Picture credits
The diagrams are our own. The engravings, paintings and photos are public domain on Wikimedia Commons, cropped and resized with no other changes.
Engravings, paintings and photos
Our own diagrams
Diagram of Hero’s aeolipile: a hollow ball mounted over a boiler, with two bent nozzles that squirt steam and make the ball spin
Our own drawing
Two simplified boilers side by side: in the fire-tube boiler hot gas runs through tubes inside the water; in the water-tube boiler water runs through tubes inside the hot gas
Our own drawing
Diagram of Watt’s separate condenser: the hot cylinder stays hot, and steam is led away to a separate vessel sitting in a tank of cold water
Our own drawing
Four small drawings of a piston, rod and crank at quarter turns, showing a straight push becoming a rotation
Our own drawing
Diagram of a double-acting steam engine: a boiler over a fire, a pipe to the slide valve, a piston in a cylinder, a connecting rod, a crank and a flywheel
Our own drawing
Diagram of a centrifugal governor: two heavy balls on arms spin with the engine and fly outwards as it speeds up, lifting a sleeve that closes the steam valve
Our own drawing
Diagram of a Newcomen atmospheric engine: a rocking beam with the piston on one end and a mine pump rod on the other, a cylinder over a boiler and a cold-water jet
Our own drawing
Diagram of a slide valve in two positions: steam goes to one side of the piston, then the valve slides and steam goes to the other side
Our own drawing
Diagram of the sun-and-planet gear: a gear on the end of the rod travels round a gear on the flywheel shaft
Our own drawing
Two drawings of a syringe with the end blocked: before, the air has plenty of room; after pushing the plunger in, the same air is squeezed into less room
Our own drawing
Diagram of a simple steam turbine: a jet of steam from a nozzle hits a ring of angled blades and spins the shaft
Our own drawing
The diagrams are simplified teaching drawings, not to scale, and the animated engine and games are our own code. Names of historic engines, railways and companies (such as Rocket, Puffing Billy or Big Boy) are used only to describe history; no endorsement by any museum, railway or company is implied. Useless the eraser is the network’s own mascot. Fonts: Bricolage Grotesque, Newsreader and Kalam (SIL Open Font Licence), served from this site.