1076 
a. couple of hours and longer, all systoles; this aim can be better 
reached with one lever than with two. By doing so I had to watch 
only one friction on the smoked paper, when noting down the 
systoles of the auricles and ventricles, so that their succession, with 
regard to time, can be better estimated and we obtain a better 
survey of the whole reproduction. The curves were noted down by 
the lever on an endless smoked paper which was wound round 
three kymographia; the motion was obtained in the usual way by 
making one of these apparatuses turn, whilst the two others with 
unserewed axes followed the revolution. In this way I could note 
down during two hours and a half after the poisoning all the curves 
and obtained the entire reproduction of the poisoning; in order to 
make a comparison first about one hundred systoles of the unpoi- 
soned heart were reproduced. To a maximum of ten drops of 1 °/, 
acetas veratrini were then injected into the abdominal cavity. About 
10 minutes after the injection the systoles became larger and wider, 
the a-v-interval increased, the electric irritability of the ventricle 
diminished. When I fixed before the poisoning the weakest stimu- 
lation with which I could obtain an extra-systole after the beginning 
of the diastole, I had, after the poisoning, either to strengthen it or 
to apply it later, in order to obtain the same effect. This continued 
till in the end, during the whole diastole, I did not obtain any 
effect on the ventricle not even with the strongest stimulation. 
In this stage of the poisoning I observed quite a new phenomenon : 
at the end of the diastole no extrasystole was obtained after irri- 
tation, but a pause of the ventricle. The duration of this pause 
was always of such a nature that, added to the duration of the 
preceding heartperiod, they amounted together to two heart-periods. 
The pause began with an extrasystole of the auricle. The auricle 
was now irritable indeed, which was promoted by lengthening the 
a-v-interval. This extrasystole of the auricle was caused by retro- 
gressive transmission of stimulation or with strong stimulation by 
current-loops. 
The next-following irritation coming from the sinus venosus finds 
then the auricle refractory. The result is that one auricle- but likewise 
one ventricle-systole falls out of the normal rhythm, and so an 
extra pause takes place. Now it is remarkable to see, how strongly 
widened the postcompensatory systoles are after these extra-pauses 
without extra-systoles. This fact is indeed entirely in accordance 
with the law on the conservation of the energy of the heart 
(LANGENDORFF). In my case indeed pause of the ventricle 1. e. rest 
of the ventricle appears without preceding extra-systole. The condi- 
