THE PRESIDENTIAL ADDRESS. I7 



It is not alone a most fascinating study, throwing a flood of light 

 on most obscure problems of vegetable physiology, but it is also 

 of immense practical importance in the manuring of crops. It is, 

 at least, possible that the mere unintelligent application of the 

 constituents needed for plant life may in some cases do more 

 harm than good by discouraging the efforts of these invaluable 

 living auxiliaries. 



As we get higher in the scale of life, the influence of lower 

 forms becomes of even greater importance. In medicine, 

 instead of being able, as we seemed to have the prospect of being, 

 to regard the body a highly-developed chemical laboratory, the 

 processes of which were more or less analogous to those known 

 in the work-shop of the chemist, we find that health or sickness, 

 life or death, depend to an undetermined degree on the life- 

 history of micro-organisms, the very existence of which we did 

 not guess a few years ago ; it is the culture in the flask of the 

 bacteriologist rather than the re-action in the test-tube of the 

 chemist that tells the secret of disease and its cure. It is the 

 foes within the human frame far more tlian the foes without that 

 imperil it. 



Time would fail to follow out the ramifications of this wide 

 question. I will but remark on the fact that while we are thus 

 constantly meeting fresh proofs of the all-prevailing influence of 

 living organisms, we seein as far off as ever from learning what 

 life is. It certainly is not organic in the sense of depending on 

 the presence of organization ; it is the living " protoplasm " that 

 makes the organization, not the organization that makes the 

 life, but how to express in terms that we can comprehend what 

 is the real difference between living and dead matter is a problem 

 as obscure as ever. 



We do but learn the more we know how little we know and 

 realize how much there is to learn, how much more to believe. 



