Dr. Bolley on the Theory of Dyeing. 49S 



Table {continued). 

 Series E. Solution of Acetate of Lead. 10 cubic centims. = 0-28338 oxide. 



Name and weight 



in grammes 



of substance digested. 



•2^ 



Analysis of solution after digestion. 



28 



29 



1750 Wool 



5-951 Raw silk... 



30 5-4750 Scoured silk 



31 4-883 Cotton 



47-5 



59-5 

 54-7 



48-8 



10 = 0-2588 oxide, required 1-2 c.c. ^ Standard potash solu- 

 tion for the commence- 

 ment of precipitation*. 



10 = 0-2387 

 10 = 0-2580 

 10 = 0-28338 



1-5 



1-2 

 0-4 



Series F a. Solution of Alum. 10 cubic centims. = 00758 AFO^ and 02289 SO^, that is 

 100 A12 03; 301-99 SOSf. 



4-5210 Wool 90-4 



4-44 Wool 44-4 



3-9710 Cotton 397 



4-7105 Raw silk ... 470 



10 = 00685 AFQS and 0■2193SO■^thatisl00A13O3 

 10 = 00661 „ 0-2284 



10 = 0-0705 „ 0-2192 „ „ 



10=0-0651 „ 0-2323 „ „ 



320 29SO3 

 345-84 „ 

 310-92 „ 

 356-99 „ 



Series F b. Sohition of Alum, 40 cubic centims. = 0-3985 AP 0^ and 1-2618 SO^, that is 

 100 A12 03: 316-38 SOsf. 



36 7-2785 Wool 



37 6-9350 Wool 



40 = 0-3655 AP03 and 1-225 SO^.thatislOOAPO^ : 335-16SOS 

 40 = 0-3690 ,, 1-224 „ „ : 331-70,, 



Series G. Experiments made with a solution of persulphate of iron, as nearly as possible 

 neutral, proved that all three sorts of fibres took a permanent yellow dye, which was 

 considered as a clear proof that they had taken up a basic salt. 



The conclusions that may be drawn from this summary are as 

 follows : — 



From series A we learn : — That wool, silk, and charcoal weaken 

 a solution of sulphuric acid by abstracting part of the acid, 

 though to no great extent ; that cotton, on the other hand, is 

 without effect. (Chevreul found that cotton, by abstracting water 

 from the solution, left the acid somewhat stronger.) 



In the fresh solution, by evaporatin<^, ignition, extracting with water, and 

 again eviiporating and heating, a residue was found which answered to 

 439 KO. 



* Served to show whether free acetic acid or au acid salt of lead were 

 pre.sent. 



t In ammonia-alum, according to the formula, there arc .31<)-()5 SO^ to 

 100 AFO''; the slight deficiency of suli)huric acid was the reason for re- 

 peating the cxperimcnt.s with another solution. 

 2 K2 



