Chapter VI: Patents for Tanning

The following described processes for Tanning have been patented at different periods since 1849.

The first may be denominated Hibbard’s patent, issued to Mr. Hibbard, of Henrietta, N. Y.

A patent for a modified process in tanning leather, which is specially applicable to light skins, but may be used in all kinds of tanning.

The gist of the invention consists first, in a modified process of unhairing the skins, by a composition of lime, potash and salt, by which the process is very much shortened; and secondly, by combining what is called the process of _plumping_ with that of _tanning_. It is alleged by the patentee that the process of plumping, which consists in the use of acids, to open the pores of the skins, is like that of rising dough by yeast; namely, that after the pores have once been fairly opened, if the tanning process is not commenced immediately, they will soon begin to close; as dough once raised, if not transferred at the proper time to the oven to be baked, will fall, and an inferior bread will be the result.

The process of tanning therefore, as set forth by the inventor, consists in the combination of the plumping and the tanning process, so that as soon as the acids have acted to open the pores of the skins, the tannin present in the liquor, shall enter and perform its part in the operation.

The next may be described as Towle’s process, or improvement in tanning. Issued Oct. 7, 1851.

What I claim as my invention or discovery, as a new and useful improvement, and desire to secure by letters patent, is the use of arsenic or arsenious acid, substantially in the manner and for the purposes herein set forth; the peculiar properties of arsenic, by which it tends to suspend the natural tendency of the animal fibre to decomposition upon the extinction of animal life, are well known, and of course they are not patentable; but their application to the processes of tanning, and otherwise preparing skins and hides for useful purposes, by which they are rendered stronger and more durable, is believed not to have been heretofore known and used.

I do not, therefore, intend to limit my claim to any particular mode or period of using the article; but I shall apply it in such form, or in such strength of solution, as the nature of the case may require, to effect the objects named. Workmen should guard against the absorption of the poisonous qualities of the arsenic, while immersing or handling the skins in the liquor, by using tools or wearing India-rubber gloves. After the skins are taken out of the liquor and rinsed thoroughly, the danger ceases.

N. C. TOWLE.

A patent for the following method of tanning was issued March 22, 1853, to Roswell Enos & Bela T. Hunt, of St. Charles, Ill.

We claim the process of tanning with the use of lime, salt, bran, sumac, and cutch, or any other tanning in room of cutch, substantially in the manner described, whereby we commence tanning, at the same time that we commence reducing, as the salt and bran overpowers the lime, the tan takes the place of the lime, and converts the hide into more perfect leather, and in less time than can be made in any other way.

Hides are not liable to get damaged by our process, as we do not use an article that is injurious to leather.

It is not on the materials used that we claim letters patent, but on the manner of applying them to the hide, as set forth.

The next is to Roswell Enos. Improvement in the process of tanning leather for soles. Patented July 18, 1854.

The improvement and claim consist in commencing the tanning operation upon the sides, by the use of a salted infusion of sumac, and then completing said tanning operation by the repeated use of the strong oak or hemlock bark liquor, substantially as set forth. It is stated that solid sole leather may be produced by this process in an unusually short time.