This section is from the book "Spons' Mechanics' Own Book: A Manual For Handicraftsmen And Amateurs", by Edward Spon. Also available from Amazon: Spons' Mechanics' Own Book.
These differ from squares, in that they are destined for marking lines at angles to the first side of the work, but not at right angles. Examples are shown in the annexed illustrations. Fig. 256 is an ordinary angle bevel; Fig. 257 is an improved metallic frame sliding bevel; and Fig. 25S is a boat-builder's bevel with 2 brass blades. The bevel is used in precisely the same manner as the try square. A very useful bevel protractor, with a sliding arm and half circle divided into degrees, is sold by Churchills.