DISEASE GERMS CAUSE DEATH. 



225 



had an opportunity of demonstrating every degree of 

 capillary obstruction in the pulmonary tissue. In the 

 early stages of this most fatal form of fever, boils and 

 other evidences of complete capillary obstruction over 

 a limited extent of tissue are often observed, but these 

 are too frequently followed by more extensive general 

 capillary plugging, which is necessarily fatal. 



Of the manner in which an Organism may be "pro- 

 tected" from other attacks of the same Contagious 

 Disease. Of all the problems I have ventured to 

 touch upon in my book, this is by far the most difficult. 

 It is one which has been as yet little considered. In- 

 deed, until a clear idea of the nature and mode of 

 action of disease germs had been formed, the con- 

 sideration of such a question could not have been 

 undertaken with much prospect of success. 



Certain physicists and chemists, satisfied that all 

 the phenomena of the universe are to be explained 

 by physics and chemistry, would, of course, dismiss 

 this and other such questions in a sentence or two 

 about collocations and physical attractions, mole- 

 cular properties and evolutional heterogenity, and 

 assure the public that they understood all about it, 

 although they are quite unable to explain what they 

 mean by the long words they employ. A phrase- 

 ology which is eminently fitted for conveying infor- 

 mation about the actions and reactions of lifeless 

 particles upon one another may become utterly devoid 

 of meaning when applied to living things. As long 



