Leather is made by treating the hides of various animals such as the calf, cow and horse. These are the principal animals from which we obtain hides for making leather to make shoes. Before the hides are fit for making shoes, they must be taken to a tannery where they are prepared and tanned.
In viewing a tannery, we enter first the enormous hide house. It is long, damp and dark. Here the hides are collected from all over the world and stored, awaiting their turn for tanning. We follow a small car of these hides into the beamhouse. We see the hides loaded into a vat. They are soaked, resoaked, softened and split into sides. This operation, while simple, holds your attention longer perhaps than any of the others. Several hides after being softened are thrown over a sort of saw-horse, the lot number is stamped on the hide in such a manner that it appears on each side after being split. With an unusually long bladed knife the workman quickly cuts down through the center and the hides which are now called sides, fall to the floor. They are next hooked together and pass on through vat after vat of lime solution which loosens the hair and superfluous flesh. At the end of this long chain of vats, we see the sides awaiting their turn at the first unhairing machine, where all the hair is removed and then to the fleshing machine, where the flesh is taken off and the sides are again loaded in a car and pass on to the tanyard.
HOW THE HIDES ARE TREATED
THE TAN YARD
We resume our travels, following a car of sides from the beamhouse to the sole leather tanyard. There are about 40 operations in the tanning of sole leather, requiring about 100 days to produce first quality leather. In the tanyard, we see more than 500 vats, each holding 300 sides, weighing about 23 pounds apiece. Each vat contains about 3000 gallons of liquor at an approximate cost of $100 a vat. Here we see the sides slipped over sticks and placed in vats six feet deep, where they receive the tanning, the real tanning process which preserves the fibers giving the leather its life and long wearing qualities.
From the tanyard we go to the big wringers where the liquor is wrung out, the hides are milled, dried and loaded on cars for the drying loft, where they are allowed to dry or season preparatory to rolling. This long building is sectioned off every 50 feet into chambers, where the hides are hung in the same manner as in the vats. The temperature of each room is changed from the outside temperature to a heat of 115 degrees, at which temperature the hides are dried and are ready for rolling.
Man rolling a hideIn the rolling room, we see an operation requiring skill and quickness of eye. The rollers pass to and fro over the side, which is now hard and stiff, with a pressure of 300 tons. This rolling or finishing gives it a high polish and we see a beautiful side of sole leather, weighing from 18 to 25 pounds.
HOW UPPER SHOE LEATHER IS TANNED
Men handling hides near rolling drumsIn the upper leather tannery we see the various operations preparatory to the actual operation of tanning the hide, about the same as in the sole leather tannery, with this difference: Upper leather in this tannery is generally chrome tanned, a process requiring 30 days and instead of vats sunken in the ground we see huge rolling drums revolving at a rapid rate. This process is the most up-to-date method and absolutely insures the wearing qualities of the leather. This leather is very tough, yet is just as soft and pliable as glove leather and as comfortable to the feet. It does not harden with age, nor does it stiffen after being wet.
UNHAIRING MACHINE
One of the most interesting sight while going through the tanneries is the process of disposing of waste materials, such as hair, fleshings and the sediments from the lime and sulphur vats.
The hair is separated into white, brown and black colors, each color taking its turn through the huge mill or gin where the hair is dried and afterwards baled. The brown and black are sold to plasterers. Those who purchase the white often mix it with wool and use it for making many useful articles.
The fleshings and trimmings are sold to manufacturers of glue.