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.
To an amateur, dovetailing is no easy matter, when beauty and strength of joint are aimed at. The pins are less difficult to make than the dovetails, but they must be truly vertical. The real trouble is with the dovetails, as they are on arbitrary lines. Much assistance may be got from the employment of a fret sawing machine. This should either have a wooden table, or its iron table must be covered with a wooden one 3/4 in. thick. On this are scribed, 1/2 in. apart, parallel lines at right angles to the saw front; about 1/3 in. in front of it is grooved out 1/2 in. deep between the lines. Fitted to slide in this groove, 2 pieces of hard wood are prepared: one carries, at right angles, a sloping block as a guide for cutting the pins, and the other a similar guide for the dovetails. Screws can be used to hold the guides in place. A slot is cut through the table (or false table, as the case may be) to let the saw work. The guides just described are used to regulate and govern the direction of the saw so that it shall not deviate from the lines marked out.