Of the wrought, or forged iron nails, there are about 300 sorts, the forms of which are known to the trade by certain specific names, which, for the most part, express the uses to Which they are applied ; as hurdle, pail, deck, scupper, mop, &c ; but there are others whose applications are so general that they are distinguished by certain technical names, expressive of their form ; thus— rose, clasp, diamond, &c. explain the form of their heads, and fiat, sharp, spear, &c. their points. The thickness of any specified form is expressed by the terms fine, bastard, strong. The length of some kinds of nails is directly expressed by their lineal measure ; but their length is more usually comprehended by the number of pounds or ounces a thousand of them weigh. Thus the .simple denomination ' 7 lb. rose," implies a rose-headed nail with a sharp point, weighing about 7 lbs. to the thousand, and measuring about 14 inch in length. Now rose nails are made from li to 40 lbs. per thousand ; in all, about thirty different sizes ; and taking the various sizes of other nails (which are not so numerous), we may compute the average number of sizes of each sort at 10, which, multiplied by 300, the number of sorts before mentioned, makes 3000 distinctive names to nails, all of which are immediately and precisely understood by persons engaged in the trade. The terms employed by retailers, of fourpenny, sixpenny, tenpenny, &c., are very undefined as respects the kind, as well as the precise size, varying with the locality wherein_they are sold. To enter into a detailed description of all the varieties we have named would be tedious and uninteresting to the generality of readers; but impressed with the universal utility of mere information than we have already given, we shall proceed to iteman a very condensed and s "c view of their peculiarities and uses.
It having been ex ta 'tied how the various sizes and thicknesses are distin guished, it will only necessary to show the principal distinguishing forms, without regard to actual dimensions. For convenience, therefore, the several kinds delineated in the following engravings are represented as of one sins; and the words printed above and under each, are their proper names.
The first described kind, roes-sktop, are very extensively, and almost univer• sally, used for coopering, fencing, and a at variety of coarse purpose; in which hard wood, such as oak and beech, are used. There is, however, a thinner sort, called fine-rose, of which prodigious quantities are sent to Canada and other parts, which are used in pine and other soft woods, their broad spreading heads being calculated to hold the work down. The rose, with flat or chisel points, are employed in preference to the sharp, where the wood is in danger of being split by the driving in of the sharp points, which act as wedges, while those with fiat points being driven with their edges across the grain, prevent the splitting effect, and hold faster. For these reasons spikes are uniformly made with flat points, from 4 to 12 inches in length, unless ordered to the contrary, for the Brasil market, or other parts of the world, where they may be required for ranch harder woods than any of our own country.
Of the third sort, clasp, there are three distinct thicknesees,--fine, bastard, and strong ; and of each numerous sires. These nails are those commonly toed by the London and other house-carpenters, in deal and similar woods ; their heads are made projecting downwards, so that when they are driven home Rush, their heads stick into the wood and clasp it together, thus checking, to a certain extent, any disposition in the wood to split open; their heads are, in smooth work, driven below the surface, so as afterwards to admit a plane over them.
Of the fourth sort, clot[, there are, also, three thicknesses of the form of that shown ; namely, fine, bastard, and strong; besides numerous sizes. They are much used for nailing iron work, and various substances to wood: they have a flat circular head, round shanks, and sharp points.
There is, however, another kind of clout, extensively used by wheelwrights and smiths, called esarder-elord, the form of which is delineated in the fifth Illustration, which shows that they have counter-sinks under their heads, and chisel points ; they are usually made of tough iron, to bear the battering they receive in nailing down the stout iron work for which they are designed : they are made from 1 inch up to 4 inches in length, and of any required thickness.
The sixth figure of the foregoing sketches, is denominated ifne-dog, in contra distinction to Wong, or unigiardeg, the difference being merely in their propor tionate thickness; these are made from 1 to 5 incheslong, and are used for similar ripens to the last-mentioned, es well as others, where the heads (whin are very sad, and slightly countersunk) are not required to lie flush with the work; dick shanks are round drawn, and their points speared, which adapts them for piercing and clenching well.
The seventh nail is called from having been first used in tent of that peculiar form: has a broad, thinnish rose-head, a clean-drawn, fiat shank, a geed near-point, well adapted for nailing and ()leaching the oaken bars of hurdles together. There are several kinds of hurdle-nails differing from these, but in points an immaterial as not to require notice in this article. Gate nails, which are nearly allied to them, are similar in form, but are usually made stouter: they are made of various lengths.
The eighth of the foregoing figures, row-clench, is a class used for ship and boat building, of which there are several varieties, and numerous sizes. For Ile femur purpose they are much employed in nailing on the wood sheathing, which is soft, and liable to split, unless bored ; and as the nails have no points, the ends being left square, they punch out their own holes, driving a por tion of the wood before them, hold very fast, and render boring unnecessary. For the latter reasons clench-naila are now extensively used in the making of paskinipeases and boxes, it being found, by experience, that this form holds much firmer when driven in the direction of the grain of the wood, than or pointed nails. The term clench is, however, derived from the mode them in boat-building, in which they are clenched, either by bat. taring down the extremiq with the hammer, or, preferably, by placing over the extremity a little diamond-shaped plate of metal, as shown in the drawing, and called a rove, and riveting the end of the clench-nail down upon it, which draws the planks, ita of the boat very firmly and durably together. We are surprised that this simple, cheap, and admirable mode of fastening, should be almost wholly confined to boat•building.