866 president's address. 



organization. He stated as his opinion that it would in all 

 probability be found that the plants which produce infectious 

 diseases would be found to pass through different stages of 

 existence, much in the same way as animal parasites have been 

 found to do. 



Since Mr. Macloay read his paper this germ theory as a cause 

 or source of disease has received much attention by scientific men 

 in all parts of the world, and it is truly wonderful what discoveries 

 are being made in scientific medicine as to many diseases and 

 ailments, symptoms which hitherto were quite unexplainable 

 being now proved beyond all doubt to be owing to the presence of 

 fungoid organisms. To illustrate what I mean I cannot do better 

 than make quotations from some of the most recent records on 

 this subject. The theory of vaccination, and the irregular effects 

 of lymph applied to the human subject, are having much light 

 thrown upon them by this same line of study, and as the study 

 of these germ theories advances, it is not unreasonable to hope 

 and expect that several diseases other than smallpox will be 

 checked and mitigated in their ravages on the human body on 

 the vaccination principle. I will first quote from an address by 

 Professor t Liston, delivered before the Pathological Section of 

 the British Medical Association in August, 1880, altering his 

 words occasionally only for the sake of brevity. Nothing could 

 illustrate better the advance of science in this direction, and be 

 brought forward as an argument for the benefits accruing from 

 a study of natural history: — "The relation of micro-organisms 

 to disease is a subject of vast extent and importance. If we 

 compare the present state of knowledge regarding it with that of 

 twenty years ago, we are astonished at the progress which has 

 been made in the interval. At that time Bacteria were little 

 more than scientific curiosities, whether animal or vegetable few 

 people knew or cared ; that they were causes of putrefaction or 

 other fermentive changes was a thing scarcely thought of, and 

 the notion that they had special relations to disease would have 



