312 THIRD JOURNEY TO THE CAUCASUS. 



is not restricted to the objects revealed by our mi- 

 croscopes, but that there are living beings related as 

 regards size to the microbes and bacteria , as these 

 are to us. No scientific objection can be raised to 

 this hypothesis, for the dimensions of molecules are 

 iii any case immeasurably less than living structures 

 of even so low an order. The mysterious process of 

 spontaneous fission , the succeeding immunity , the 

 otherwise inexplicable effect of the introduction of 

 vital products of the disease-causing bacilli into the 

 circulation of a body affected by the same disease, 

 would on this assumption be the obvious consequences 

 of the infection of the disease-generators themselves, 

 and the problem of the future would be, how to pro- 

 duce such an infection, and bring it to the speediest 

 issue, since indeed these secondary disease -generators 

 themselves might also be subject to rapidly developing 

 infectious diseases through microbes of a still lower 

 order. If however not the vital products, but the 

 secondary disease-carriers, of the bacilli are the curative 

 means, the bacilli must first become diseased, before 

 their substance can act remedially. Perhaps herein 

 lies the reason of the unsatisfactory action of Koch's 

 tuberculine , and the present suggestion may be of 

 service in the further investigation of this subject, 

 which is of such vast importance to all mankind. 



In Tiflis we met my brother Charles, who ac- 

 companied us on our further journey to Kedabeg and 

 Baku and back to St. Petersburg. Dr. Hammacher, 

 member of the Imperial Diet, who had formed one 



