44 ELEMENTS OF HIPPOLOGY. 



Inflammation itself may be described as the perverted 

 nourishment of any part. An injury, the presence of a foreign 

 body, or some abnormal quality of the blood itself chokes the 

 flow of blood through the capillaries and the veins. The heart 

 keeps pumping blood into the affected region, and there is no 

 corresponding drain. This excess of blood is forced through the 

 walls of the capillaries, the tissues become overcharged with it, 

 and the cells and white corpuscles, over-stimulated, begin to 

 multiply. Crowding together, by their own numbers they soon 

 deprive each other of the necessary nourishment, and they die. 

 Other germs, less beneficent than the cells and white corpuscles, 

 if present in the tissues, or if introduced by the cause of the in- 

 flammation, take this occasion to multiply, to destroy other cells, 

 and to die themselves in turn. These dead cells, corpuscles, and 

 germs, suspended in the fluid of the blood, form the whitish, 

 malodorous substance known as pus. 



Figure 31 shows a section of the uninflamed wing of a bat, 

 much less highly magnified than in the preceding cuts. The en- 

 largement is not enough to show the capillaries connecting the 

 arteries and veins. The same spot in the membrane was then 

 wounded with a needle, infiammation set in, and Figure 32 shows, 

 under the same microscope, the enlargement of the capillaries, 

 due to the increased fiow of blood, and the accumulation of the 

 corpuscles. 



Often there is an unnatural accumulation of blood in' any 

 part, caused either by an increased fiow of blood to the part or 

 by an obstruction that prevents the free exit of the blood through 

 the veins from the tissue affected. This is called congestion of 

 the part. In either case there is an increased supply of blood, 



sues; that it is very, very inadequate. The term "corpuscle" is 

 wrongly used to describe all the bodies carried in the fluid of the 

 blood and "cell" to indicate the atoms of which the tissues are built. 

 "Germ" is used to vaguely designate those living micro-organisms 

 that laymen should be willing to dismiss with the knowledge that one 

 must be very wise to understand them. 



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