COMPOSITION OF THE WHITE CORPUSCLES. 



29 



Composition of Human Blood as a Whole. 



Water, 



Solids of these 



Corpuscles, .... 



Serum-albumin, \ 



Serum-globulin, J ' 



Fibrin of Clot (? Fibrinogen), . 



Inorganic Salts (of serum), 



Extractives, .... 



Fatty matters, 

 Gases, 0, C0 2 , N.] 



780 



134 



70 



2-2 V 220 

 6-0 

 6-2 I 

 1-4 J 



24. CHEMICAL COMPOSITION OF THE WHITE CORPUSCLES. Investi- 

 gations have been made on pus cells, which closely resemble colourless blood- 

 corpuscles. They contain several proteids ; alkali-albuminate, a proteid which 

 coagulates at 48 C, an albuminate resembling myosin, paraglobulin, peptone, and a 

 coagulating ferment ; nuclein in the nuclei ( 250, 2), glycogen ( 252), lecithin, 

 cerebrin, cholesterin, and fat. 



100 parts, by weight, of dry pus contain the following Salts : 



Earthy Phosphates, . . 0'416 I Potash, 0-201 



Sodic Phosphate, . . . 0'606 | Sodic Chloride, . . . 0'143 



25. BLOOD-PLASMA AND ITS RELATION TO SERUM. The unaltered 

 fluid in which the blood-corpuscles float is called blood-plasma, or liquor sanguinis. 

 This fluid, however, after blood is withdrawn from the vessels, rapidly undergoes a 

 change, owing to the formation of a solid fibrous substance fibrin. After this 

 occurs, the new fluid which remains, no longer coagulates spontaneously (it is 

 plasma, minus the fibrin-factors), and is called serum. Apart from the presence of 

 the fibrin-factors, the chemical composition of plasma and serum is the same. 



[When blood coagulates, Table I. shows what takes place, while Table II. shows what occurs 

 nvhen it is beaten : 



Coagulation. 

 Blood. 



I 

 Plasma. 



I 

 Corpuscles. 



I 



Serum. 



Fibrin-factors. 



II. 



When beaten. 



Blood. 



Plasma. 



Corpuscles. 



Fibrin-factors. 



Blood-Clot. Fibrin. Defibrinated Blood. 



Plasma is a clear, transparent, slightly thickish fluid, which, in most animals 

 (rabbit, ox, cat, dog), is almost colourless; in man it is yellow, and in the horse 

 citron yellow. 



26. PREPARATION OF PLASMA. (A) Without Admixture. Taking 

 advantage of the fact that plasma, when cooled to outside the body, does not 

 coagulate for a considerable time, Briicke prepares the plasma thus : The blood of 

 the horse (because it coagulates slowly, and its corpuscles sink rapidly to the bottom) 

 is received, as it flows from an artery, into a tall narrow glass, placed in a freezing- 

 mixture, and cooled to 0. The blood remains fluid, the coloured corpuscles 

 subside in a few hours, while the plasma remains above as a clear layer, which can 

 be removed with a cooled pipette. If this plasma be then passed through a cooled 

 filter, it is robbed of all its colourless corpuscles. [Burdon-Sanderson uses a vessel 

 consisting of three compartments the outer and inner contain ice, while the blood 

 is caught in the central compartment, which does not exceed half an inch in 

 diameter.] The quantity of plasma may be roughly (but only roughly) estimated 

 by using a tall, graduated measuring-glass. If the plasma be warmed, it soon 



