MEMBERS OF THE BRITISH MEDICAL ASSOCIATION 259 



you will be constantl}' liable to relax in your precautions. I have seen, for 

 instance, a gentleman, anxious to carry out the antiseptic treatment completely, 

 take out a large loose cartilage from the knee-joint under the spray, using at 

 the outset instruments which had been purified by lying in a solution of carbolic 

 acid ; but in the course of the operation, I observed him take a pair of forceps 

 which seemed better adapted for his purpose than any which he had so prepared, 

 and simply dip them for an instant into the antiseptic lotion, and then plunge 

 them into the interior of the joint. Now, Gentlemen, was that doing the treat- 

 ment justice ? Between the teeth of those forceps there were probably portions 

 of dirt. Give the carbolic acid lotion time, and it would penetrate this dirt, 

 greas}^ though it might be ; but it cannot do so in a moment ; and nothing was 

 more likely than that some portion of this dirt would come off from the forceps 

 and remain in the joint, and induce putrefaction there. I have known of a 

 gentleman with every anxiety to carry out antiseptic treatment, exploring 

 the wound in a case of fracture of the skull, and, the probe happening to fall to 

 the ground, it was taken up from the dusty floor, and immediate^ passed into 

 the depths of the wound. Now, Gentlemen, that was but courting failure. 

 What more likely than that some of the septic dust, which certainly was brought 

 up adhering to the bloody probe, should pass into the wound without ha\-ing 

 been sufficiently acted on by the spray in the moment of transit, and, mingling 

 with the blood in the interior, be there protected for the future by the blood- 

 clots from the antiseptic influence of the dressings, and induce putrefaction ? 

 If we could see the septic material upon the instrument as distinctly as we 

 could see green paint in contrast with the red blood, then of course we should 

 say. We must wash off this green poison ; but because we cannot see it ^^•ith 

 the physical eye, we are always liable to make mistakes through neglect of using 

 proper precautions ; and I am more and more persuaded, the longer I practise 

 antiseptic surgery, that the chief essential to success is a thorough conviction 

 of the reality of the presence of the septic matter on all objects in the \\orld 

 around us. Through the kindness of the President of the Physiological Section, 

 I hope to have the opportunity of demonstrating some facts which I believe 

 will tend to convince you that the septic ferments are, like those of the alcoholic 

 fermentation, living organisms — that they arc analogous to the yeast plant. 

 But whether you believe or do not believe that they are li\-ing, it is as certainly 

 demonstrated scientifically as it is certain we are here, that these ferments do 

 exist. If we do not bear that in lively remembrance, we shall be constantly 

 making mistakes. 



[Mr. Lister then proceeded to perform the operation. Some small arteries, 

 which bled in the incision, were secured with fine prepared catgut, and the 



