550 FRAGMENTS 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, uuinflamed, 
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 
