Apr 15, 2021 - Sale 2564

Sale 2564 - Lot 303

Estimate: $ 500 - $ 750
(SCIENCE & ENGINEERING.) Evans' Safety Guard. Illustrated broadside, 12 1/2 x 7 3/4 inches; annotated with a manuscript list of ships, integral blank apparently unevenly excised, horizontal folds. [Pittsburgh, PA?], 1841?

Additional Details

This circular describes a widely-used but controversial invention to avert steam engine explosions. A spindle was inserted into a metal alloy near the hottest part of the boiler. If the temperature reached a certain level, the alloy would melt, and the spindle would release steam. Here the illustrations are accompanied by a detailed key and description, as well as a list of 27 boats built in Pittsburgh which had used the safety guard. 23 more ships are added in manuscript. The inventor was Cadwallader Evans, son of well-known engineer and author Oliver Evans. One in OCLC, at Princeton.