for the year 1878. xxv 



surgical diagnosis has already been demonstrated. While a 

 wonderful future is predicted for the phonograph, at present, 

 if we except its power of giving a peculiar graphic repre- 

 sentation of multiple and complex sounds, it cannot be said 

 to be out of the category of scientific toys. 



That branch of biological science which has become ioiown 

 as the germ theory still justly occupies the attention of 

 many cf the foremost investigators in physics, physiology, 

 and pathology, while diligent inquiries are also being made 

 by many less known but earnest seekers after the truth. 

 The burning part of the question a few years ago was, 

 whether or not the lower class of organic life was ever pro- 

 duced by spontaneous generation ; this, I think, may be 

 considered to be finally answered in the negative by the 

 conclusive results of the experiments of Tyndall, Cohn, and 

 others. Some of these results were described by our vice- 

 president, Mr. Foord, at a former conversazione, in which it 

 was demonstrated that a temperature of 212 deg. Fahrenheit, 

 long continued, completely sterilised inoculated solutions. 

 The old maxim, Ex nihilo nihil Jit, therefore, still holds true 

 in the arcana of nature. The most important and interest- 

 ing phase this question has more recently assumed has 

 reference to the influence exercised by low forms of organic 

 life upon the human body in health and disease. Professor 

 Tyndall's recent experiments show how difiicult it is to free 

 the air we breathe and live in from the myriads of microscopic 

 and ultra-microscopic germs, plants, and animals that pollute 

 it, but that, with proper precautions, it is not only possible 

 to do so, but to keep it so. In air thus thoroughly divested 

 of all germs and organic life, animal and vegetable sub- 

 stances which we have generally regarded as possessing 

 inherent properties of decay and corruption are found, when 

 once sterilised by boiling, to remain pure and unchanged for 

 years. There now remains little doubt, therefore, that the 



