Iron nails may be wrought, cast, or cut. Wrought nails may be forged from iron rods, which are now often prepared from plates rolled for the purpose, by slitting them into nail-rods, or split-rods of various sizes and qualities, by means of splitting rollers. For horseshoe nails the best refined iron is used, to allow them to be drawn out fine, and not break in the hoof; wheelwright's nails and hurdle-nails require to be made of a tough fibrous iron. Nails are variously named according to their shapes, or the uses to which they are applied. There are upwards of three hundred varieties of nails, and at least ten different sizes for each variety. A few of the principal forms are as follows:—1. Rose-sharp, a kind much used for coopering, fencing, and other coarse purposes in hard wood. A thinner sort, called fine rose, is used for softer woods, the broad spreading heads serving to hold the work down. 2. The rose with flat or chisel points, which being driven with their edges across the grain, prevent splitting. 3. Clasp-nails, where the heads projecting downwards clasp the fibres. 4. Cloud-nails, with flat circular heads, round shanks, and sharp points, are used for nailing iron-work, &c., to wood. 5. The counter-clout is counter-sunk under the head, and has a chisel point. It is used by wheelwrights and smiths. 6. Fine-dog, and strong or weighty dog nails, are used for nailing down stout iron-work, &c.; they have round shanks and spear-points. 7. The Kent-hurdle, used for nailing and clenching hurdles; gate-nails are similar in form. 8. Rose-clench, much used in ship and boat building; they have square ends, so as to punch out their own holes, and the ends are clenched by hammering, sometimes with the addition of a small diamond-shaped metal plate called a rove. 9. Horse-nails, with counter-sunk heads, so that they may lie flush in the groove made for them in the horse-shoe. 10. Brads and tacks also form useful and numerous varieties of nails. Nails of cast-iron are brittle, but very cheap, and are adapted to such purposes as fixing the lathing of plasterers, nailing up trees to garden walls, nailing stout shoes, boots, &c. Immense quantities of nails are also made by cutting and punching.