Leather: From the Raw Material to the Finished Product

by K. J. Adcock

Naturally, there is in the aggregate a considerable supply of raw hides and skins from other parts of the world in addition to that from the countries specially named, and new sources are being frequently found.

It would be impossible to describe the characteristics of the numerous varieties of hides and skins except in a full-sized text-book, but a brief description of the principal sorts may be given.

Some of the varieties produced in the United Kingdom have already been described. In the main, there is not a great deal of difference in the hides of various breeds, but there is a type of well-grown and stout hides specially suitable for sole and belting leather; this class is known as runts, and these hides are obtained from the Scotch and Hereford breeds of cattle. The Scotch runts from the Highland cattle are more valuable than any other class of hide found in the United Kingdom; unfortunately, the production is small. Irish cattle also yield good hides, but in England the interests of the cattle owner, or feeder, are in conflict with those of the tanner, for the system of artificially fattening cattle with oil cakes tends to make the hides very greasy and weaker in the fibres than those hides from animals which are reared on natural food-stuffs.

This grease is very difficult to remove and reduces the selling value of sole leather by about 2d. per lb. The use of a borax solution for soaking partially removes the grease, while it has been proposed that the pelts should be treated with a solution of hyposulphite of soda just before placing them in the tan liquors. A drawback of the latter process is that a little weight is lost in the finished leather.

The trouble caused by the presence of a large quantity of natural grease is even more pronounced in sheep skins than in cattle hides. Naturally, a sheep arrives at maturity in about two years; but by the modern system of intensive feeding with oily food-stuffs it can be fattened in about ten months. This is obviously a great advantage to the sheep-breeder; in other respects it is an unsatisfactory method, for the mutton is not so well matured, and, therefore, is not so nourishing; it contains too large a proportion of fat, and the skins are very greasy and weak in fibre. The excess of grease does not detract from the value of the wool, and may even be beneficial.

There are several varieties of sheep in the United Kingdom, with widely different characteristics. A fellmonger should have a good knowledge of the skins of various breeds in order to buy the particular sorts that will meet the requirements of his customers, as his business is to separate the wool from the skins and to supply the former to the woollen factories and the latter to the leather-dressers. He has, therefore, to study carefully both the wool and pelt markets. While some breeds of sheep yield fine long wool of bright lustre, others have comparatively short-stapled, and "kempy" wool. Between these two classes, there are numerous grades, and the task of sorting the various qualities of wool in those fellmongeries where several classes of skins are worked is by no means easy. It is a generally accepted axiom that the pelt (i.e., the skin denuded of wool) is weaker in fibre in those skins which yield the finest and best wool. In support of this, the Welsh mountain sheep may be cited. This sheep has short, curly wool, but its skin is tough and strong on the grain. In fact, it is about the only breed suitable for roller leather, which is used in the cotton industry for covering the drawing rollers of spinning-machines. Most of this leather is made in North Wales, whence it is exported to every country where the cotton industry is carried on.

Notable exceptions of the general rule regarding the relative qualities of wool and pelts are found in two or three English varieties, namely: the Lincolns, Leicesters and black-faced Suffolks, which produce both fine wool and large pelts of good quality.

Other useful British breeds are the Southdowns, Devons, Shropshires, Wensleydales, Scotch black-faced, Cotswolds, and Kerrys. Of the imported varieties, the New Zealand and Cape sheep skins are the best. The former, principally merino stock, not only provide very fine wool, but also pelts of choice quality and large pattern. Although the quality of the wool of Australian merino sheep is little, if any, inferior to that of the New Zealand type, the skins are not so good in quality, due, no doubt, to the hotter climate, which is favourable to the breeding of insects and other pests which damage the skins. The Cape sheep provide a skin which is quite different in texture from that of any other breed. It has a certain looseness of texture and softness of grain which make it particularly suitable for the manufacture of glove leather.

South America is another large sheep-breeding country; but the skins of this variety are not largely imported into England, most of them being sent to Mazamet, the great centre of the fellmongering industry in France. Buenos Aires skins are the most favoured of the South American skins, owing to their large size and good substance. Monte Videos are also very fine skins.

Smyrnas and Bagdads are other well-known varieties, but they are generally imported in a rough-tanned condition, or, as it is known technically, "in the crust." Leather-dressers finish them for various purposes, but mainly for boot and shoe lining leather. When properly tanned by the natives, these skins produce a supple finish, especially those of the Smyrna variety. Unfortunately, many lots are merely coloured on the surface with the tan liquor, with the result that they dry hard and tinny; such partially-tanned leather is very difficult to finish and is rarely satisfactory. Even when the tannage is completed elsewhere before finishing them, they never produce such good leather as skins properly tanned in the first instance.