Appleton's dictionary of machines, mechanics, engine-work, and engineering (1869)
New York, Appleton · leaf 245
ler binds and requires to be moved, the secondary tumbler1) 1>, that takes the pressure, being behind the iron wall I K, which is fixed completely across the lock,prevents the possibility of its being reached through the key-hole, and the first tumblers B B are quitedetached at the time, thereby… … L is the drill pin on which the keys fits; and M M is a revolving ring or curtain, wluch turns round>yith the key, and prevents the possibility of inspecting the interior of the lock through the key-hole;and should this ring be turned to bring the opening upward, the detector plate is…
Mechanical engineering
Internet Archive · Gerstein Library, University of Toronto · Public Domain Mark 1.0. Free to use for anything.
