24 
Wlien the caffeine acetanilide mixture followed the plain acetanilide 
the effect of the combined drugs was less instead of greater as in the 
above case. Usually the heart does not become accustomed to the 
poison quite so quickly as in this instance, animals differing very 
widely in this respect. 
Further experiments were carried out in which caffeine citrate 
was injected as soon as the acetanilide effect became pronounced. 
In some instances this procedure showed a possible slight increased 
contraction coincident with the caffeine injection, but almost equally 
