PART I. 



DISEASE GERMS 



THEIR 



SUPPOSED NATURE. 



IOISONOUS matter exists in different states. 

 There are poisonous solids, poisonous liquids, 

 and poisonous gases. These kill man and the 

 higher animals in many different ways. Some 

 destroy the textures of the body ; others interfere with 

 the due discharge of function on the part of certain 

 tissues and organs, the proper action of which may be 

 necessary to the living state ; while others again 

 actually kill the living matter of the body ; and of 

 these there are poisons which act as soon as they 

 pass into the organism, almost instantaneously, and 

 poisons which produce their deleterious effect very 

 slowly. There are again substances which act as 

 poisons to every known kind of living matter, while 

 certain principles of vegetable origin which destroy 

 some vertebrate animals.with unerring certainty may 

 be eaten freely by others, and even constitute their 

 ordinary food. 



Of all the poisons which cause the death of man, 

 the most subtle and the most difficult to isolate and 



B 



