6 president's address. 



of Sir William's will was granted ; but when allowance is made 

 for the vicissitudes which for some time attended the carrying out 

 of the terms of the bequest, and especially for the very serious 

 commercial depression which meantime overtook the communit)', 

 it may fairly be said that throughout the Council has faithfully 

 endeavoured to administer the trust, and that its policy of pro- 

 ceeding slowly and deliberately has been a commendable one. 



As far as the Society is concerned, effect has now been given to 

 the trust. It now rests with the Macleay Bacteriologist and his 

 successors to justify Sir William Macleay 's conviction that it was 

 a desirable thing for the scientific welfare of Australia that the 

 status of Bacteriology should be raised; and that one effective way 

 of accomplishing this was by the appointment of a Bacteriologist 

 untrammelled by official or routine duties, and free to engage in 

 reseai'ch to the full extent of his ability and enthusiasm. 



When, a year ago, I had the honour of addressing you from 

 this chair, I chose for the subject of my remarks during a portion 

 of my address, the somewhat threadbare question of how far 

 mechanical, i.e., physico-chemical, theories are capable of being 

 utilised in the explanation of the phenomena of living activity. 



I A'entured to state the conviction that, in so far as a strictly 

 scientific or natural-historical representation of these phenomena 

 is the object aimed at, this can only be given in terms of physical 

 cause, or mechanism. 



By "strictly scientific or natural-historical explanation," I 

 understand one which is susceptible of verification and of 

 advancement by the objective and experimental methods of 

 scientific procedure, which, as it appears to me, must necessarily 

 operate upon the plane of physical causality. For experimental 

 science, the world-order is conceived as a purely causal nexus. 



It was pointed out at the same time that the validity of any 

 such method of explanation was not absolute, but was relative to 

 a particular aspect of reality; and that its adoption as the charac- 

 teristic working conception of scientific procedure, does not 



