ClipArt ETC
"The simple outline of the atmospheric engine. Its mode of operation is as follows. Steam is admitted from the boiler into the cylinder, through the tube l, by means of a regulating cock, e, which is worked by a handle outside the boiler; the pressure of the atmosphere above the piston being thus balanced by the force of the steam beneath it, the extremity of the lever beam to whch the piston is attached is elevated by proportionate weights, w, attached to the pump-rod, and the piston is drawn to the top of the cylinder, the other extremity of the beam being depressed." —Comstock, 1850

Newcomens Engine

"The simple outline of the atmospheric engine. Its mode of operation is as follows. Steam is admitted…