PHYSIOLOGICAL ACTION OF NITROBENZENE VAPOR ON ANIMALS 457 
This animal showed a slight drop in the red-cell count on the day 
following the fumigation, but this was not sufficiently great to be of any 
importance. The animal developed no very pronounced symptoms of 
poisoning. Dog C, on the other hand, did develop pronounced symptoms, 
and died on the evening of January 23; but Dog C had been fumigated for 
four hours at 18° C. on December 12, 1916, as well as for five hours in 
this experiment. As the result of the first fumigation, however, the animal 
was apparently unharmed, nor was there any change in the blood counts 
following the first fumigation. 
SPECTROSCOPIC EXAMINATION OF THE BLOOD OF ANIMALS POISONED BY 
NITROBENZENE 
A eat was fumigated for a period of three hours at a temperature of 
23.5° C. Shortly after the fumigation a sample of blood was taken, 
diluted with distilled water, and examined spectroscopically. When the 
concentration was just sufficient to cause the oxyhemoglobin bands to 
disappear, a distinct band appeared between C and D, apparently in the 
exact position of the absorption band of methemoglobin. When the 
sample of blood was sufficiently dilute to cause the oxyhemoglobin bands 
to stand out clearly, the absorption band between C and D disappeared 
or was very faint. The undiluted blood was coffee-colored, and the 
diluted blood had the appearance of methemoglobin blood. 
A young dog, a cat, a rabbit, a guinea pig, a chicken, and a pigeon 
were placed together in the fumigation chamber and fumigated for a 
period of three hours at 22.5° C. At the end of the fumigation, a sample 
of blood was taken from each and examined spectroscopically. The cat’s 
blood showed the above-described band faintly; the guinea pig’s blood 
showed the band very distinctly; the samples from the other animals 
failed to show the band. On the following day, blood samples were 
again taken and examined. The sample from the cat showed the band 
more markedly than on the preceding day; the sample from the guinea 
pig did not show the band at all, nor did the samples from any of the 
other animals. 
A sample of blood was taken from a healthy cat and diluted with about 
fifty volumes of distilled water. The diluted blood was then shaken in 
