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Glossary
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Cabretta Leather
A wrongly named hair sheep. When the Portuguese first went to Brazil they mistook the indigenous hairsheep for goats and called them cabrettas (kids). The skins were exported to the USA by the Blue Funnel Line (later the Booth Group) and the name cabretta stayed with them. Now all hairsheep skins have taken the generic name cabretta. Much used in footwear leather and sport glove leather.
California Banknotes
In "Two Years Before the Mast" (15) Richard Henry Dana describes how he sailed from Boston to California in 1834 to collect hides. He explains how hides are dried and loaded onto the ships before returning to the East Coast. Since California had nothing else of wealth at that time the dried hides were known as "California Banknotes". "The hides are brought down dry, or they will not be received. When taken from the animal they have holes cut in the ends, and are staked out, and thus dried in the sun without shrinking. They are then doubled once, lengthwise, with the hair side usually in, and sent down upon mules or in carts, and piled above high-water mark: and then we take them upon our heads, one at a time, or two, if they are small, and wade out with them and through them into the boat."
Camar
Widespread caste in northern India whose hereditary occupation is tanning leather; the name is derived from the Sanskrit word carmakara, or "skin worker." The more than 150 subcastes are characterized by well-organized panchayats (governing councils). Because their work obliged them to handle dead animals, the Camars have suffered from the stigma of being considered a very polluted caste. (From encyclopaedia Britannica)
Carding Leather
A special type of side leather used on the cards of cotton machinery. The leather lies flat against the beds of the cards, the teeth being forced through. (11)
Chamois leather
A soft leather originally made from the skins of the Alpine antelope known as the chamois but at the present time from the fleshers of sheepskins. Certain grades used to be used in gloves and fancy articles but the staple employment is for cleaning and polishing, primarily automobile. (11) Chamois is characterised by an ability to absorb at least three times its own weight of water.
Shoemakers, but unlike cordwainers they work with old leather. Cobblers are essentially repairers.
Combing leather
The name applied to the leather used on the combing rolls of cotton machinery and manufactured of calfskin or side leather. (11)
Conditioning
When leather is dried after retanning, dyeing and fatliquoring the fibres tend to stick together and the leather is hard. The fibres are separated and the leather softened by staking. Staking is best done at about 18% humidity and so a little humidity has to be put into the dry leather. This is most commonly done by a water spray and then piling the leather long enough for the moisture to even out. Adjusting the moisture content before staking in this way is called conditioning.
Cordovan
The
shell of a horsehide, often tanned with a sulphur tannage. As such it was
a soft vegetable tanned leather first made in Cordoba in Spain, and followed
by goat, sheep and pigskin leathers with a similar formula. Cordovan leather
has good wearing characteristics, and is non porous. The horse product still
tends to be called "shell cordoban leather".
Cordovan Leather
Developed in Spain in the 8th century, when the Moors arrived in Spain. Made from the skin of the mouflon (Ovis Musimom). This hair sheep now only survives in Corsica and Sardinia. It was tanned with alum and later with alum and sumac. (Koninklijke Bibliotheek says sumac was not introduced until the 15th century). Best brilliant scarlet type was tawed with alum and dyed with kermes. (3, 22)
Cordwainers
From Cordovan leather. At first made many types of leather articles. In Middle Ages specialised in Shoes. Cordwainer is from the French word "cordonnier" and came to England in 1066 with the Norman Invasion. After Cordoba fell in the 12th century English Crusaders brought back this alum-tanned goatskin. It was considered the highest quality shoe leather in Europe. Cordwainers work only with new leathers.
Corrected Grain
Chrome tanned side leather which is buffed with emery paper on the grain side to remove defects and then has a plastic resin and pigment finish built up on the leather. Used for shoe upper leather.
Crupp leather
A semicircular portion of leather taken from the butt of stuffed vegetable tanned horse hide. (1)
Crust
Leather dried after tanning. Since chrome leather dried immediately after tannage will go hard, change charge and become difficult to rewet, this drying normally takes place after a basic retanning and fatliquoring. Leather is frequently traded world wide in this state, although tanners normally prefer to buy wet blue or pickle which gives them more flexibility of processing.
Currying
A term practically equivalent to dressing and finishing, but confined chiefly to heavy leather (Latin corredare, to prepare or dress). (11)
Deliming
A process preparatory to tanning proper to reduce the swollen and rigid fibres of a hide or skin after liming. (11)
Dongola Tannage
The first successful thinking on water stable leathers. Since the Egyptian times we had alum tanning which was soft, but had no resistance to water, and veg tanning was more resistant but was very hard. a. A vegetable and alum tannage developed in Gloversville, New York, in the 1860's to compete with the expensive kid tannage for gloves. Used hair sheep. Dongola is a town in the Sudan, and there is a breed of hair sheep named after it. "Dongola, strictly speaking, is alum, salt, and gambier only, used together in one solution. Dongola is especially applied to glazed and dull kid. For full dongola the process is commenced in very weak gambier liquor, with the full proportion of alum and salt, and the gambier is gradually strengthened. Dull dongola is ironed like kid in the finish. It is said to be sometimes glazed with a blood seasoning, and then dulled by a mixture of soap and oil, followed by slating with a smooth round -edged slicker, but it is generally sized". (5)
b. Dongola tannage.- gambier, alum, and salt make what is known as dongola leather. There are many modifications of this process. Fine leather is made by tanning the skins first in gambier or quebracho liquor, and then giving them an alum and salt re-tannage. For 200 average skins, a mixture is prepared of 5lb. of alum, 9lb. of salt, 24lb of flour, 10lb. of egg-yokes, or a corresponding quantity of sulphonated oil, and 8 to 10 gallons of water. The flour is made into paste with cold water. The alum and salt are dissolved in part of the water, and the flour paste is slowly stirred into the solution. The oil or the egg-yoke mixed with warm water is next added, and the whole mixture is thoroughly stirred. The tanned skins are drummed with this mixture one hour, then dried, colored and finished, thus making soft, durable leather.
This mixture may also be used on untanned skins as come from the bate or drench. They should be drummed with it, dried, kept in crust for some time, then wet-back and tanned with chrome liquor, the result being soft durable leather.
The combination tannage of gambier, alum, and salt can also be applied in the following manner: The bated and washed skins are placed in gambier liquor in a paddle. From 3 to 5lb. of gambier are used for one dozen skins. After they have started to absorb the gambier, from 8 to 16 oz. of alum and 8 oz. of salt are added to the liquor, for each dozen skins, and the paddling is continued until the tannage is complete, which takes 18 to 36 hours. The leather is then washed in warm water to remove the adhering tan, next fatliquored with acid fat-liquor, dried, wet-back, colored, dried again, and finished. After the alum and salt have been added it is customary to put the skins, together with the tanning liquor, into a drum and run them for a few hours or until thoroughly tanned. Some soluble oil may also be added to the liquor and applied to the leather toward the end of the tanning process. Excellent leather is also made by taking the skins out of the gambier liquor when they are well struck through, striking them out and then drumming them with a paste of water, flour, alum, salt, and either egg-yoke or soluble oil, drying and then coloring them with a basic dye and titanium-potassium oxalate.
The color of the leather can be modified by adding a solution of fustic or other dyewood to the gambier liquor, and the entire process may be reversed. The skins may be first drummed with alum and salt and then tanned with gambier. Heavy skins may be tanned with gambier, alum, and salt. After the leather is dry, it can be colored with acid or basic dies: and, if not fatliquored immediately after tanning, drummed with acid fatliquor or with an emulsion of oil and soap, staked and finished. (12)
Drenching
A process for reducing the plumped fibres of a hide or skin. It accomplishes approximately the same purpose as bating and basically in the same way - that is, through soaking in a fermenting solution. Some authorities, however,, restrict the term bating to the process using ferments of manures and the term drenching to that using damp sawdust, bran, middlings, or a solution of lactic acid or some other chemical having a similar action. (11)
Drums
The collective term for the rotary vessel in which many processes of tanning are now carried out. (11)