40 STUDIES IN ADVANCED PHYSIOLOGY. 



into themselves under some circumstances foreign particles. 

 Thus if a pus cell from a wound be examined it is usually 

 found to contain many foreign particles, usually bacteria. 

 The corpuscles with their load of included bacteria are then 

 probably sent to the spleen or liver, there disintegrated, and 

 the injurious products eliminated from the body in accord- 

 ance with the regular physiological process. This theory 

 explains in a very interesting way the phenomena of the 

 inflammation of wounds and the gathering of sores. In a 

 wound such as an open cut the bacteria of the air fall at 

 the first exposure and there in the rich nutritious blood 

 begin a course of active development. Soon, however, 

 white corpuscles congregate around the wound, the blood 

 usually following through the openings in the capillaries 

 caused by their migrations, hence the redness. These cor- 

 puscles move regularly towards the infected center, remov- 

 ing the germs as they progress, until finally all of the cor- 

 puscles with their incepted germs meet in the center of the 

 wound there to be, possibly mechanically, pressed out as 

 pus. It is known that wounds entirely protected from germ 

 contamination will not inflame at all, and surgical opera- 

 tions of the most violent character with modern antiseptic 

 improvements may be carried out without any appreciable 

 amount of inflammation. Possibly the added vitality that 

 is supposed to come to these amoeboid cells in their first 

 successful battle enables them to cut a second venture 

 short. That these corpuscles are concerned in the elimina- 

 tion of foreign particles from the blood is probably above 

 question, but that this explains all the phenomena of 

 immunity is another matter. 



The most recent view and possibly the best substan- 

 tiated one of all is the acclimatization theory, which tries 

 to explain that we are immune from a second attack by 

 having become accustomed or acclimated to the poisons in 

 the first attack. To use a not very elegant analogy, it is 

 like the boy who can smoke his second cigar without getting 

 sick, because he has been somewhat hardened by the first 



