PHYSIOLOGICAL ACTION OF NITROBENZENE VAPOR ON ANIMALS 419 
ments prove nitrobenzene to be a poison; and that a distinction between 
cases of poisoning by nitrobenzene and by hydrocyanic acid can be readily 
made, since the bitter-almond-oil odor due to hydrocyanic acid disappears 
within three or four days—the chemical (hydrocyanic acid) being 
destroyed by contact with the tissues — while the same odor due to nitro- 
benzene wiil persist for several days. 
Ollivier and Bergeron (1863) were led to study the action of nitrobenzene 
from the same standpoint as was Casper — that is, because the drug 
was being extensively used in perfuming toilet soaps and in making 
flavoring extracts. It had also been recommended and used with friction 
for the cure of parasitic affections. These investigators argued that 
since nitrobenzene is readily converted into anilin thru the action of 
nascent hydrogen, it is conceivable that it may be changed into anilin 
in the human body, and anilin is a poison. They gave a guinea pig ten 
or twelve drops of nitrobenzene. The animal, after the initial agitation 
and profuse salivation, remained motionless for some time and then began 
to run about again without showing the least signs of ill effects from the 
drug. To another guinea pig they gave approximately three grams. 
The experiment was begun at 2.12 o’clock, and at 2.40 the animal exhibited 
tremors without excessive convulsions. The heart beats were very faint 
and the respiration was decidedly labored. At 3.10 the animal attempted 
to turn around and fell on its right side. The animal died a few minutes 
before 4 o’clock. 
In another experiment Ollivier and Bergeron exposed the muscles of a 
frog’s leg and placed on them a drop of nitrobenzene. The musclés 
remained sensitive to electric stimulations for a long time and did not 
show the slightest histological changes. The investigators then exposed 
the heart of a living frog and placed a few drops of nitrobenzene on it 
without obtaining the slightest modifications of the heart beat. 
In a fifth experiment Ollivier and Bergeron gave a large, healthy dog 
six drams of nitrobenzene, and in a half hour an additional dose of five 
drams. The experiment was begun at 12.40 0’clock. The animal appeared 
agitated and secreted saliva profusely, but did not vomit. Finally it lay ~ 
down in a dark corner and remained motionless for some time. At 1.20 
it started to howl, appeared excited, and moved its head convulsively. 
Its tongue was hanging out and its eyes were wide and animated. This 
condition lasted for about six minutes, when the dog again became motion- 
