TANNIXG. 14T 



rative experiments with oak-bark, alfler-bark, eatechn, di- 

 vidivi, that sole-leather tanned with dividivi is, in dry weather, 

 about as good as the oak-tanned, but that in wet weather it is 

 inferior. It may, nevertheless, be used in conjunction with 

 oak-bark. (Verb. d. Gewerbfl. f. Preussen, 1847.) 



Eisner states that in Wallachia, Moldavia, and Transylvania, 

 the root of the tormentil or septfoil is largely and success- 

 fully employed in tanning, and that its value is shown by 

 chemical analysis, which gives 17 to 34 per cent, tannin in it. 



The best method of determining, practically, the amount of 

 tannin in a substance is that proposed by Pelouze, which is to 

 hang a strip of hide (freshly deprived of hair and ready for 

 the tan-vat) in a tannic solution, and keep it there until it 

 ceases to increase in weight. This increase is tannic acid, the 

 gallic being left in the solution. 



Horse-Jiair, Dyed. — Previous to dyeing, it is cleaned by 

 laying it for 24 hours in soapsuds heated to 130°, turning it 

 repeatedly. For brown, it is laid for 12 hours in a decoction of 

 logwood in lime-water cooled down to 120°, washed and dried. 

 If the brown hair be dipped into water containing a little 

 crystallized tin-salt, it assumes a violet-blue shade. To give 

 a blue color, the hair is first mordanted in a hot solution of 

 2 pts. alum and 1 pt. argal, wrung out, then passed through 

 water containing a little sulphate of indigo, washed, and dried. 

 For red, it is laid for a \ hour in water containing tin-salt, 

 wrung out, laid for 24 hours in a bath prepared by boiling 

 redwood with alum, washed, and dried at a gentle heat. (De- 

 ningerin Monatsbl. d. Gewerbver. f. d. Grossh. Hessen, 1847.) 



Sair Varnish. — Williams (Monit. Indust. 1848) gives the 

 following recipe for a varnish for converting fibrous materials 

 into " artificial hair." It is made by dissolving 10-40 pts. 

 hog bristles in 100 pts. linseed-oil varnish. The cloth is to 

 be immersed in the liquid and then dried at a moderate 

 temperature. 



Ilorn^ Dyed. — To give it the appearance of tortoise-shell, 

 a paste of 2 pts. lime, 1 pt. litharge, and a little soda-lye is 

 Crushed on, and, after drying, brushed off again. It is the 



