Tumblers

One who tumbles; one who plays tricks by various motions of the body; an acrobat.

A movable obstruction in a lock, consisting of a lever, latch, wheel, slide, or the like, which must be adjusted to a particular position by a key or other means before the bolt can be thrown in locking or unlocking.

A rotating device for smoothing and polishing rough objects, placed inside it, on relatively small parts.

A piece attached to, or forming part of, the hammer of a gunlock, upon which the mainspring acts and in which are the notches for sear point to enter.