ELECT RO-PH YSIOLOG Y 



733 



longitudinal surface and cross-section, and that a current of action 

 is caused by excitation. Setschenow stated that when the medulla 

 oblongata of the frog was connected with a galvanometer, spon- 

 taneous variations occurred which he supposed due to periodic 



FIG. 284. HUMAN ELECTRO CARDIO- 

 GRAM (STRING GALVANOMETER), 



(ElNTHOVEN). 



Led off from the two hands, i mm. 

 of the abscissa corresponds to o'oi 

 second. 



FIG. 285. HUMAN ELECTRO-CARDIO- 

 GRAM (STRING GALVANOMETER), 



(ElNTHOVEN). 



Led off from right hand and left 

 foot. 



o,iSec. 



FIG. 286. SCHEMATIC REPRESENTATION OF ELECTRO-CARDIOGRAM (STRING 

 GALVANOMETER), (EINTHOVEN). 



Five points are lettered at which the curve changes sign. P. corresponds to 

 the auricular contraction ; the other four are included in the ventricular cycle. 



FIG. 287. ELECTRO-CARDIOGRAM FROM MAN (STRING GALVANOMETER), (LEWIS). 



From a case of paroxysmal tachycardia. The heart-rate was 200 a minute. 



The upper notched line is the time-trace in one-fifth seconds. 



functional changes in its grey matter. Gotch and Horsley have 

 made elaborate experiments on the spinal cords of cats and mon- 

 keys. Leading off from an isolated portion of the dorsal cord to 

 the capillary electrometer, and stimulating the " motor " region of the 



