GENERAL COMPOSITION. 153 



and are even capable of abstracting the oxygen which is combined with 

 haemoglobin, so that arterial blood rapidly becomes converted into venous 

 blood, when it is not exposed to the access of fresh oxygen. It is not known 

 upon what substance or substances these properties depend, but it is prob- 

 able that it is a function of the protoplasm of cells, and, in the case of the 

 blood, it may be due to the protoplasm of the white corpuscles. 



General composition. The general composition of blood and the 

 relative distribution of its constituents in the corpuscles and plasma 

 respectively is illustrated in the accompanying tables from C. Schmidt l 

 and Bunge. 2 



Venous Blood of a Man, cet. 25, sp. gr. 1*0599 (C. Schmidt). 

 In 1000 grms. blood corpuscles (sp. gr. 1*0886) 



Water . . . . . .. 681*63 



Substances not vaporising at 120 C. 318'37 



Haemoglobin and other proteid substances . . 311*09 



Inorganic substances 



Chlorine .... 1*750 



Sulphuric acid . . . .0*061 



Phosphoric acid . . . . 1*355 



Potassium . . . .3*091 



Sodium .... 0*470 



Phosph. lime .... 0*094 



Phosphate magnesia . . . 0*060 



Oxygen. .... 0*401 



Total of inorganic constituents (exclusive of iron) 7*282 



In 1000 grms. plasma (sp. gr. 1*0312) 



Water . . . . . . .901*51 



Substances not vaporising at 120 C. 98*49 



Fibrin . . . . . . 8*06 



Other proteids and organic substances . . , 81*92 

 Inorganic substances 



Chlorine . . . 3*536 

 Sulphuric acid . . . .0*129 



Phosphoric acid .... 0*145 



Potassium . . . . 0*314 



Sodium ..... 3*410 



Phosphate lime .... 0*298 



Phosphate magnesia . . . 0.218 



Oxygen . . . . . ' 0*455 



Total of inorganic constituents 8*505 



In this estimation the phosphoric acid is probably too high, being 

 increased in the process of calcining by the phosphorus in the lecithin. 

 Sertoli, 3 by eliminating this error, obtained only 0'025 grin, phosphoric 

 acid per 1000 grms. ox serum, equivalent to only 0'005 per cent, hydro- 

 disodic phosphate (Na 2 HP0 4 ). 



It is clear from the following table that there are considerable 

 differences in the composition of the whole blood and of its parts in 



1 "Charakter. der epid. Cholera," Leipzig, 1850. 



2 Ztschr. f. BioL, Miinchcn, 1876, Bd. xii. S. 191; and "Physiol. and Pathol. 

 Chemistry," trans, by Wooldridge, 1890, p. 245. 



3 Sertoli in Hoppe-Seylers Med. Chem. Untersuch.. Berlin, 1868, S. 352. See also 

 Miroczkowski, Centralbl. f. d. med. Wissensch., Berlin, 1878, S. 353, who obtained in calf 

 serum, O'OIS ; in sheep serum, 0.0092 and 0'0064 ; and in dog serum, 0*0083 parts 

 Na a HP0 4 per 100 serum. 



