The most important machines outside the working cylinder type are the splitter, and the glazer. There are several kinds of splitting machines, but the band-knife machine (Fig. 7) is the most largely used. This is a veritable triumph of the engineer's art, for it is possible to make five or six layers, all about the same size, out of one hide, although leather is only split once or twice as a rule. Of course, sole, belting, and other thick leathers are not usually split. The invention of the belt-knife splitting machine revolutionised the leather trade, and there would undoubtedly have been a great shortage of leather without it. Formerly, all the levelling and reducing of substance was done by paring off quite small pieces with the shaving knife (Fig. 8), a difficult and laborious work. These parings were only suitable for pulping and compressing into leather board; but now the flesh splits removed by the machine can be curried, enamelled, printed, or rolled to make serviceable leathers, although, of course, not nearly so good in quality as the top or grain split. The main working part of the splitting machine is an endless steel knife which passes round two wheels placed at opposite ends of the machine. The leather is drawn to the knife through two rollers, of which the lower one is in sections to allow very thick parts of the hide to pass through the machine. It would need a large volume to describe in detail all the different machines used in the leather trade; the constructional details of only one machine can be given, and, in view of its importance, the shaver is selected. Reproductions of other machines will appear in succeeding chapters. [Illustration: FIG. 8 SHAVING KNIFE] Nearly every leather trades' engineer constructs shaving machines, but the Howard-Smith is described here, not because it is the most popular (unfortunately there is a decided preference for low-priced machines), but because it is one of the best from an engineering point of view, and because several improvements are embodied in its construction. [Illustration: FIG. 9 SHAVING LEATHER (Old method)] This machine consists of nearly one hundred parts and each is made of the best material available. The advantage of this is obvious when the question of repairs is fully considered. The first Howard-Smith machine made has been running more than four years, and has not cost the owner a penny for repairs, beyond, of course, the expense of replacing the blades of the working cylinders; whereas it is no uncommon occurrence for a cheap machine to be thrown on the scrap heap after a few years' wear. It is always advisable, therefore, to buy machinery of the best grade. [Illustration: FIG. 10 DRAWING OF SHAVING MACHINE]