112 BIOLOGY AXD THE STATE H 



APPENDIX 



(A) 



The six years which have passed since this address 

 was delivered have been remarkable for the extra- 

 ordinary advances in our knowledge of the Bacteria 

 and their relation to disease. In another paper (No. 

 III.) I have given some account of M. Pasteur's dis- 

 coveries in regard to rabies and hydrophobia. In the 

 Pasteur Institute in Paris Dr. Koux and other in- 

 vestigators have greatly advanced our knowledge of 

 the action of Bacteria in tuberculosis, in diphtheria, 

 and other diseases. It now appears that the most 

 hopeful method of combating the attacks of disease- 

 producing Bacteria is not to attempt to introduce 

 drugs into the infected patient which shall directly 

 poison the Bacteria, but rather to endeavour to assist 

 those natural processes in the body by which intrusive 

 Bacteria are normally destroyed. Elias Metschnikoff 

 has shown that the amoeboid corpuscles of the blood 

 and other tissues are special agents or scavengers for 

 the destruction of such intrusive bodies as Bacteria. 

 His theory is that by accustoming these corpuscles, 

 which he calls ''phagocytes," to tolerate a weak form 

 of the poison produced by pathogenic Bacteria, we 



