the skin of several sorts of beasts dressed and prepared for the use of various manufactur- ers, whose business it is to make them up.
Dyeing of Leather, Skins, &c. Blue is given by steeping the subject a day in urine and indigo, then boiling it with alum; or it may be given by tempering the indigo with red wine, and washing the skins there- with. Red is given by washing the skins, and laying them two hours in galls, then wringing them out, dip- ping them in a liquor made with lignum, alum, and verdigriss in water; and lastly, in dye made of Bra- zil wood, boiled with ley. Purple is given by wetting the skins with a solution of roche alum in warm water; and, when dry again, rubbing them with the hand with a decoction of logwood in colder. Green is given by smearing the skin with sap-green and alum-water boiled. Dark green is also given with steel filings and sal ammoniac steeped in urine till soft, then smeared over the skin; which is to be dried in the shade. Sky colour is given with indigo steeped in boiling water, and the next morning warmed and smeared over the skin. Yellow, by smearing the skin over with aloes and linseed oil dissolved and strained; or by infusing it in weld. Orange colour is given by smearing with fus- tic berries boiled in alum water; or, for a deep orange, with turmeric.
Processes for Dyeing Leather Red and Yellow as practised in Turkey, with directions for Preparing and Tanning the Skins; as communicated by Mr. Philippo, a native of Armenia, who received from the Society for the Encouragement of Arts, &c. one hundred pounds, and also the gold medal of the Society, as a reward for discovering this secret.
1. First Preparation of the Skins, both for Red and Yellow Leather, by dressing them in Lime. Let the skins, dried with the hair on, be first laid to soak in clean water for three days; let them then be broken over the flesh side, put into fresh water for two days longer, and afterwards hung up to drain half an hour. Let them now be broken on the flesh side, limed in cold lime on the same side, and doubled together with the grain side outward. In this state they must be hung up within doors over a frame for five or six days, till the hair be loose; which must then be taken off, and the skins returned into the lime pit for about three weeks. Take them out, and let them be well worked flesh and grain, every sixth or seventh day dur- ing that time; after which, let them be washed ten times in clear water, changing the water at each wash- ing. They are next to be prepared in drench, as be- low mentioned.
Vol. XI. Part II.
2. Second Preparation of the Skins for both the Red Leather, and Yellow Dyes by drenching. After squeezing the water out of the skins, put them into a mixture of bran and water, warm as new milk, in the following pro- portions; viz. about three pounds of bran for five skins, and water sufficient to make the mixture moder- ately fluid, which will be about a gallon to each pound of bran. In this drench let the skins lie three days; at the end of which time they must be well worked, and afterwards returned into the drench two days longer. They must then be taken out and rub- bed between the hands; the water squeezed from them, and the bran scraped off clear from both sides of the skins. After this they must be again washed ten times in clear water, and the water squeezed out of them.
Thus far the preparatory process of all the skins, whether intended to be dyed red or yellow, is the same; but afterwards those which are to be dyed red, must be treated as follows.
3. Preparation in Honey and Bran of Skins that are to be dyed Red. Mix one pound of honey with three pints of lukewarm water, and stir them together till the honey is dissolved. Then add two double handfuls of bran; and taking four skins (for which the above quantity of the mixture will be sufficient), work them well in it one after another. Afterwards fold up each skin separately into a round form, with the flesh side inwards; and lay them in an earthen pan, or other proper vessel; if in the summer, by the side of each other; but in the winter, on the top of each other. Place the vessel in a sloping position, so that such part of the fluid as may spontaneously drain from the skins, may pass from them. An acid fermentation will then rise in the liquor, and the skins will swell considerably. In this state they must continue for seven or eight days; but the moisture that drains from them must be poured off, once or twice a-day, as occasion may re- quire. After this a further preparation in salt is ne- cessary; and which must be performed in the following manner.
4. Preparation in Salt, of the Skins to be dyed Red. After the skins have been fermented in the honey and bran, as above mentioned, let them be taken out of that mixture on the eighth or ninth day, and well rubbed with dry common sea salt, in the proportion of about half a pound to each skin; the salt must be well rub- bed and worked with them. This will make them con- tract again, and part with a further considerable quan- tity of moisture; which must be squeezed out by draw- ing each skin separately through the hands. They must next be scraped clean on both sides from the bran, superfluous salt, and moisture that may adhere to them. After which, dry salt must be strewed over the grain- side, and well rubbed in with the hand. They are then to be doubled with the flesh side outwards, length- wise from neck to tail, and a little more dry salt must be thinly strewed over the flesh side, and rubbed in; for the two last operations, about a pound and a half of salt will be sufficient for each skin. They must then be put, thus folded on each other, between two clean boards, placed sloping, breadthwise; and a heavy weight laid on the upper board, in order gradually to press out what moisture they will thus part with. In this state of pressure, they must be continued two days. 5. Preparation of the Red Dye, in a proper proportion for four Skins. Put eight gallons of water into a copper, with seven ounces of shenan (A) tied up in a linen bag. Light a fire under a copper; and when the water has boiled about a quarter of an hour, take out the bag of shenan, and put into the boiling fluid or lixivium, 1st, Two drams of alum; 2dly, Two drams pomegranate bark; 3dly, Three quarters of an ounce of turmeric; 4thly, Three ounces of cochineal; 5thly, Two ounces of loaf sugar. Let the whole mixture boil about six minutes, then cover the fire, and take out a quart of liquor, putting it into a flat earthen pan; and when it is as cold as new milk, take one skin, folded lengthwise, the grain side outwards, and dip it in the liquor, rubbing it gently with the hands. Then taking out the skin, hang it up to drain, and throw away the superfluous dye. Proceed in the same manner with the remaining three skins; repeating the operation of each skin separately, eight times, squeezing the skins by drawing them through the hands before each fresh dipping. Lay them now on one side of a large pan, set sloping, to drain off as much of the moisture as will run from them without pressure, for about two hours, or till they are cold; then tan them as below directed.
6. Tanning the Red Skins. Powder four ounces of the best white galls in a marble mortar, sifting it through a fine sieve. Mix the powder with about three quarts of water, and work the skins well in this mixture for half an hour or more, folding up the skins four-fold. Let them lie in this tan for 24 hours; when they must be worked again as before; then taken out, scraped clean on both sides from the first galls, and put into a like quantity of fresh galls and water. In this fresh mixture they must be again well worked for three quarters of an hour; then folded up as before, and left in the fresh tan for three days. On the fourth day they must be taken out, washed clean from the galls in seven or eight fresh quantities of water, and then hung up to dry.
7. Manner of Dressing the Skins after they are tanned. When the skins have been treated as above, and are very near dry, they should be scraped with the proper instrument or scraper on the flesh side, to reduce them to a proper degree of thickness. They are then to be laid on a smooth board, and glazed by rubbing them with a smooth glass. After which they must be oiled, by rubbing them with olive oil, by means of a linen rag, in the proportion of one ounce and a half of oil for four skins: they are then to be grained on a graining board, lengthwise, breadthwise, and cornerwise, or from corner to corner.
8. Preparations with Galls, for the Skins to be dyed Yellow. After the four skins are taken out of the drench of bean, and clean washed as before directed in the second article, they must be very well worked, half an hour or more, in a mixture of a pound and a half of the best white galls, finely powdered, with two quarts of clean water. The skins are then to be separately doubled lengthwise, rolled up with the flesh side outwards, laid in the mixture, and close pressed down on each other, in which state they must continue two whole days. On the third day let them be again worked in the tan; and afterwards scraped clean from the galls, with an ivory or brass instrument (for no iron must touch them). They must then be put into a fresh tan, made of two pounds of galls finely powdered, with about three quarts of water, and well worked therein 15 times. After this they must be doubled, rolled up as before, and laid in the second tan for three days. On the third day a quarter of a pound of white salt must be worked into each skin; and the skins doubled up as before, and returned into the tan, till the day following, when they are to be taken out, and well washed six times in cold water, and four times in water lukewarm. The water must be then well squeezed out, by laying the skins under pressure, for about half an hour, between two boards, with a weight of about 200 or 300 pounds laid upon the uppermost board, when they will be ready for the dye.
9. Preparation of the Yellow Dye, in the proper proportion for four Skins. Mix six ounces of cassiari gehira (B), or dgehira, or the berries of the eastern rhamnus, with the same quantity of alum; and pound them together till they be fine, in a marble or brass mortar, with a brass pestle. Then dividing the materials, thus powdered, into three equal parts of four ounces each, put one of those three parts into about a pint and a half of water, in a china or earthen vessel, and stir the mixture together. Let the fluid stand to cool, till it will not scald the hand. Then spreading one of the skins flat on a table, in a warm room, with the grain-side uppermost, pour a fourth part of the tinging liquor, prepared as above directed, over the upper or grain-side, spreading it equally over the skin with the hand, and rubbing it well in. Afterwards do the like with the other three skins, for which the mixture first made will be sufficient.
This operation must be repeated twice more on each skin.
(A) Shenan is a drug much used by dyers in the east; and may easily be procured at any of the ports of Syria and Africa, in the Levant. It is the eastern jointed-kali, called by botanists salicornia; and grows in great plenty in those and other parts of the east. There is a lesser species of the salicornia on our coast, which, from its great affinity with the shenan, might be presumed to have the same qualities. On some trials, however, it has not appeared to answer the intention of the shenan; but it will be prudent to pursue the examination of this further, as some unknown circumstances in the collecting or using the English salicornia might occasion the miscarriage. But be this as it may, the eastern shenan may, at all events, be easily procured in any quantity, at a very trifling expense, by any of the captains of Turkey ships, at Aleppo, Smyrna, &c.
(B) The cassiari gehira is the berries of an eastern rhamnus, or buckthorn tree; and may be had at Aleppo, and other parts of the Levant, at a small price. The common Avignon or yellow berries may be substituted, but not with so good an effect; the cassiari gehira being a stronger and brighter yellow dye, both for this use and also that of colouring paper hangings, &c. skin separately, with the remaining eight ounces of the powder of the berries, and alum, with the above-mentioned due proportions of hot water, put to them as before directed.
The skins, when dyed, are to be hung up on a wooden frame, without being folded, with the grain-side outwards, about three quarters of an hour to drain; when they must be carried to a river or stream of running water, and well washed therein six times or more. After this they must be put under pressure for about an hour, till the water be well squeezed out; afterwards the skins must be hung up to dry in a warm room.
This being done, the skins are to be dressed and grained as before directed for those dyed red; except the oiling, which must be omitted.
Blackening Leather. In the tanning of leather it is so much impregnated with the astringent parts of oak bark, or with that matter which strikes a black with green vitriol, that rubbing it over three or four times with a solution of the vitriol, or with a solution of iron made in vegetable acids, is sufficient for staining it black. Of this we may be convinced by dropping a little of the solution on the unblackened side of common shoe leather. This operation is performed by the currier; who, after the colouring, gives a gloss to the leather with a solution of gum arabic and size made in vinegar. Where the previous astringent impregnation is insufficient to give due colour, and for those sorts of leather which have not been tanned, some galls or other astringents are added to the solution of iron; and in many cases, particularly for the finer sorts of leather, and for renewing the blackness, ivory or lamp-black is used. A mixture of either of these with linseed oil makes the common oil blacking. For a shining blacking, small beer or water is taken instead of oil, in the quantity of about a pint to an ounce of the ivory black, with an addition of half an ounce of brown sugar and as much gum arabic. The white of an egg, substituted for the gum, makes the black more shining, but is supposed to hurt the leather, and make it apt to crack. It must be obvious, however, that all these compositions admit of a great many variations.
Gilding of Leather. Take glair of the whites of eggs, or gum water, and with a brush rub over the leather with either of them: then lay on the gold or silver, and, letting them dry, burnish them. See the articles Gilding and Burnishing.
To dress or cover Leather with Silver or Gold. Take brown-red; grind or move it on a stone with a muller, adding water and chalk; and when the latter is dissolved, rub or lightly daub the leather over with it, till it looks a little whitish; and then lay on the leaf-silver or gold before the leather is quite dry, laying the leaves a little over each other, that there may not be the least part uncovered; and when they have well closed with the leather, and are sufficiently dried on and hardened, rub them over with an ivory polisher, or the foretooth of a horse.
By several statutes, regulations are made for the tanning and manufacturing of leather; and by the 27th Geo. III. c. 13., a duty is laid upon all hides and skins imported, and drawbacks allowed on the exportation thereof. Several duties are also imposed on hides and skins tanned in Great Britain, of what kind soever, as set forth in schedules annexed to the said act. By the 23 Geo. III. c. 37., further regulations are made respecting the said duties, which are under the management of the officers of excise.