viii INTRODUCTION 



led the opposition to Pasteur. The many famous experiments 

 carried conviction to the minds of scientific men, and destroyec 

 for ever the old belief in spontaneous generation. All alon 

 the analogy between disease and fermentation must have beer 

 in Pasteur's mind; and then came the suggestion: " Whai 

 would be most desirable would be to push those studies fai 

 enough to prepare the road for a serious research into the origii 

 of various diseases." If the changes in lactic, alcohol anc 

 butyric fermentations are due to minute living organisms, whj 

 should not the same tiny creatures make the changes whicl 

 occur in the body in the putrid and suppurative diseases. Witl 

 an accurate training as a chemist, having been diverted in hi* 

 studies upon fermentation into the realm of biology, anc 

 nourishing a strong conviction of the identity between putre 

 factive changes of the body and fermentation, Pasteur was wel 

 prepared to undertake investigations, which had hitherto beer 

 confined to physicians alone. 



The first outcome of the researches of Pasteur upon fermenta- 

 tion and spontaneous generation represents a transformation 

 in the practice of surgery, which, it is not too much to say : 

 has been one of the greatest boons ever conferred upon 

 humanity. It had long been recognised that now and again 

 a wound healed without the formation of pus, that is without 

 suppuration, but both spontaneous and operative wounds were 

 almost invariably associated with that change ; and, moreover, 

 they frequently became putrid, as it was then called infected, 

 as we should say; the general system became involved, and 

 the patient died of blood poisoning. So common was this, 

 particularly in old, ill-equipped hospitals, that many surgeons 

 feared to operate, and the general mortality in all surgical cases 

 was very high. Believing that from outside the germs came 

 which caused the decomposition of wounds, just as from the 

 atmosphere the sugar solution got the germs which caused 

 the fermentation, a young surgeon at Glasgow, Joseph Lister, 

 applied the principles of Pasteur's experiments to their 

 treatment. It may be well here to quote from Lister's original 

 paper in the Lancet, 1867 : " Turning now to the question 



