so 



CHEMICAL RESEARCHES ON THE ANIMAL FLUIDS. 



the metallic oxide combined with the colouring matter, and a 

 small portion of coagulated albumen. Tiie remaining fluid 

 had nearly lost its red colour, 

 of the black. The nitrate of mercury containing the black oxide produces 

 nearly similar effects, excepting that the colour of the com- 

 pound is of a lighter red. 

 Corrosive sub- When corrosive sublimate is added to the solution of the 

 Iimate. colouring matter, its tint is instantaneously brightened, and it 



becomes slightly turbid from the deposition of albumen. If 

 this be immediately separated by a filter, the liqijor which 

 passes through gradually deposits a deep red or purplish insolu- 

 ble precipitate, and if it now be again filtrated the liquid is co- 

 lourless, the whole of the colouring principle being retained in 

 the compound which remains upon the filter. 

 These salts By impregnating some pieces of woollen cloth with solution 



lised as rtor- ^f nitrate of mercury, or of corrosive sublimate, and after- 

 ward steeping them in an aqueous solution of the colouring 

 matter of the blood, I succeeded in giving them a permanent 

 red tinge, unalterable by washing with soap ; and by employing 

 the ammoniacal solution of the colouring matter, calico and 

 linen may be dyed with the same mordant. 



In these experiments I was much satisfied by the complete 

 separation of ihe colouring matter from its solutions, which 

 after the process were perfectly colourless. 



VII. Some Remarks on the preceding experimental Details. 



Analogy be- From the experiments related in the second section of this 



ImiTof cMe" P'^^P^^J '^ appears, that sulphuric acid effects changes upon the 



andcuid of coagulum of chyle, similar to those which Mr. Hatchett has 



""^^- observed to result from the action of dilute nitric acid upon 



the coagulated white of egg. This last substance, however, 



is not convertible into gelatine by means of sulphuric acid, 



whereas in these respects the curd of milk resembles that of 



chyle: this circumstance, as well as the more ready solubility 



of the coagulum of chyle in dilute, than in concentrated acids, 



points out a strong analogy between these two bodies. 



?>weet taste of The sweet taste of chyle naturally suggested the idea of its 



chyle. containing sugar* 3 but I am not aware of any direct experi- 



• Fordyce en Digestion, 2d Edition, p. 121. 



ments 



