Gear's illustrated catalogue of wood and iron working machinery (1872)
A.S. Gear, Gear, A. S · Boston : Printed at A.S. Gear's printing office, 62 Sudbury Street · leaf 135
Bourdon, with Lanes Improvement. The Allen Gauge.The principle of the Allens Patent Steam Gauge is perfectly simple, and entirely free from the objectionswhich exist in every other protected Spring Gapge in use. The steam acts upon a tapered volute, or coiled steelspring, which is protected by an…
