35 
shortest length of time, and if starvation were a factor it is evident 
that they should have lived the greater period of time. 
Again, it may be argued that death naturally resulted more quickly 
from the toxic action of the greater amount of acetanilide consumed 
by those mice which ate the most cake. But the figures do not bear 
out this assumption. In the first place, of the two lots receiving 
caffeine that receiving the smaller amount lived the longer, and yet 
this lot consumed more cake, and therefore acetanilide in the ratio of 
62 to 69. In the second place, the length of time until death of the 
acetanilide control mice and the acetanilide mixture (0.020 gram 
caffeine) mice are not in even an approximate ratio to the amount 
of cake eaten: Ratio of cake eaten, 100 to 119; ratio of days until 
death, 100 to 166. The conclusion seems unavoidable, therefore, 
that caffeine adds to the toxicity of acetanilide. 
TOXICITY OF ACETANILIDE AND SODIUM BICARBONATE 
MIXTURES. 
Other experiments were carried out in which mice were fed cakes 
containing sodium bicarbonate mixed with acetanilide. In one 
series, also, caffeine citrate was added to this mixture, giving a com- 
pound acetanilide powder quite closely imitating the United States 
pharmacopoeial preparation of this name. Control mice were given 
sodium bicarbonate 0.020 gram per cake, which amount showed no 
toxic properties. Other controls fed on sodium bicarbonate 0.020 
gram plus caffeine citrate 0.020 gram appeared relatively nontoxic, 
the animals living for 25, 27, 35, and 36 days. The other controls for 
this series of experiments have already been given, this work being 
carried out at the same time and as a part of the series already 
tabulated. Accordingly they will not be recorded again, the only 
data to be repeated appearing in the summary of the following 
experiments : 
Series I. — Acetanilide — caffeine — sodium hi carbonate. 
[Feeding mice acetanilide 0.050 gram + caffeine citrate 0.020 gram + sodium bicarbonate 0.020 gram per 
cake.] 
Date. 
Weight of mice in grams. 
No. 1. 
No. 2. 
No. 3. 
No. 4. 
December 3 
Days. 
16.92 
13. 13 
12.39 
11.53 
Days. 
21.26 
17. 90 
14.58 
Davs. 
18. 15 
15. 15 
12.89 
Days. 
15.84 
15.50 
December 5 
December 7 
December 9 
No. 1, dead December 10, 7 days; No. 2, dead December 9, 6 days; No. 3, dead December 9, 6 days; 
No. 4, dead December 6, 3 days. 
The following table gives the results of giving smaller amounts 
of caffeine. 
