550 FRA OMENT8 OF SCIENCE. 



fore, the bacteria die, while their peripheral colleagues 

 continue active. If a bubble of air chance to be enclosed 

 in the film, round it the bacteria will pirouette and wabble 

 until its oxygen has been absorbed, after which all their 

 motions cease. Precisely the reverse of all this occurs 

 with the vibrios of the butyric acid. In their case it is the 

 peripheral organisms that are first killed, the central ones 

 remaining vigorous while ringed by a zone of dead. Pas- 

 teur, moreover, filled two vessels with a liquid containing 

 these vibrios; through one vessel he led air, and killed its 

 vibrios in half an hour; through the other he led carbonic 

 acid, and after three hours found the vibrios fully active. 

 It was while observing these differences of deportment 

 fifteen years ago that the thought of life without air, and 

 its bearing upon the theory of fermentation, flashed upon 

 the mind of this admirable investigator. 



We now approach an aspect of this question which con- 

 cerns us still more closely, and will be best illustrated by 

 an actual fact. A few years ago I was bathing in an 

 Alpine stream, and returning to my clothes from the cas- 

 cade which had been my shower-bath, I slipped upon a 

 block of granite, the sharp crystals of which stamped 

 themselves into my naked shin. The wound was an awk- 

 ward one, but being in vigorous health at the time, I hoped 

 for a speedy recovery. Dipping a clean pocket-handker- 

 chief into the stream, I wrapped it round the wound, 

 limped home, and remained for four or five days quietly in 

 bed. There was no pain, and at the end of this time I 

 thought myself quite fit to quit my room. The wound, 

 when uncovered, was found perfectly clean, uninflamed, 

 and entirely free from matter. Placing over it a bit of 

 goldbeater's-skin, I walked about all day. Toward evening 

 itching and heat were felt; a large accumulation of matter 

 followed, and I was forced to go to bed again. The water- 

 bandage was restored, but it was powerless to check the 

 action now set up; arnica was applied, but it made matters 

 worse. The inflammation increased alarmingly, until 

 finally I had to be carried on men's shoulders down the 

 mountain and transported to Geneva, where, thanks to 

 the kindness of friends, I was immediately placed in the 

 best medical hands. On the morning after my arrival in 

 Geneva, Dr. Gautier discovered an abscess in my instep, at 



