262 THE FLOATING-MATTER OF THE AIR. 



the labours of a man who combines the penetration of 

 the true theorist with the skill and conscientiousness 

 of the true experimenter, and whose practice is one 

 continued demonstration of the theory that the putre- 

 faction of wounds is to be averted by the destruction 

 of the germs of bacteria. Not only from his own 

 reports of his cases, but from the reports of eminent 

 men who have visited his hospital, and from the 

 opinions expressed to me by continental surgeons, do 

 I gather that one of the greatest steps ever made in 

 the art of surgery was the introduction of the anti- 

 septic system of treatment, for which we are indebted 

 to Professor Lister. 



The interest of this subject does not slacken as we 

 proceed. We began with the cherry-cask and beer- vat ;. 

 we end with the body of man. There are persons born 

 with the power of interpreting natural facts, as there 

 are others smitten with everlasting incompetence in 

 regard to such interpretation. To the former class in 

 an eminent degree belonged the illustrious philosopher 

 |Robert Boyle, whose words in relation to this subject 

 lave in them the forecast of prophecy. ' And let me 

 idd,' writes Boyle in his 'Essay on the Pathological 

 *art of Physik,' ' that he that thoroughly understands 

 the nature of ferments and fermentations shall probably 

 be much better able than he that ignores them, to give 

 a fair account of divers phenomena of several diseases 

 (as well fevers as others), which will perhaps be never 

 properly understood without an insight into the doctrine 

 of fermentations.' 



Two hundred years have passed since these pregnant 

 words were written, and it is only in this our day that 

 men are beginning to fully realize their truth. In the 

 domain of surgery the justice of Boyle's surmise has 

 been most strictly demonstrated. But we now pass 



