Rubbing
Before this leather can be cut into sole leather it has to be again dried and properly edged to secure the best results.
Boarding Room
Bark-tanned leather that is used for upper stock in shoes is tanned practically the same way as the bark sole leather, except lighter hides are used and the finishing processes are of a nature to make it softer and smoother.
The above tannage is what is called vegetable tannage. There is also a tannage made from minerals that is called chrome. This is used mostly in tanning soft, glovey upper leather, which when finished makes a very tough yet soft and pliable leather for footwear.
Ninety to one hundred days are required to tan bark leathers, while the chrome tannage is very quick and on the average requires only about three weeks.
The brilliant smooth surface of patent, enameled, lacquered, varnished or japanned leather is due to the mode of finishing by stretching the tanned hides on wooden frames and applying successive coats of varnish, each coat being dried and rubbed smooth with pumice stone. There is also a process called “tawing,” which is employed chiefly in the preparation of the skins of sheep, lambs, goats and kids. In this process the skins are steeped in a bath of alum, salt and other substances, and they are also sometimes soaked in fish-oil. The more delicate leathers are treated in this manner, those especially which are used for wash-leathers, kid gloves, etc.
Measuring