PRESIDENTIAL ADDRESS FERGUSSON. CXV11 



being taken advantage of in the Widal test for typhoid in- 

 fection. A vast amount of work was done on the effect of 

 introducing into the blood stream foreign elements such as 

 blood corpuscles of other species, albuminous bodies, e.g., 

 serums, extract of muscle, etc. These developed antibodies, 

 and we have now the biological blood test, precipitin test 

 for flesh, and many others. Here we have evidence of a large 

 number of reactions chemical reactions between bodies 

 of whose composition and properties little is known. To 

 investigate such is the work of a new individual, the biolog- 

 ical chemist. There lies open to him a new and immense field 

 in the chemistry and physics of life, in the science of the cell, 

 with its protoplasmic contents and their activities. 



The biochemist is a new specialist who must have a long 

 and varied training, for so co-related are the sciences that he 

 who would interpret aright the phenomena he observes must 

 have the broadest foundation on which to build. 



With some point of kinship to the toxins we have as cell 

 products the Enzymes. The enzmyes of digestion and fer- 

 mentation have long been known and investigated, and a host 

 of enzymes are classed as catalysers, and much work has been 

 done on the dynamics of reaction and the effect of activating 

 and inhibiting agents. 



Being catalysers, accelerators of reaction, they need only 

 be, and are, present in small quantities, but they have a most 

 important part in synthesis and degradation of organic matter 

 in the life cycle. Up to the present it cannot be said that 

 any enzyme has been obtained in a state of purity. Methods 

 of purification employed destroy activity for some reason or 

 other, so that little is known of their constitution beyond a 

 general analysis. 



Work is being done on the physics of the cell, on surface 

 tension, osmotic pressure, etc. About two years ago Prof. 

 MacCallum by means of a microchemical stain was able under 

 the microscope to show the distribution of Potassium in cells, 



