* 



218 THE BLOOD. 



The entire mass of the blood- globules, in proportion to the rest 

 of the circulating fluid, can only be approximately measured by 

 the eye in a microscopic examination. In ordinary analyses the 

 globules are usually estimated as amounting to about fifteen per 

 cent., by weight, of the entire blood. This estimate, however, refers, 

 properly speaking, not to the globules themselves, but only to their 

 dry residue, after the water which they contain has been lost by 

 evaporation. It is easily seen, by examination with the microscope, 

 that the globules, in their natural semi-fluid condition, are really 

 much more abundant than this, and constitute fully one-half the 

 entire mass of the blood that is, the intercellular fluid, or plasma, is 

 not more abundant than the globules themselves which are sus- 

 pended in it. When separated from the other ingredients of the 

 blood and examined by themselves, the globules are found, ac- 

 cording to Lehmann, to present the following composition : 



COMPOSITION OF THE BLOOD-GLOBULES IN 1000 PARTS. 



Water 688.00 



Globuline 282.22 



Haematine ........... 16.75 



Fatty substances 2.31 



Undetermined (extractive) matters 2.60 



Chloride of sodium ........ 



" potassium ........ 



Phosphates of soda and potassa ...... 



Sulphate " " 



Phosphate of lime 



" " magnesia ....... 



1000.00 



The most important of these ingredients is the globuline. This 

 is an organic substance, nearly fluid in its natural condition by 

 union with water, and constituting the greater part of the mass of 

 the blood- globules. It is soluble in water, but insoluble in the 

 plasma of the blood, owing to the presence in that fluid of albumen 

 and saline matters. If the blood be largely diluted, however, the 

 globuline is dissolved, as already mentioned, and the blood-globules 

 are destroyed. Globuline coagulates by heat; but, according to 

 Kobin and Yerdeil, only becomes opalescent at 160, and requires 

 for its complete coagulation a temperature of 200 F. 



The hsematine is the coloring matter of the globules. It is, like 

 globuline, an organic substance, but is present in much smaller quan- 

 tity than the latter. It is not contained in the form of a powder, 



