DYE

DYE

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foda This finifhing brings out the colour, andpinch increafes its riehnefs and durability.

Such is, according to the belt authorities,the curious and complicated procefs for dyeingthe beautiful Adrianople red. On the whole itappears that the faving which may be made inimitating this procefs is rather in the numberand extent of the different operations, than inthe adtual omiffion of any one part. The ani-mal matter, the oil, the foda, the galls, and thealum, appear all to have their diftindl ufes, andprobably it would be very difficult to difpenfewith any of them (or fubftances limilar to them)without injuring the perfection of the dye.

The fine imitation of this colour made atMontpellier is conduced in a manner clofelyfollowing the Turkey procefs according to theteftimony and afitual experience of Chaptal.

The obfervations of this excellent practicalchemift give many important rules with regardto the choice and ufe of the materials too mi-jiute to be fully detailed in this place. Infteadof fheep’s dung the gaftric liquor contained inthe ftomach of ruminating animals is employed,in each cafe, mixed with the oil and foda intoa kind of oleo-animal foap. The oil fliould beof that kind which remains permanently unitedwith cauftic alkali into a uniform milky foap,without fubfiding or running again into dropsin any fenfible degree. This kind of oil is pro-bably that which is the freed from extractivematter, and the obfervations of other chemiftshave found that linfeed oil which contains verylittle extract is even better than any kind ofolive oil.

It alfo feems neceffary that in the mixture ofoil and alkali the oil ffiould be in excefs, or ingreater quantity than in the proportions whicheonftitute common foap : for the ufe of thealkali is chiefly to divide the oil and enable itto penetrate uniformly into the cotton, but ifthere were no excefs of oil it is not likely thatthe alkali would abandon any of it to the fibresof the cotton. Soda does not appear to be ef-fential, potaffi being found to anfwer as well.

The galling is one of the niceft operations.The cotton ffiould be made to take the gallsvery uniformly, and fliould be dried rapidly, asthe action of the air is found fo far to affedbthe foluble matter of the galls that, if much ex-pofed to it, the outer part of the cotton will be-come dark, and the remainder grey, and thefubfequent colour will in confequence take un-equally. Sumach is ufed with the galls inrather a larger proportion. The repetition of

the oiling, galling, and aluming is pra&ifed atMontpellier as in Turkey. In the finifhing parttwo operations are ufed. The firft is, as inTurkey, boiling with foda. and foap in a veryhigh temperature. The boiler is clofely fittedwith a ftrong cover with only a very fmall holefor the exit of the vapour, and by the heat ofthe fire beneath the confined liquor is made toreceive a heat certainly above that of commonboiling, fimilar to what takes place in a digefter.This brings out the colour to a very beautifulred, but it is further heightened by the finaloperation which was long kept fecret, andwhich confifts in palling the cotton through amixed folution of nitro-muriat of tin and alum,at a blood heat.

Linen thread is dyed of a fine red by thefame method, but a ftill greater number offucceffive operations are required, and in par-ticular the alkaline leys ffiould be muchftronger.

Madder reds of extreme beauty are preparedby the Armenian dyers fettled at Aftracan.The procefs as given by Profefl'or Pallas™ ismore Ample than that practifed at Adria-nople , but agrees with it in the effential par-ticulars. The madder is a fine fort that growswild in feveral parts of Perfia, and is dried andground for ufe. The oil employed is procuredfrom the entrails and refufe parts of the ftur-geon, beluga, and other fiflr that are fo abun-dant in the Volga. This fupplies both oilyand animal matter. The alkali employed is acoarfe native foda, prepared by burning variousfait plants in the vicinity. But the oil feems tobe ufed without alkali, the foda being only em-ployed in the finifhing. The general procefsis as follows: the cotton yarn previoufly walhedand well dried is laid in a tub, and coveredwith the fiffi oil, where it remains for the night.In the morning it is taken out and hung up inthe air on poles. This alternate fteeping in oilduring the night and airing during the day iscontinued for a week, after which the yarn iswaffied in the river and dried. A ftrong de-coction is then made of pulverized fumachleaves and galls, to which, when ftill hot, alumis added. The galls and alum are in the pro-portion of 5 pound of each to every pud (40 lb.)of cotton. This compound liquor is pouredon the cotton, and well worked in with thehands, and the yarn again dried. It is then fitfor the maddering, in which ffieeps blood ishere alfo ufed along with the madder. Thewhole operation is.finilhed by boiling the dyed

Tooke’s Ruffian Empire vol, iii. p.4?7-