When the stone is sawed to the proper size, the surfaces which are exposed to view, have to be made smooth and even. The tools used by the mason for this purpose consist of iron chisels of different widths, and principally of a sharp-pointed one called a _pointer_; these chisels are struck with a mallet made of a conical-formed lump of hard wood, fixed to a short handle. [Illustration: Stone-Sawyer.] The _pointer_ is used for chipping off the principal roughnesses on the face and edges, and for working the whole face over to bring it level, the workman trying his work by applying a _straight-edge_ occasionally to it. When the front and edges are made _true_, the face is sometimes _tooled_ over, so as to leave regular furrows in it, according to certain forms, by which the different kinds of work are distinguished. But this practice is going out of use, now that soft free-stone is so much employed in building. In old edifices, such as St. Paul’s, Whitehall, &c., &c., the stone will be found to be wrought on its face in the manner alluded to. Stones in buildings are not only fixed with mortar, as bricks are, but are further secured in their places by being clamped together with iron clamps. These are short iron bars, from seven to twelve inches long, one and a half wide, and half an inch thick, according to the size of the stone; the ends of the clamps being turned down a little, to afford a better hold. A channel is cut in the two contiguous stones deep enough for the clamp to lie in, and the ends of the channel are sunk deeper, to receive the turned-down ends of the clamp; when this is put into the channel, molten lead is poured in to fill up the interstices, to keep the clamp in its place, and to prevent it from rusting. From the expense of carrying and working stone, the walls of buildings at a distance from a quarry, such for example as those in London, are seldom now built of solid stone, but a facing of this material is applied only on the external surface of the wall, which is built of brick. This kind of work is called _ashler_ work, and both the brick and stone-work must be executed with considerable care, to enable a wall composed of two materials to preserve its perpendicularity; it being obvious, that if the brick part yielded to the weight, it must, from its construction, do so more than the stone facing, and, therefore, the wall would bend inwards and become crippled.