Scientific American 20, 17.5.1862
The following extracts on this subject are taken from the Shoe and Leather Reporter: -
Cordovan leather, which takes its name from the city of Cordova, in Spain, and of which the original preparation is attributed to the Moors, is plain, but handsome, with a fine grain, ans similar to the Morocco, which is ordinarily tanned with oak bark, but galls, or sumac. The best kinds, especially the yellow cordovans, are brought from the Levant; those of Spain, France and Hungary are also highly esteemed, and in Germany the cities of Dantzic, Lubec, and Leipzig, enjoy a reputation for like productions. The material used in the manufacture comprises goat skins (both male and female), dog skins, and even hog skins; they are produced every color and quality, but those made of he-goat skins ater the best.
The skins, after having been cleaned and stretched in water, are placed in lime pits; they are the replaced in water for a space of from eight to fifteen days, care being taken to renew it from time to time, and to work the skins by treading upon them with the feet. After a lapse of a fortnight a bath is applied composed of water and the excrements of dogs; the temperature not being higher than that of newdrawn milk; then a second bath, equally composed of water and of wheat bran. Immediately on being taken from the bath the skins are stretched, pressed between two boards, and rubbed with kitchen salt. Then they are immersed in a third bath, prepared of figs and water. Only skins which it is intended to color black are dyed after having been tanned. Black leather is tanned in liquor of the extract of oak bark; that of lighter color must be placed in an ooze made up water and the extracts of sumac and nut galls.
When the operation of tanning is completed, the leather should be withdrawn, taking with it as little moisture as possible, and spread in the sjade, where care should be taken to rub on the bloom with Sesam oil, before the sides can become perfectly dry. After the oil is laid on, the process of drying in the shade may be completed and the skin may be folded on the flesh side. When it is desired to give to the cordovan a rough aspect, the surface may be rubbed up with a dull knife, immediately after spreading.
In many parts of Southern Russia, particularly at Karasubazar, a city of the Crimea, of which the cordovan manufactures enjoy high reputation, wormwood (artemisia amma) is employed to make fast the colors in the leather. If, for example, it is proposed to dye the leather black, a decoction of wormwood is mixed with pulverized cochineal, and then alum is added.
In the Isle of Cyprus, cordovans are dyed red in the following manner: - The skins, generally about fifty at a time, are placed in a fig bath; they are then passed into a strong solution of alum heated to a temperature equivalent to that of fresh milk; they are afterward strung upon poles to drip, and at length stretched, in order to expel as much of the dampness as possible; finally the skins are extended on a table, and after being uniformly stretched the red color is applied with a cottong rag. The coloring matter is prepared by taking ground cochineal and boiling it in soft water in a well-tinned kettle, and during the ebullition five ounces of powdered alum are added for every five ounces of cochineal and the liquor boiled until it has been reduced one-sixth or one-eight by evaporation, when it is passed through a filter. The skins are coated four or five times with this preparaton, and after being placed in the tanning liquor are submitted to the operation of dressing.
In Hungary and in Transylvania, where the manufacturers of cordovans produce goods which are highly esteemed for their quality, the red c olor is laid on in a different manner. When the skins have been properly prepared for the process, they are fastened together by couples in the form of bags, care being always taken to place the sides to be colored within and facing each other, and to leave but one opening. Into this opening the warm coloring matter is poured. The mouth of teh bag is then tied, and if the color does not readily penetrate all parts of the skins and unite with them, they are agitated or rolled around.