and some of its Products of Decomposition. 61 



Basic Sulphate of Glycocoll. 



(c.) 3(G1, HO)2S0 3 , HO. 

 A mixture of the salt (b) with the previously described one 

 (a), doubtless gave the crystals for the following determination : 



1 1-3076 grm. gave 0-2300 grm. sulphate of baryta, which gives in 



per cent, expressed, sulphuric acid 25-65 : corresponding with the 

 above formula. The following is more rational. 



(Gl, SO,, HO+Gl, HO)+(Gl, H0 + S0 7 HO). 

 This requires 25-47 parts of sulphuric acid in 100. 



(d.) 2(GI.HO) + SO n . 

 Another salt gave by combustion with chromate of lead, 

 From 0-3039 grm., 0-2872 grm. carbonic acid, and 0-1680 

 grm. water; which expressed in per cent., give carbon 2577, 

 hydrogen 6-01. These numbers correspond with the formula 



2(C\ II , NO : „HO) + SO„ 



winch requires carbon 25-26, and hydrogen 5-26. 



Glycocoll and Sulphate of Oxyd of Ethyl. 



Gl, HO, AeO, S0 3 . 



The particular circumstances of the formation of this salt, be- 

 yond those already given, viz. a solution in hot spirits of wine, or 

 in water to which absolute alcohol was added, are not ascertained. 



A\ ith chlorid of barium, 0-6470 grm. gave 0-3036 grm. sul- 

 phate of baryta; which in per cent, give of sulphuric acid 17-27. 

 1 his quantity of acid corresponds with the formula 



0,H 4 N0„HO+C 4 H 8 O,SO 8 , 



wnicn requires 17-62 per cent, of sulphuric acid. 



Nitrate of Glycocoll. 



Gl, HO 4- NO,, HO. 



The capability which this compound possesses of uniting with 

 bases enveloped the earlier conceptions of the nature of glyco- 

 C °U in obscurity: — an obscurity from which the changes the 

 nitrate of copper salt experienced upon subjection to heat, and 

 Joe simple combinations with the oxyds of silver, copper and 

 ,e ad, did not in any degree relieve it. It was then sugg< ted 

 that the glycocoll played the part of the water of crystallization 

 jB the salts that were formed. From the analysis below, it will 

 be seen that the salts were double salts, in which glycocoll with 

 °r without water, as a base, united with hydrated nitric acid, or 

 ^ a salt with nitrates of metallic oxyds. 

 . Braconnot obtained this compound by direct combination of 

 toe acid with glycocoll prepared from isinglass. Dessaigne 

 procured it directly from hippuric acid, employing nitric instead 

 01 hydrochloric acid for its decomposition. 



