ELECTROMOTIVE PHENOMENA IN GLANDS. 515 



electrical phenomena of the salivary glands of the dog and 

 cat, and concluded that while the variation upon excitation 

 is diphasic in all cases (with, perhaps, the exception of the 

 parotid of the dog on sympathetic excitation), the phase in 

 the ascendant is determined by the predominance of one of the 

 two factors in the hypothesis of Heidenhain in the cell action, 

 viz., flow of fluid, and elaboration of organic constituents. 



Flow of fluid they hold is marked by outgoing, cell 

 metabolism by ingoing current. Thus excitation of the 

 chorda of the dog's submaxillary gives a predominant out- 

 going phase easily cut out by atropine, while excitation of 

 the sympathetic is marked by ingoing current, and the 

 variation is refractory to atropine. In the case of the cat, 

 as a rule, the "chorda saliva" is more viscid than that 

 from sympathetic excitation, and in the latter case the out- 

 going current is more prominent, while though both phases 

 are distinct with the chorda on the electrodes, the ingoing 

 phase is far more marked than is the case with the dog. 

 In the exceptional cases, where the "sympathetic saliva" 

 of the cat's submaxillary gland is very viscid, a marked 

 ingoing current makes itself evident. 



It is possible even for a galvanometer reading to indicate 

 an outgoing current, pure and simple (in, say, the dog's 

 submaxillary, on excitation of the chorda), though abolition 

 or reduction of the outgoing phase by atropine may reveal 

 the existence of a contemporaneous ingoing current that 

 had previously been swamped. 



The net conclusion arrived at by these observers is 

 that the outgoing secretion current, so marked in free flows 

 of saliva, is electro-capillary in origin, whether produced in 

 the basement membrane or "the cells, while the ingoing 

 secretion current, appertaining more especially to cases of 

 viscid secretion, is produced during the metabolic cell events 

 necessitated in the elaboration of the organic constituents 

 of the saliva.. The ordinary galvanometer reading is 

 naturally the algebraic sum of the two opposing currents. 1 



1 Langley has adopted this view with the difference that he maintains 

 as the result of his experiments with atropine, that the explanation of the 



