Chemical Composition of Human Blood, 117 



the following conclusions respecting the proportion of the 

 constituents of the hlood : 



The water varies ; it is less in man than in woman. The 

 quantity is not proportional to the age, beyond the limits 

 of twenty to sixty years. In individuals of the same sex, 

 it is less in those of a sanguine temperament, than in those 

 of a lymphatic. 



The albumen is sensibly the same in both sexes, and is 

 proportional to the age, within the limits of twenty to sixty 

 years. The temperament does not appear to affect the 

 quantity. 



The proportion of globules is greater in man than in 

 woman ; it is greatest also in those of the sanguine tempe- 

 rament. 



The serum is greater in proportion in woman than in man, 

 and also in the lymphatic than in the sanguine tempera- 

 ment.* 



From the experiments of Mr. Andrews, the quantity of 

 globules and albumen seems also to decrease from repeated 

 bleedings .f 



I. THE CLOT. 



The clot is of a red colour and soft, and possesses a spe- 

 cific gravity of 1*126, as determined by Haller. To sepa- 

 rate it from the serum, I followed the plan proposed by 

 Dumas and Prevost. 



The weight of the whole blood is taken, and the serum 

 separated as well as possible by a sucker. The serum is 

 then weighed, which, subtracted from the weight of the 

 blood, gives the weight of the clot. Weighed portions of 

 the serum and clot are then carefully evaporated to dryness, 

 and what remains is weighed. The water in the clot, being 

 in the state of serum, its quantity is easily determined from 

 the above data. 



After these preliminary experiments, the remaining clot 

 is cut into small pieces and heated with water, till all saline 

 matter is washed away. 



This pure clot is mingled with water, and the whole often 

 agitated. The water dissolves the hematosine, or colouring 

 principle, and leaves the fibrin. 



* Ann. de Ch. et Ph. xlviii., 321. t Records, i., p. 31. 



