Tanning



In medieval Chester the main industry was leather. There were skinners, tanners, glovers, shoemakers and saddlers in profusion. Local landmarks include "Shoemakers Row" and the "Gloverstone". As well as leather from dairy farming pelts and skins were imported on a huge scale. Both tanned and raw hides were sent from Ireland to Chester, together with tallow used in waterproofing, but skins were considerably more numerous. In 1525-6, for example, Chester received some 2,200 hides, over 13,000 lambskins, 10,200 sheepskins, 2,300 badger pelts, 1,100 calfskins, 640 marten and otter skins, 300 fox skins, 90 goatskins, and 50 hart skins. Alum and oil, used by Glovers and Tawyers to prepare light leathers, also came from Ireland. Prices for skins in the luxury market rose fast between 1500 and 1550, marten tripling in price and otter quadrupling, and Irish skins were sold in London after preparation in Chester. In 1536 Chester was brought into the national customs system for leather and in 1537-8 customs duties were paid on 10,681 tanned hides in five Spanish and five Chester ships. Figures for later years ranged from 700 to 1,600 hides, with Spanish merchants exporting the larger share. The privileges of the various trades and their asssociated guilds were jealously guarded (see: "Charters") - in 1433, the Mayor and Sheriffs of Chester were ordered to find and punish all ‘foreigners’ who used the trade of skinner and shoemaker within the liberties of Chester.

Divisions of trade in the leather industry were fine and complex. The English term Cordwainer, meaning shoemaker, first appeared around 1100. By the late 13th century a distinction grew in England between Cordwainers, who used only alum 'tawed' cordwain, and the other shoemakers who worked with the inferior 'tanned' hides. Cordwainer worked only with new leather, whereas a Cobbler worked with old. Cobblers have always been repairers, frequently prohibited by law from actually making shoes. Some even going as far as collecting worn out footwear, cutting it apart, and remanufacturing cheap shoes entirely form salvaged leather - hence the term "cobbled together" for somerhing made of diverse parts in a possibly rough and ready manner.

History of Leathermaking
The English word for tanning is from medieval Latin "tannāre", derivative of "tannum" (oak bark), from French tan (tanbark), from old-Cornish tann (red oak). Tanning converts the protein (collagen) of the raw hide into a stable material, which will not putrefy and is suitable for a wide variety of purposes. Tanning materials form cross links in the collagen structure and stabilise it against the effects of acids, alkalis, heat, water and the action of micro-organisms.

Historically, this process was considered a noxious or "odoriferous trade" and relegated to the outskirts of towns or even to sub-classes of society. Throughout the early Middle Ages, in countries under Muslim rule (such as Spain), tanning and leather craft remained in Jewish hands because of the low status of the profession. The famous Cordoba leather was exported to North Africa and Europe, including to Chester. The Moors in Cordoba specialised in two trades, the silversmiths and the production of cordovan leather, called 'cordwain' in England. Originally made from the skin of the Mouflon sheep, found in Corsica and Sardinia, this leather was tawed with alum, tanned with sumac and finished with oils to produce leather of unequalled quality. The method was supposedly known only to the Moors. English Crusaders brought home much plunder and loot, including the finest leather the English shoemakers had ever seen. Gradually cordovan leather became the material most in demand for the finest footwear in all of Europe.

Skins typically arrived at the tannery dried stiff and dirty with soil and gore. First, the ancient tanners would soak the skins in water to clean and soften them. Then they would pound and scour the skin to remove any remaining flesh and fat. Next, the tanner needed to remove the hair from the skin. This was done by either soaking the skin in urine, painting it with an alkaline lime mixture, or simply allowing the skin to putrefy for several months then dipping it in a salt solution. After the hairs were loosened, the tanners scraped them off with a knife. Once the hair was removed, the tanners would "bate" (soften) the material by pounding dung into the skin, or soaking the skin in, for example, a solution of animal brains. Bating was a fermentative process which relied on enzymes produced by bacteria found in the dung. Among the kinds of dung commonly used were those of dogs or pigeons. Between the mid-sixteenth and the mid-seventeenth centuries one-fifth of the annual new admissions to the freedom of the city of Chester were leather workers, although later in the seventeenth century the proportion declined. The merchants of Chester exported large quantities of dressed calf skins from the port under licence, claiming (in the Rolls of the Freemen) that "the countrey adjoyneinge [did not afford] anie other commodities transportable." Glovers at Chester in the late sixteenth century could afford to buy leather only in small quantities, "never more than 2os. together at one time," and could not expect to make more than four shillings profit a week.

Economic factors contributed to the decline of the leather industries in Chester. The Chester tanners attempted to take political action to defent their interests in the early 18th Century, when new duties were imposed on tanned and untanned skins and the export of oak bark to Ireland (where a rival leather industry was growing) was depriving the Chester tanners of this important raw-material. In effect, the Chester tanners were struggling against the gonvernments need for revenue and against the economic interests of Irish tanners, the oak bark exporters and British curriers and shoemakers. The Chester tanners had the support of their MP, Peter Shakerley, but all their petitions were rejected and the trade continued to decline.

"Chrome tanning" became attractive after the 1860's. It is effective on skins which will be used for softer, stretchier leathers, such as those found in purses, bags, briefcases, shoes, gloves, boots, jackets, pants, and sandals. Hides which are tanned with minerals are pickled first in an acid and salt mixture. From there, hides are soaked into a chromium-sulfate solution. This process is much faster than vegetable tanning/ The rise of chrome tanning coincided with the clearance of much of the ancient oak forests of Cheshire, which had been the principal source of oak bark used in tanning.

Sources and Links

 * The Leather Crafts in Tudor and Stuart England;
 * The Politics of the People in Eighteenth-Century Britain;
 * The Post-Medieval Period Resource Assessment;