22 
the deleterious effect on the dog’s heart produced by a 1-gram dose 
of acetanilide. 
The gradual decrease in the action of acetanilide makes the deter- 
mination of possible antagonistic effects of caffeine and sodium 
bicarbonate somewhat difficult. As has been noted, the effect of 
acetanilide is to lessen the contractile power of the heart, and caffeine 
should prevent this symptom if it acted as an antagonist. A mix- 
ture of the two drugs was injected, but in no case was the decrease 
in the systolic phase prevented — whether it may have been less 
pronounced is of course difficult to determine since, as has been 
