HYPOTHESES CONCERNING NATURE OF BACTERIOPHAGE 315 



sible, and that this transformation can take place without the intervention of 

 assimilative phenomena, for, assimilation being a physiological charac- 

 teristic of life, a substance which assimilates is alive. 



However, Doerr is consistent. He admits that the bacteriophage is 

 an ultra virus to just the same degree as are the agents of rabies, of vac- 

 cinia, of encephalitis lethargica, and of sarcoma, but in his opinion 

 all of these ultraviruses are simply products elaborated by the diseased 

 cell. The demonstration of the contrary will be given in a later 

 chapter. 



Despite all these new terms, this is but a resurrection of the old theory 

 of Stahl "all bodies brought to a state of putrefaction, readily transmit 

 this state to another body as yet free of corruption." This theory of 

 the multiplication of a principle by communicated motion was supported 

 by Liebig in his famous discussion with Pasteur on the mechanism of 

 fermentation. Pasteur demonstrated experimentally that such a con- 

 ception was false, and it would have seemed that the facts were defi- 

 nitely accepted. Whether it be vital phenomena, or communicated 

 motion, the discussion and the demonstrative experiments are based 

 upon the same ideas; it is simply a case of descending a step or two in 

 the scale as regards the magnitude of the beings involved. 



Whatever may be the words used to clothe the hypothesis that bac- 

 teriophagy is caused by an abnormal inert substance derived from the 

 bacterium, it will always be impossible to explain how it leads to a serial 

 vitiation of the bacterial metabolism without the intervention of a 

 foreign principle, functioning as a cause and perpetuating itself through 

 the passages. Bordet clearly realized the necessity for such an explana- 

 tion, and he provided the only one which can account for the serial 

 vitiation in the bacterial metabohsm without the intervention of a 

 foreign factor. But his explanation does not accord with the facts, 

 hence it can not be accepted. 



In 1923^'*^ I published the arguments refuting the hypothesis, in the 

 form in which it was developed, explaining bacteriophagy as being due 

 to the action of an ''abnormal autolysin." These arguments have 

 since been repeated.^^^-^^-* None of the adherents of this hypothesis 

 have disposed of my objections, nor have they made any mention of 

 them. 



B. Hypothesis of a living abnormal principle, derived from the bacterium. 

 As I stated above, an hypothesis of this nature has not yet been formu- 

 lated. Despite its strangeness, it would not be, however, any more 

 illogical than the preceding. Basically, it would be even less so. 



If, at last, such an hypothesis is advanced, it obviously will be sub- 



