COMBATING PARASITIC BACTERIA. 187 



attempt to find specific drugs for specific diseases, 

 and it is at least doubtful whether many such will 

 ever be found. The nearest approach to it is qui- 

 nine as a specific poison for malarial troubles. 

 Malarious diseases are not, however, produced by 

 bacteria but by a microscopic organism of a very 

 different nature, thought to be an animal rather 

 than a plant. Besides this there has been little 

 or no success in discovering specifics in the form 

 of drugs which can be given as medicines or inocu- 

 lated with the hope of destroying special kinds of 

 pathogenic bacteria without injury to the body. 

 While it is unwise to make predictions as to future 

 discoveries, there seems at present little hope for 

 a development of curative medicine along these 

 lines. 



VIS MEDICATRIX NATURAE. 



The study of bacterial diseases as they pro- 

 gress in the body has emphasized above all things 

 the fact that diseases are eventually cured by a 

 natural rather than by an artificial process. If a 

 pathogenic bacterium succeeds in passing the 

 outer safeguards and entering the body, and if it 

 then succeeds in overcoming the forces of resist- 

 ance which we have already noticed, it will begin 

 to multiply and produce mischief. This multi- 

 plication now goes on for a time unchecked, and 

 there is little reason to expect that we can ever 

 do much toward checking it by means of drugs. 

 But after a little, conditions arise which are hos- 

 tile to the further growth of the parasite. These 

 hostile conditions are produced perhaps in part 

 by the secretions from the bacteria, for bacteria 

 are unable to flourish in a medium containing 

 much of their own secretions. The secretions 



