AND PHYSIOLOGY. 



221 



Crystals from Human Blood. 



of the breath of the ani- Fig. 224. 



mal from which it is 

 taken. It penetrates 

 every solid tissue of the 

 system, as may be known 

 by puncturing any part 

 of the body with even a 

 pin, when blood is sure 

 to follow. If it be ex- 

 amined with a micro- 

 scope when freshly 

 drawn, it appears to be 

 made up of a transparent 

 liquid called the Serum 

 or Plasma, and a num- 

 ber of minute circular bodies, mostly of a red color, called 

 corpuscles, or minute bodies. This fluid is found, on analy- 

 sis, to be made up of water, albumen, fibrin, and several salts, 

 some of which are found in crystals, as is seen in the cut. 

 After it has been drawn from the body a considerable time, it 

 separates into a thickened mass called Coagulum, made up of 

 Fig. 225. fibrin and the corpuscles, while the 



serum with the albumen still remains 

 as a transparent liquid. The Red 

 Corpuscles prove to bj flattened discs 

 with both surfaces slightly concave, 

 and measuring about 3 sVoth of an 

 inch in diameter, and are in reality 

 nothing but a cell, that is a bag or 

 sac containing a fluid composed of the 

 two proximate principles globuline and 

 hematine. Besides the red corpuscles, there exists another 

 kind in the blood known as the White or Colorless Corpus- 

 cles. They are by no means so abundant, when the body is 



What is its appearance under the microscope ? How does it conduct itself after stand- 

 ing a while in an open vessel? Describe the Eed Corpuscles. Describe the White Cor- 

 puscles. 



Red Corpuscles of Human 

 Blood. Seen on the Surface, 

 c, Seen in Profile. 5, Seen in 

 a Roll Magnified 400 Diameters. 



