2*> On the Heat evolved darrvg \ivvt 9 



7. In solution of caustic fixed alkali the colouring matter b 

 softened, forming a brownish jelly, which is dissolved by a suffi- 

 cient quantity of water. During tire evaporation k coagulates in 

 proportion as the alkali absorbs carbonic acid. The alkaline 

 solution is precipitated by alcohol, which, however, acquires a 

 red tinge by dissolving a small quantity of the compound formed 

 ©f the colouring matter with the excess of alkali. The alkaline 

 solution of colouring matter seen by day-light has a green colour, 

 but appears red by candle-light. It was upon this appearance of 

 green that Fourcroy conceived the idea that bile might be formed 

 fey boiling blood with a small quantity of water; but this green 

 fluid, as we shall afterwards see, agrees with bile in no property 

 excepting colour. 



8. If a solution of the colouring matter in water be exposed 

 to a heat of 50° (122° Fahrenheit) in a saucer, it blackens and 

 dries completely without coagulating. In this state it is again 

 entirely soluble in cold water. 



These experiments prove that the colouring matter has the same 

 chemical properties, and consequently the same chemical com- 

 position as fibrin, but that these two bodies are distinguishable 

 from one another principally by a difference in colour; by the 

 fibrin coagulating spontaneously in all temperatures, while the 

 colouring matter may be dried, without losing its solubility in 

 water, and becomes insoluble only at a certain temperature: and 

 lastly by the peculiar character of the latter when coagulated, 

 5uch as its not being diminished in volume during the exsicca- 

 tion, as happens with fibrin. 



(To be continued.) 



Article VII. 



On the Heat evolved during Inflammation of the Human Body. 

 By Thomas Thomson, M.D. F.R.S. 



That the heat evolved by the human body is very consider-* 

 able, and that in cases of inflammation this heat is very much 

 increased, are facts with which every body is acquainted; but I 

 am ignorant of any attempt hitherto made to estimate the 

 increase of beat that is given off in cases of inflammation. On 

 that account 1 think it worth while to record an observation 

 which I had an opportunity of making upon myself, during the 

 course of last winter. It is far from determining the whole heat 

 given off during the inflammation ; but as it is at least an 

 approach towards accuracy, and as I was at as much pains as 



