Electromotive Phenom. of the Mammal. Heart. 26.3 



negative state at ili at point, the rise and fall of the cuiTe being, ren- 

 dered more gradual, and conversely the effect of warming was to 

 shorten the duration of negativity and render more abrupt tlie rise 

 and fall of the curve. Thus, if we consider the electrical changes at 

 the exact points A and JB only, we get the following result (Fig. 2). 

 A and B are supposed to be at the same temperature. 



Fig. 2. 



The curve marked a is the coiurse of negativity at A, and that 

 marked b, that at B. The effect of tliis on the electrometer will be 

 the following. (Fig. 3.) 



i«,.,„ '' 



A 



A m if 







Fig. 3. 



If however, the point A is cooled, the negative state there is slow- 

 ed and diminished in amplitude, so that the two variations would 

 now be represented by Fig. 4. 



This would give a triphasic variation (Fig. 5) and this as we 

 saw was one of the stages we obtained when cooling the base of 

 the heart. 



But the explanation will not account for the complete reversal 



