xin PREVENTIVE MEDICINE 329 



of an army which, on the approach of the enemy, tries 

 to destroy them. Should the number of the attacking 

 host be too large the disease progresses ; if, however, 

 the defending party is in excess, the body retains its 

 normal condition of life. This may well be termed a 

 marvellous revelation of science, or, to quote the words 

 of Lord Lister in his presidential address at the 

 Liverpool meeting of the British Association in 1896, 

 "If ever there was a romantic chapter in pathology, 

 it has surely been that of the story of phagocytosis." 

 The following words conclude MetchnikofPs volume 

 on Immunity : " Within a very short period, immunity 

 has been placed in possession not only of a host of 

 medical ideas of the highest importance, but also of 

 effective means of combating a whole series of maladies 

 of the most formidable nature in man and the domestic 

 animals. Science is far from having said its last word, 

 but the advances already made are amply sufficient to 

 dispel pessimism in so far as this has been suggested 

 by the fear of diseases, and the feeling that we are 

 powerless to struggle against them." l 



To establish an institute in London having similar 

 aims to the Institut Pasteur in Paris was long the wish 

 of many men interested in the progress of preventive 

 medicine. Thanks to the efforts of Lord Lister, 

 Sir Joseph Fayrer, and others, including myself, this 

 wish has been fulfilled, and the Institute of Preventive 

 Medicine in Chelsea is now housed in an appropriate 

 building (see illustration), with appliances and labora- 

 tories not inferior, in many respects, to its sister Insti- 

 tute in Paris. Here researches on questions relating to 

 preventive medicine are carried out by scientific men 

 versed in the several branches of chemistry, bacterio- 



1 For a full account of immunity in infective diseases see MetchnikofPs 

 volume (translation), published by the Cambridge University Press, 1905. 



