Things everybody “knows” about steam engines
Watt invented it, Rocket came first, and steam always does the pushing. Gently corrected.
MythJames Watt invented the steam engine.
FactThe first recorded Newcomen engine was put up near Dudley Castle, Staffordshire, in 1712. Encyclopaedia Britannica: Thomas Newcomen In May 1765 Watt came up with the separate condenser, his first and greatest invention. Encyclopaedia Britannica: James Watt
MythRocket was the first steam locomotive.
FactTrevithick built the world’s first steam railway locomotive in 1804. Science Museum blog: Steam train in Kensington Gardens Britannica says railway steam became a commercial success with Rocket in 1829. Encyclopaedia Britannica: steam engine
MythSteam does all the pushing in every steam engine.
FactIn a Newcomen engine the air does the pushing: steam is condensed to make a vacuum in the cylinder, and atmospheric pressure shoves the piston down. Encyclopaedia Britannica: Thomas Newcomen
MythGeorge Stephenson built Rocket on his own.
FactRocket was built in 1829 by Robert Stephenson and Company at the Forth Street Works in Newcastle. Science Museum blog: Stephenson’s Rocket returns to Newcastle Robert Stephenson was 25 when Rocket was built. Science Museum blog: Stephenson’s Rocket returns to Newcastle
MythWatt loved high-pressure steam.
FactWatt thought “strong steam” (high pressure) was too dangerous to harness; Trevithick went for it anyway. Encyclopaedia Britannica: Richard Trevithick
MythOne horsepower is exactly what one horse can do.
FactJames Watt fixed the horsepower after experiments with strong dray horses, and his figure is about 50 per cent more than an average horse can keep up. Encyclopaedia Britannica: horsepower
MythHero’s steam ball was used to power machines.
FactHero of Alexandria made the first known “steam engine”, but used it only to power toys and amuse visitors. Encyclopaedia Britannica: Heron of Alexandria
MythA flywheel spinning twice as fast stores twice the energy.
FactSpin a flywheel twice as fast and it stores four times the energy. Encyclopaedia Britannica: flywheel
MythEvery source agrees on Rocket’s top speed.
FactBritannica says Rocket reached 36 mph (58 km/h) for a short stretch. Encyclopaedia Britannica: Rocket The Science Museum puts Rocket’s record at 35 mph, three times its design speed, with an average of 15 mph in the trials. Science Museum blog: Stephenson’s Rocket returns to Newcastle
MythRocket is the oldest locomotive still around.
FactPuffing Billy, built in about 1814 by William Hedley, is the oldest surviving steam locomotive in the world. Science Museum blog: Steam train in Kensington Gardens