Friday, June 20, 2014

Leather tanning - Medieval to Edwardian

Medieval tanner
In need of shoes, gloves, armour, bottles, saddles, harnesses, bellows, sheaths, or scabbards? In the Middle Ages, you would rely on leather workers in a sequence that ran from husbandman to butcher, skinner, and fellmonger. Leather 'workers' included skinners, tanners, curriers, and specialist leather artisans, such as saddlers. (Detailed description of leather-working techniques here.)

Tanners enjoyed the exclusive right to purchase cow hides from butchers. The lighter, smaller skins of sheep, goat, pig, and deer were handled by fellmongers and preserved by tawers (also known as a tawyers or whittawers).


Medieval furrier
In tawing, the hide was soaked in an aqueous solution containing potash alum and salt. Sometimes egg yolk and flour were added to improve the product. Strictly speaking, not having been tanned, a tawed skin is not leather, and is putrescible when wet.

Because horns and hooves had no value to a butcher, they often left them attached to the skins. Where the tanner discarded horn cores and hooves, their remains are a sign that a pit was associated with a tannery.

Horners valued the outer layer of the horn. So, the archaeological remains of tanneries typically include pits where horn cores and hooves have been discarded along with scraps of leather (1º, 2º, 3º). However, glue could made by boiling scraps of leather, adding to the stench of the tanning operation.

Of interest: 13th century cat- and goat-hide shop excavated in England.

Making parchment: video.

Click on images to enlarge.

View of medieval tanning pits - wood-lined trenches and pits
in scale model of Birmingham, England around 1296 CE.

Tanner scraping hides
close-up of lower centre section of image above.

View of medieval tanning pits from different angle
scale model of Birmingham, England around 1296 CE.

As the model shows, tanners needed access to water, which they necessarily contaminated with the chemicals and byproducts of their foul-smelling trade.

Take a video tour of the model of medieval Birmingham (tanning pits at 2m 35s, new window)



The following summary of the tanning process is adapted from here.

After removing the horns and hooves, and trimming unusable portions of the hide (belly, areas around head and legs, udders, and hide edges), the tanner washed blood, dung, and dirt from the hide.

Next, fat, hair, and flesh were removedusually by immersion in a solution of lime or urine. (In sufficiently warm conditions, the hide could be sprinkled with urine and folded hair-side inward to encourage rotting of the hair follicles.)

After treatment, loosened hair was scraped from the hide with a blunt single-edged knife, and flesh was removed with a sharper, double-edged knife.

After rewashing, the hide was de-limed and and softened by one of two alternate processes:
a) an alkali-rich process of immersion in warm dog dung or bird droppings
b) drenching in a solution of barley or rye in stale beer or urine

The hides were washed again, then agitated in a solution of crushed oak bark. After being layered with ground bark, the hides were transferred to a pit filled with a weak tanning solution. Later, they would be moved to a tank containing a high concentration of tannins, in a process that required at least a year to complete.

After 12-18 months soaking in tannin solutions, the tanned hides were rinsed, and smoothed using a two-handled setting pin. Next, they were dried slowly in a dark shed before being sent to a currier, for stretching, shaving, and softening by the application of greases, sometimes brain.





Although oak bark was used extensively in Britain, other plant materials were substituted: fir, white willow (Salix alba), sweet chestnut (Castanea sativa), oak galls, birch, alder, hemlock, heather, and the rhizomes of some ferns.


  • Oak bark contains both types of tannin: catechols and pyrogallols.
  • Catechols are more astringent, act more quickly than pyrogallols, producing leathers of pink, red or dark brown hues: birch, hemlock, alder, and fir bark.
  • Pyrogallols improve leather's wearing properties and resistance to water, so they are favored for sole leather, bookbinding, and upholstery. They produce pale leather varying from creamy or yellowish to light brown: sweet chestnut, oak galls, and oak-wood.


Ancient tanneries—now a tourist attraction—have been discovered beneath the modern city of Nottingham within a system of caves cut into the soft sandstone as houses, cellars and workplaces.

"Nottingham was once known as Tigguo Cobauc meaning Place of Caves and was referred to as such by the Bishop of Sherborne Asser in The Life of King Alfred (893AD)."[w1]

"Two caves cut into the cliff face and opening out to daylight housed the only known underground tannery in Britain. The Pillar Cave was originally cut around 1250 but had been filled in by a rock fall by 1400. Cleared and reopened as part of the tannery in 1500 with circular pits cut to hold barrels. A second cave was also cut with rectangular clay-lined vats. The small size of the vats in these caves indicate that they were probably used for sheep or goats skins rather than cowhide. There was an opening to the River Leen where they would wash the skins in the town's drinking water." [wc]

remains of Medieval tannery
discovered beneath Nottingham, England

City of Caves tannery, Nottingham

City of Caves tannery, Nottingham
Virtual flyround of the caves devoted to tanning:



All you could possibly want to know about the archaeology of leather-working, particularly of footwear in huge pdf file.

Edwardian leather tanning:




Papermaking, Parchment, Manuscripts:






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