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of the science of bacteriology by his work with the bacteria—which 
include plants of the greatest importance in medicine. In this case, 
however, these plants were shown to be usually the cause rather 
than the cure, of disease. 
The present century has already witnessed a great increase in 
our knowledge of the nature and etiology of disease as well as of 
curative agents, including the use of serums and antitoxins, and 
the introduction of substitutes for remedies derived from plants, 
such, for example, as atabrine for quinine. Ephedrine (Ma 
Huang), an alkaloid derived from the Chinese plant, Ephedra 
equisetina and other species, has also come into general use follow- 
ing the studies of Dr. K. K. Chen and associates at the Peking 
Union Medical College in 1924. 
In all this nixture of fact and fancy, of superstition and good 
ung forward and sliding back, by the method of trial 
_— 
sense, of pus 
and error, one thing emerges crystal clear. Looking down the 
perspective of all these centuries of record, and before, there /as 
been a definite and sustained progress toward more, and more ac- 
curate, knowledge, and greater efficiency. Moreover, it seems to 
be a constantly accelerated progress, that is, faster and faster with 
each passing year. Obviously, man is still struggling. But if we 
are to judge by the past, he will some day come through to a clear 
understanding and perfect knowledge. 
