23 
noted, the effect of the poison appears to become less at subsequent 
injections. This is well illustrated by the tracings given in figures 
2 and 3. 
Figure No. 2 shows the effect after 0.600 gram acetanilide and 
0.200 gram caffeine citrate had been injected into the saphenous 
vein; figure No. 3, the effect after an injection of 0.600 gram acetani- 
lide, this tracing immediately following that given in figure 2. It 
may also be inquired whether the caffeine is not responsible for the 
greater weakening shown in figure 2 ; but this is not likely, judging 
from other experiments where the reverse order of injection was used. 
