from The Century Dictionary and Cyclopedia
- n. An attachment to a boiler to indicate the pressure of steam; a pressure-gage.
Sorry, no etymologies found.
He kept his eyes on the steam-gage most of the time, and the minute the quivering finger began to drop, showing reduced pressure, he opened the door to the glowing furnace and fed the fire.
Parker turned and consulted his steam-gage and water indicator.