CHAPTER XVI. 



Specific Diseases. 



Are those which arise from a certain germ or poison, which 

 being introduced into the system produces the same disease as 

 that affecting the subject from which the germ or poison origin- 

 ated. For instance, tuberculosis (consumption) was proven by 

 Koch to be due to the presence in the tissues of the body of a 

 rod-shaped micro-organism, termed by him the bacillus tuber- 

 culosis. He also proved that tuberculosis did not exist without 

 the presence of this special bacillus, and that the introduction of 

 these baccilli into healthy siibjects produced tuberculosis and no 

 other disease. This also holds good for all specific diseases. 

 Every specific disease has its specific germ, which if introduced 

 into the animal economy through some channel (by the mouth, 

 inoculation, respired air, etc.,) and finding suitable surroundings 

 to develop in, quickly reproduces itself and poisons the blood 

 either by direct destruction of the red blood corpuscles or by pro- 

 ducing an alteration of the normal blood constituents, which soon 

 causes the death of the affected subject; and vice versa, should 

 the system be strong enough to overcome the freshly introduced 

 germs, the surroundings not being suitable for their reproduction 

 and development, they soon perish, in many cases without affect- 

 ing any constitutional disturbance. 



Germs, then, are the cause of all specific diseases, and the 

 question arises, what are germs? They are vegetable micro- 

 organisms, rounded, ovoid, or spiral in shape, which possess the 

 property of reproducing themselves in the animal economy. 

 Their waste products termed the ptomaines being chiefly re- 

 sponsible for the damage and destruction they cause. They are 



