32 Dr. G. O. Rees on a Function of the 



few hours in such a manner as to decolorize the fluid above, a 

 precipitate falling composed of the haematosine combined with 

 oxide of zinc. This precipitate was collected and digested 

 with aether. On evaporating the sethereal solution, fatty mat- 

 ter was obtained in considerable quantity. 



Exp. 8. Venous blood was drawn from the external jugular 

 of a large poodle, and subsequently arterial blood from the 

 carotid of the same animal. The serum was full of chyle in 

 both specimens. 



The presence of an alkaline carbonate in the ashes of the 

 serum was ascertained in both cases, but in larger quantity 

 in the venous than arterial serum. The reverse was the case 

 with regard to the alkaline phosphate, which, though present, 

 existed in smaller proportion in the venous than the arterial 

 serum. 



The fats of the arterial crassamentum yielded an alkaline 

 ash. That obtained from the venous crassamentum gave an 

 acid reaction. 



In the experiments on serum which 1 have described above, 

 I have generally used a very small quantity of the fluid. My 

 principal object having been to show the difference in propor- 

 tion of alkaline phosphate existing between venous and arte- 

 rialized blood, I always took care to use a larger quantity of 

 the former than of the latter in these comparative experiments, 

 in order that my theory, which presumed an excess in arterial 

 serum, might be the more severely tested, and that the alka- 

 line phosphate might be prominently shown in the venous 

 serum if it had happened to be present, even in proportion 

 approaching that in which it existed in arterial serum. When 

 larger quantities of venous serum are operated upon, an alka- 

 line phosphate ma)' be detected. I however obtained no evi- 

 dence from the quantity I used, viz. from twenty-five to forty 

 grains. 



The results now stated appear sufficiently to prove the cor- 

 rectness of the theory I have advanced. Thus, not only does 

 arterial serum prove to contain more alkaline phosphate than 

 that from the venous blood, but we are able, by artificially 

 arterializing a portion of blood, to remove the phosphorus of 

 the corpuscles into the liquor sanguinis by forming phosphoric 

 acid, which is absorbed by the alkali contained in the fluid. 



The fatty matter from the corpuscles of venous blood proves 

 to contain phosphorus, yielding an acid ash on incineration. 

 Vide Exp. 3. The fatty matter from the corpuscles of arterial 

 blood yields an alkaline ash on incineration. Vide Exp. 4. The 

 fatty matter of the corpuscles exists in close combination with 

 the colouring matter, and in all probability is its most essential 



