DISEASE GERMS IN ANIMAL FLUIDS 

 AND SECRETIONS. 



BEFORE I proceed to describe the characters of the 

 particles suspended in animal fluids, having virulent 

 contagious properties, it is very desirable to draw 

 attention to the minute particles of bioplasm, which 

 may be demonstrated in many specimens of simple 

 exudation. From this subject we shall pass on to the 

 consideration of other forms of " exudation " which 

 possess specific disease-producing properties. We 

 shall find that by a careful microscopical examination 

 of fluids which experience has proved to us have con- 

 tagious properties, facts of great interest are disclosed 

 which have an important bearing on the question of 

 the nature of the poison of contagious diseases. Many 

 such fluids are clear like water, and quite as tran- 

 sparent when examined by the unaided eye only. 

 When we come to subject them to examination with 

 the aid even of the highest powers yet made, although 

 solid particles are detected, and sometimes in great 

 number, we observe nothing peculiar to these fluids 

 alone nothing which would enable us to form any 

 conception of the wonderful properties they possess 

 nothing that would attract the attention of the chance 

 observer, or excite the interest of any one who had not 

 long and carefully studied the matter. Nevertheless, 



