Classical Studies 2700B

LEATHER

[Note: I shall be moving to another office in Talbot College during this coming week (from TC 431 to 429). It may happen on Monday or Tuesday and I shall announce in class on Tuesday whether or not it has happened. CLM]

Terminology: pelts of larger animals referred to as “hides”; with smaller animals (plus reptiles, birds and fish) “skins”. Skins and hides have three layers: outer layer is epidermis; middle layer (true skin) is corium or derma; innermost layer is flesh or adipose tissue.

The epidermis is thin but includes hair/wool, plus nails, scales, horns, hooves; all of this is removed by soaking and scraping (process is referred to as “scudding”). Corium/derma consists of felt-like mass of fibres held together by a fine filament network(“reticular tissue”); remains of epidermis on surface of corium/derma (hair follicles, sweat ducts, old scars, etc.) produce “grain” of leather (though this can be done artificially by stamping; e.g., “morocco” leather, originally goatskin tanned in Morocco by means of Sumac, produced from a type of tree native to S. Europe-N. Africa). Flesh/adipose tissue has membrane-like character and is removed before tanning happens by process called “fleshing”. Additional point: leather is an artificial product; raw skin, when dry, is hard and rough, containing a gelatin-like substance called “collagen” (used in cosmetic surgery today). Skin can easily be softened in water, but it is then liable to rapid putrefaction (it can also be dissolved in hot water to make glue or size). The process of “tanning” results in a product that can be hard (as with saddle-leather) or very soft (as in some types of clothing); and it is “imputrescible”.

So, there are three main steps in production of leather: (a) preparation for tanning (above); (b) actual tanning—use of certain chemicals to make corium/derma imputrescible and water-resistant; and (c) finishing—including rolling dyeing, embossing, glazing, and making waterproof by means of grease-based product (such as dubbin).

Basically three tanning processes used in antiquity:

a) Vegetable tanning: uses tannin (or tannic acid), present in many kinds of vegetable matter. In W. Europe oak-bark, oak-wood and oak-galls (caused by insect eggs in dwarf oak) were most widely used, from Palaeolithic age to 15^th century AD; in East and in N. Africa Sumac was most widely used.

b) Mineral tanning (a.k.a. tawing): corium is immersed in strong solution of alum (double sulphate of aluminum and potassium) and salt (2:1); known in Middle East from early times (tawed objects found in pre-Dynastic tombs in Egypt). Finished product not as satisfactory as those from vegetable tanning.

a) Oil tanning (a.k.a. chamoising; how do you pronounce “chamois”?): rubbing of oils into skins to make them supple and water-resistant; but this is not true tanning, though quite widely used in antiquity.

Two final technical points: tanning was an occupation somewhat looked down on at almost all times up to present; reasons for this. Tanners, however, could become very rich: exx. in Athens of Cleon and Anytus; also in central Greece there were two places called Locris: the W. one, on the Gulf of Corinth, was called “Ozolis” (“stinking”) because of poorly-tanned clothing worn by people there in early times. Also, the term tannin comes from Celtic languages, where “tann” refers to the oak-tree; in Germanic languages “tann” refers to the spruce-fir (cf. the German carol “O Tannenbaum”).

Slides illustrating shoe-making, both Greek and Roman; leather decoration including cutting, heating, use of metal studs, and moulding; discussion of saddles in ancient times (both shabrak and saddles with horns); dyeing and painting. Finally, ancient Roman leather bikinis!!