Examples from the Web for thumbscrew
A painted target, arranged with a slide to be moved up and down on this staff, and held by a thumbscrew, will be found useful.Farm drainage|Henry Flagg French
The thumbscrew would extort a confession from a dead man; and the rack—well, that is something inconceivably devilish.Nasby in Exile|David R. Locke
The small fitting under the gasoline tank has a thumbscrew shutoff and a glass-sight feed tube, leading to the carburetor.
The valve should be of the "screw-down" pattern, either with a thumbscrew, wheel and spindle, or a key.The Turkish Bath|Robert Owen Allsop
The thumbscrew is to be adjusted so that the free end of "F" will rest against it in a temperature of 70 Fahr.Rules and Practice for Adjusting Watches|Walter J. Kleinlein