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.
There are 3 kinds of gauge used in carpentry, known respectively as the "marking," the "cutting," and the "mortice" gauge. They are outlined in the annexed illustrations. Fig. 252 is a cutting gauge having the head faced with brass; Fig. 253 is an improved form of cutting gauge; Fig. 251 is a thumb or turn-screw screw-slide mortice gauge; Fig. 255 is an improved mortice gauge with improved stem. The marking gauge has a shank about 9 in. long with a head or block to slide along it; a spike is inserted near the end of the shank, and the movable head is fixed at any required distance from the spike by a screw or wedge; its use is to make a mark on the wood parallel to a previously straightened edge, along which edge the gauge is guided; for dressing up several pieces of wood to exactly the same breadth this gauge is eminently useful. The cutting gauge is similarly composed of a shank and a head, but the spike is replaced by a thin steel plate, passing through the shank and secured by a screw, and sharpened on one edge so as to be capable of making a cut either with or across the grain; its main applications are for gauging dovetailed work and cutting veneers to breadth.
The mortice gauge resembles the others in having a shank (about 6 in. long) and a movable brass-shod head, but it has 2 spikes, one fixed and the other arranged to be adjusted by means of a screw at varying distances from the first; it is used for gauging mortice and tenon work. Gauges are generally made of beech, and the shank is often termed the "strig"; compound gauges are now made, consisting of marking and cutting, or marking and mortice appliances combined in one tool. Prices vary from 3d. to 10s., according to finish. In using the gauge, the marking point is first adjusted to the correct distance, then secured by turning the screw, and the mark is made when required by holding the head of the gauge firmly against the edge which forms the basis of the new lines, with the marker resting on the surface to be marked, and passing the instrument to and fro.