414 



SCIENCE. 



[N. S. Vol. IV. No. 91. 



constituents of the atmosphere were thus 

 shown to be of themselves incapable of in- 

 ducing any organic development in yeast 

 water. 



Such is a sample of the many well- de- 

 vised experiments by which he carried to 

 most minds the conviction that, as he ex- 

 pressed it, ' la generation spontanee est une 

 chimere,' and that the humblest and minut- 

 est living organisms can only originate by 

 parentage from beings like themselves. 



Pasteur pointed out the enormous im- 

 portance of these humble organisms in the 

 economy of nature. It is by their agency 

 that the dead bodies of plants and animals 

 are resolved into simpler compounds fitted 

 for assimilation by new living forms. 

 Without their aid the world would be, as 

 Pasteur expresses it, encombre de cadavres. 

 They are essential not only to our well-be- 

 ing, but to our very existence. Similar 

 microbes must have discharged the same 

 necessary function of removing refuse and 

 providing food for successive generations of 

 plants and animals during the past periods 

 of the world's history ; and it is interesting 

 to think that organisms as simple as can 

 well be conceived to have existed when life 

 first appeared upon our globe have, in all 

 probability, propagated the same lowly but 

 must useful offspring during the ages of 

 geological time. 



Pasteur's labors on fermentation have 

 had a very important influence upon sur- 

 gery, I have been often asked to speak on 

 my share in this matter before a public 

 audience; but I have hitherto refused to do 

 so, partly because the details are so entire- 

 ly technical, but chiefly because I have felt 

 an invincible repugnance to what might 

 seem to savor of self-advertisement. The 

 latter objection now no longer exists, since 

 advancing years have indicated that it is 

 right for me to leave to younger men the 

 practice of my dearly loved profession. 

 And it will perhaps be expected that, if I 



can make myself intelligible, I should say 

 something upon the subject on the present 

 occasion. 



ISTo thing was formerly more striking in 

 surgical experience than the difference in 

 the behavior of injuries according to wheth- 

 er the skin was implicated or not. Thus, 

 if the bones of the leg were broken and the 

 skin remained intact, the surgeon applied 

 the necessary apparatus without any other 

 anxiety than that of maintaining a good 

 position of the fragments, although the in- 

 ternal injury to bones and soft parts might 

 be very severe. If, on the other hand, a 

 wound of the skin was present, communi- 

 cating with the broken bones, although the 

 damage might be in other respects compari- 

 tively slight, the compound fracture, as it 

 was termed,- was one of the most danger- 

 ous accidents that could happen. Mr. 

 Syme, who was, I believe, the safest sur- 

 geon of his time, once told me that he was 

 inclined to think that it would be, on the 

 whole, better if all compound fractures of 

 the leg were subjected to amputation, with- 

 out any attempt to save the limb. What 

 was the cause of this astonishing difierence ? 

 It was clearly in some way due to the ex- 

 posure of the injured parts to the external 

 world. One obvious effect of such exposure 

 was indicated by the odor of the discharge,, 

 which showed that the blood in the wound 

 had undergone putrefactive change by 

 which the bland nutrient liquid had been 

 converted into highly irritating and poison- 

 ous substances. I have seen a man with 

 compound fracture of the leg die within 

 two days of the accident, as plainly poisoned 

 by the products of putrefaction as if he had 

 taken a fatal dose of some potent toxic drug. 



An external wound of the soft parts might 

 be healed in one of two ways. If its sur- 

 faces were clean cut, and could be brought 

 into accurate apposition, it might unite 

 rapidly and painlessly ' by the first inten- 

 tion.' This, however, was exceptional. 



