704 



end of the diastole or the pause. This was already explicitly discussed 

 by me with regard to veratrine and digitalis to which I refer here ^). 

 The same holds likewise for antiarine, about which I intend to 

 publish a more extensive communication. We can then convert again 

 the normal ventricle-rhythm into the hahed one by applying an 

 extra-stimulus to the auricle or to the ventricle-basis in the beginning 

 of the ventricle-systole. 



During the normal rhythm the impulse is transmitted slower 

 through the ventricle than during the halved rhythm of the ventricle. 

 It is of course clear that the conductivity inside the ventricle 

 during the normal ventricle-rhythm, in which in the same time 

 twice as many systoles of the ventricle take place than during the 

 halved ventricle-rhythm, is worse than af"ter the halving of the 

 ventricle-rhythm. 



In Fig. 6 I reproduce an example of such an artificial modifi- 

 cation of the rhythm. In the beginning of the fig. (the first two 

 ventricle-sj'stoles) the rhythm of the ventricle is halved. After every 

 large ventricle-systole occui's another extremely little abortive 

 ventricle-systole, the little triangular electrograms of which are 

 indicated by an a. Both these little ventricle-systoles of the halved 

 rhythm show little negative T-oscillations, and the line of connection 

 between the R- and the T-oscillation lies just below the position of 

 rest of the string. At the rising of the signal the ventricle-basis 

 receives an extra-stimulus towards the end of the pause, after which 

 a great ventricle-systole follows. Thereupon the normal rhythm of 

 the ventricle is restored. The first ventricle-systole of this noi'mal 

 ventricle-rhythm succeeds still after a rather long pause, so that the 

 impulse-transmission through the ventricle is now only unim- 

 portantly retarded (compare the width of the R-oscillation of this 

 systole with that of the two preceding systoles of the halved ventricle- 

 rhythm). This slight retardation is however already expressed in an 

 enlargement of the negative T-oscillation and in a descent of the 

 line of connection between the R-oscillation and the T-oscillation. 

 The pauses between the succeeding ventricle-systoles are considerablj' 

 shortened, and now the width of the R-oscillations has remarkably 

 increased. The ventricle-electrograms show likewise large negative 

 T-oscillations, and the lines of connection between the R- cind the 

 T-oscillations have descended considerably, and are gradually con- 

 verted into the T-oscillations. 



In Fig. 7 the halved rhythm of the ventricle was by an 



1) Arch. Néerl. de Physiol, loc. cit. 



