HJEMATIN. 301 



colours, is unaffected by acids and alkalies, but which, when warmed 

 with hydrosulphate of ammonia, assumes a red colour. 



On passing dry hydrochloric acid gas over dry hsematin, 

 there is formed a violet mass, which is soluble both in water and 

 alcohol, communicating to those fluids a red colour and an acid 

 reaction. 



If hsematin be allowed to remain for some time in contact with 

 pure concentrated sulphuric acid, and the fluid be then diluted with 

 water, there is a development of hydrogen gas, and sulphate of 

 protoxide of iron is taken up in solution. By a repetition of this 

 process the whole of the iron, with the exception of a mere trace, 

 may be removed from the hsematin, without depriving it of its 

 properties and without altering its elementary composition, as far 

 as the relative amounts of the carbon, hydrogen, nitrogen, and 

 oxygen are concerned. 



We are indebted to Mulder and van Goudoever* for the pre- 

 paration of hsematin free from or poor in iron; Sanson and 

 Schererf had, however, previously observed that concentrated 

 sulphuric acid could extract all the iron from the clot or the 

 residue of the blood- corpuscles, without affecting its dark brown 

 colour. 



Composition. MulderJ has calculated, from his analyses, the 

 formula we have given for haematin, according to which it contains : 



Carbon 44 atoms .... 65'347 



Hydrogen 22 .... 5*445 



Nitrogen 3 .... 10'396 



Oxygen 6 .... 11-881 



Iron 1 .... 6-931 



100-000 



Mulder's analyses of hsematin free from iron coincide with the 

 formula C 44 H 22 N 3 O 6 . From the chloride of hsematin Mulder cal- 

 culates that the atomic weight of hsematin is 5175. 



Chloride of hce matin, formed from dry chlorine gas and hsematin, 

 consists of 1 equivalent of hsematin, and 6 equivalents of chlorine ; 

 how this combination may be supposed to be formed, is a point on 

 which at present we can offer no conjecture. The compound 

 obtained from dry hydrochloric acid gas and hsematin consists, 

 according to Mulder, of 2 equivalents of hsematin and 3 equivalents 

 of hydrochloric acid; on exposing this substance to a heat of 100, 



* Journ. f. pr. Ch. Bd. 325, S. 186, ff. 

 t Ann d. Ch. u. Pharm. Bd. 40, S. 30. 

 J Journ. f. pr. Ch. Bd. 28, S. 340. 



