stationery steam engines of his design powered the factories of the industrial revolution, but, surprisingly, he had nothing to do with the development of the steam locomotive.
James Watt's engines used low-pressure steam. Steam was vented into a sealed cylinder with a piston at its top. The steam pushed out the air in the cylinder, and the steam itself was then vented out into a separate condenser. This created a vacuum in the cylinder, which drew the piston down, driving a flywheel and then the machinery attached to the flywheel. Finally, the flywheel would lift the piston back to the top of the cylinder, and the cycle would start again.
James Watt was opposed to use the of high-pressure steam because he felt it was unsafe. The engineering and metal working standards of the time meant the joints and pipes would frequently burst where high-pressure steam was used.
However, one of Boulton and Watt's employees – William Murdoch – would go onto develop projects in high-pressure steam –.
James Watt wasn't interested in high-pressure steam. He felt it was too dangerous for the engineering capabilities of his day. William Murdoch, however, would take the craft of high-pressure steam forward.
William Murdoch was born in Ayrshire in Scotland. In 1777, at the age of 23, we walked from Scotland to Birmingham – a distance of 300 miles – to ask James Watt for a job at the Boulton and Watt factory. Murdoch's skills were quickly recognised, and he became an important member of the team.
In 1779 Murdoch became the company's representative in Cornwall and supervised the erection and maintenance of the steam engines built in the area. Since the company was paid a royalty based on the efficiency of the engines, his work was vital to the success of the business – and he was very good at it.
Murdoch made suggestions for the improvement of the steam engines and contributed to several of the company's patents. There is evidence to suggest that the Sun and Planet gear patented by James Watt in 1781 was actually invented by William Murdoch.
William Murdoch was interested in high-pressure steam for many years. James Watt, distrustful of high-pressure steam, tried to discourage his schemes. However, in 1784 Murdoch made a working model of a steam carriage. He built more models, improving their design, throughout the 1780s, although his employers did not support this work. Some evidence suggests that he built a full-sized steam carriage in the 1790s. During that time, Richard Trevithick lived next door to Murdoch in Redruth, in Cornwall. Trevithick certainly knew of his experiments and may have helped him during this time. Murdoch does not seem to have done any further work in high-pressure steam, although Trevithick took his ideas forward.
In 1799 Murdoch patented, under his own name, a precursor of the steam turbine. He also developed the world's first pneumatic tube message system of the type still seen in some businesses.
In 1803 William Murdoch developed a steam cannon and then a steam gun that fired lead bullets. Neither of these inventions were successful.
James Watt retired from Boulton and Watt in 1800, and William Murdoch moved to Birmingham to manage the business, becoming a partner in the firm in 1810.
William Murdoch was a prolific inventor, as well as making substantial improvements to James Watt's steam engines, and advancing the concept of steam locomotion, he also made other important advances including in dyes; he created a cheaper form of isinglass for the brewing industry; and he was instrumental in the development of gaslighting. The first factory in the world to be fully lit by gas was a cotton mill in Manchester. The system was installed by Murdoch in 1805.
Murdoch, however, failed to apply for a patent for his gas lighting, and the Boulton and Watt company didn't fully capitalise on his work, leaving other businesses to benefit from the massive expansion of gaslighting in factories and towns in the early part of the nineteenth century.
From around 1818, William Murdoch developed a marine engineering branch of Boulton and Watt, equipping up to 60 vessels with steam engines. He retired from the business in 1830 and died in 1839
It is fitting that William Murdoch lived to hear of the Rainhill Trials and the development of the steam locomotive: it is a revolution that his early work with high-pressure steam initiated.
Although his name is little known today, William Murdoch was pivotal in the development of the industrial revolution.
It is Richard Trevithick who deserves the credit as the inventor of the steam locomotive.
Born at Redruth in Cornwall in 1771, Trevithick was fascinated by the steam pumping engines he saw at the mines in the area. He became aware of William Murdoch and may have been apprenticed to him in the early 1790s. In fact, he lived next door to Murdoch in Redruth in the later part of the 1790s.
Richard Trevithick became a mining engineer in 1797 and worked with Edward Bull to develop a new type of steam pumping engine, which was later found to infringe Boulton and Watt's patents. By that time, metal working standards had improved, and Trevithick dared to experiment with high-pressure steam. He made models in the late 1790s and built his first full-sized engine around 1799.
Although less efficient than Watt's engines, Trevithick's boilers were smaller and easier to install and used less water. Engines to his design began to be installed to pump water or drive machinery from the early 1800s. The firm of Boulton and Watt continued to decline to make high-pressure engines.
Richard Trevithick's most important contribution is to steam locomotion. He mounted one of his boilers on a carriage in 1801 and demonstrated it in the village of Camborne in Cornwall. The heavy steam carriage was soon damaged by the rutted roads. Undeterred, however, Richard Trevithick patented his steam engine in 1802 and built another steam carriage in London where he took passengers from Paddington to Holborn – a distance of about 4 miles. The carriage was expensive to run, and the project was soon abandoned. However, the idea of steam locomotion had been introduced to the public.
In 1804 one of Trevithick's stationery pumping engines exploded, killing four men. As a result, Trevithick developed safety valves for his engines.
The state of the roads in early nineteenth century England meant that steam carriages were not a practical proposition, and Trevithick turned his attention to running a steam locomotive on rails. In 1804 Richard Trevithick became the first person in the world to build a steam locomotive. With it, he won a £500 bet by hauling 10 tons of iron ore and 70 men 10 miles along iron rails in South Wales. This first train in the world ran at an average speed of 2.5 miles per hour.
A second engine was built, and Trevithick set up a circular track near Euston Road in London in 1808. He called the locomotive "Catch me Who Can" and charged visitors one shilling for a ride. However, the rails broke under the weight of the engine, and public interest waned.
Trevithick's problem was that cast-iron rails were too brittle for the heavy steam engines. He built no further locomotives after this failure, although he did work on many other engineering projects, including new designs of stationery high-pressure engines. He died penniless in 1833 and was buried in an unmarked grave in London.
Richard Trevithick built the world's first steam locomotive and demonstrated its potential. His ideas stimulated others and started the railway revolution of the nineteenth century.
Thank you for listening to this lesson. In the next lesson, we cover the further development of the steam locomotive.