This joint is similar to notching, only instead of the notch being carried right through, as in Fig. 14 a part or cog is left near the centre, as shown at Fig. 18, or to one side as in Fig. 19. The only difference in making this joint is that the sides have to be mostly cut down with the chisel (Fig. 20), as the saw can only be applied to do a small part of the work in this instance.