Scotia, or Canada stone, which is brownish yellow in colour when new, changing to a yellowish grey by use, and wearing away rather quickly. The Washita stone cuts more quickly than a Turkey stone, and also more regularly. Some kinds are of a whitish grey or light buff colour when oiled. The Arkansas stone is compact and white, and finer in grain than the Washita. It wears well and cuts slowly, producing fine edges. Oilstones generally are about 8 in. long, 2 in. wide, and 1 in. thick, a very convenient width being 1½ in. A small oilstone of 4 in. by 1¼ in. is useful for sharpening spokeshaves, and pieces or slips of
Fig. 118.—Oilstone in Plain Case.
stone of various sizes and shapes are required for gouges, router cutters, etc. It is usual to keep an oilstone in a box or case (Fig. 118). Neat's-foot oil or sperm oil commonly is considered best for oilstone use; lard oil containing sufficient paraffin to prevent it going thick in cold weather is also recommended. Many other oils are used for the purpose, but all tend to harden the surface of the stone much more quickly than neat's-foot or sperm. The oil can be kept in a bench oil-can, which will come in generally useful.
Emery Oilstones and Oilstone Substitutes.—Emery oilstones are an American introduction, and are made of Turkish emery, one face being of fine and the other of medium coarse material. They have the advantage over any natural oilstone of being uniform in texture, and of not being brittle. Oilstone substitutes are strips of zinc upon which is sprinkled a little flour emery and oil, this working more quickly than a proper stone, but not giving so finished an edge.
Nails, Screws, and Glue.
Nails.—Nails may be of iron, steel, etc., wrought, cast, cut, or made of wire. Formerly nails were said to be 6-lb., 8-lb., etc., according as 1,000 of the variety weighed that amount—hence now such meaningless terms as sixpenny, eightpenny, and tenpenny nails, in which "penny" is a corruption of "pound." Of the nails commonly used in carpentry and joinery, the cut clasp nail, machine-made from sheet "iron" (probably steel), may be used for almost any purpose, and is not liable to split the work. Rose-head nails have a shank parallel in width, but tapered to a chisel point in thickness; these are made of tough wrought iron, and are used chiefly for field-gates and fencing. Wrought clasp nails resemble the cut clasp, but have sharper points, and are used chiefly in common ledged doors, as they will readily clinch. Oval steel nails are nicely shaped, very tough, and are less likely to split the material than any other kind of nail; slight shallow grooves in the shank increase the holding power. Brads are known in more than one variety. The cut-steel large brad is used in flooring, and does not make such a large hole as a cut nail. The cut-steel small brad is used for general purposes. French nails are of round wire, pointed, and have round, flat heads; they are strong, but their unsightly heads cause their use to be confined to rough work.
Fig. 119.—Square Nail Set or Punch.
The double-pointed nail is intended for dowelling and other purposes.
Nail Sets or Punches.—For punching nail heads below the surface of the work a steel set (Fig. 119) of square or round section is used.
Screws.—The screw nail commonly used for uniting woodwork is known as the wood