330 Phcenojjiena afforded by Animal JMathrs 



M-hich also remains in solution; 4. of the formation of tlie 

 malic acid. 



It appears, and it is the opinion of Messrs. Fourcroy and 

 Vauquelin, that the yellow and little soluble matlcr is the 

 first degree of change which the muscular fibre undergoes ; 

 It passes immediately into a second sta^e of alteration and 

 acidity, and the yellow soluble matter is produced : this, 

 by a third change, is replaced by the inflammable and deto- 

 nating substance forming the third and last step in the 

 decomposing action of the nitric acid. Thev attribute the 

 ^successive formation of these three compounds to the sub- 

 traction of a portion of the azote, and of a larger quantity 

 of the hydrogen of the muscular flesh : in this way the re- 

 lative proportions of their elements are altered, and there 

 remains an excess of carbon and oxvgen, which connnuni- 

 cates those characters of fat and acidity which we remark. 

 The proportion of the principles constituting these three 

 compounds is a question of such difficulty that we cannot 

 c.vpict it will soon be resolved. 



They are convinced that tlie aciditv of the yellow sub- 

 stances depends in no degree upon the presence of nitric 

 acid, as thev have failed in every attempt to detect it. 



The oxalic and malic acids, th^y conceive, are formed 

 from the white and mucous layers of cellular substance ; 

 and the opinion is confirmed by comparative experiments 

 on the while and membranous parts of the body, which 

 show that these yield, on the application of the nitric acid, 

 a large quantity of the malic and oxalic, but very little fat 

 or yellow matter. 



VL Some insulated facts, which have hitherto appeared 

 susceptiiilc of no useful application, seem naturally to con- 

 nect themselves with those presented by the analysis before 

 us ; and the learned chemists to whom we owe it have very 

 happily pointed out the connection. Such are the facts 

 which were offered by the examination of the biliary con- 

 cretions of some animals, more especially those found in 

 the gall bladder of the ox : such also are the resemblances 

 which serve to show the connection between the bile and the 

 colour of the skin and urine in cases of kicms (janndice), 

 and the yellow substances which are mentioned in this me- 

 moir. 



Further experiments, instituted with a view to verify their 

 suspicions, were attended with the most favourable results. 

 The red matter of biliary concretions, when separated by 

 alcohol from the green bitter matter with which it is mixed, 

 presented the same characters which distinguished the first 



yellow 



