INTRODUCTION 9 



taken place, when in reality it has not occurred and does not occur 

 when the experiment is properly conducted. 



It should be the duty of some bacteriologist in India to repeat the 

 studies of Hankin, For if the antiseptic substance present in the 

 water of these rivers is actually volatile the action can not be bac- 

 teriophagic in nature. While, on the other hand, if these waters repro- 

 duce the phenomenon with aU of its characteristic features, the bac- 

 tericidal action observed by Hankin must necessarily be referred to 

 bacteriophagy. 



There is another communication* where it is possible that the bac- 

 teriophage may not have been foreign to the results, — results which 

 stimulated certain somewhat sarcastic remarks on the part of Metch- 

 nikoff. It must be admitted that before the era of the bacteriophage, 

 these results might well excite wonder, and, indeed, certain recom- 

 mendations of the authors of the memoir in question may, with reason, 

 seem strange. For they state that bacteriologists should not attempt 

 a confirmation of their experiments, most probably because they them- 

 selves could not interpret the phenomena observed and were unable to 

 repeat them. 



However that may be, here is the passage in the work of Metch- 

 nikofff which refers to these investigations. 



". . . . Emmerich and Low attribute acquired immunity to particular 

 substances which they call "nuclease-immunoproteidine." In accordance with 

 their supposition the bacterial products which are liberated within the body 

 during the period of vaccination, the nuclease, combines with the protein sub- 

 stances of the blood and of the organs, yielding the substance designated by these 

 authors by this very complex name. In their last publication Emmerich and 

 Low go so far as to describe a method for the production of this substance outside 

 of the body, by causing beef blood, or better yet, ground-up spleen, to act upon the 

 nuclease produced by the bacteria in old cultures. t They attribute to this the 

 property of dissolving diverse bacteria, of vaccinating against, and of curing, 

 many infectious diseases. But these authors do not state whether this substance, 

 so very remarkable, is identical or analogous to the antibacterial ferments com- 



* Emmerich, R., and Low, O. — Die klinstliche Darstellung der immunisierenden 

 Substanzen (Nucleasen-Immunproteidine) und ihre Verwendung zur Therapie 

 der Infektionskrankheiten und zur Schutzimpfung an Stelle des Heilserums. 

 Zeitschr. f. Hyg. u. Infektionskrankh., 1901, 36, 9. 



t Metchnikoff, E. — L'Immunite dans les Maladies Infectieuses. pp. 267-68. 



I These words are not underscored in the text of Metchnikoff. I have under- 

 lined them simply to attract the attention of the reader, for purposes which will 

 become apparent shortly. 



