316 MATHEWS. 



injection consequently gave a greatly augmented secretion at 

 12:39. Thereafter each stimulation yielded less and less, and 

 finally at 12:59 only 3 mm. were secreted. The ducts may be 

 assumed to be practically empty. Quinine solution was now 

 again injected, and the next sympathetic stimulation yielded 

 again a greatly augmented secretion. Finally at i : 1 1 the sym- 

 pathetic failed to yield any secretion, and from then until 

 4 p. :m. was totally ineffective. It w^ould be said, at first sight, 

 that the nerv^e was paralyzed. Such, however, was not the 

 case, its seeming paralysis being due to the emptiness of the 

 gland. This was shown by the injection of .5 % NaCl solution 

 into the duct. The following stimulation of the sympathetic at 

 4:02 yielded a very large secretion. 



This experiment in two ways furnishes very strong evidence 

 of the muscular nature of the sympathetic secretion. The fact 

 that sympathetic secretion may be obtained long after paralysis 

 of the chorda is very suggestive. Heidenhain* maintains that 

 the chorda secretion is paralyzed by the action of the drug on 

 the gland cells. If this be true, and I see no reason to doubt 

 it, it furnishes very strong evidence that the sympathetic pro- 

 duces its secretion in some other manner than action on the gland 

 cell, for the sympathetic secretion is not materially affected long 

 after the gland cells have been completely paralyzed. The fact 

 that the nerve's effect soon passes away, but may be restored 

 by the simple injection of more quinine solution or other fluid 

 into the duct, I believe to be susceptible of but one explanation, 

 /'. e., that the nerve causes this secretion by compression of the 

 ducts and alveoli. 



A similar phenomenon is witnessed if the gland artery be 

 compressed and fluid thus cut off from the gland. A few stimu- 

 lations of the sympathetic sufifice to render the nerve inoperative, 

 but by injection of fluid into the duct the nerve is shown to be 

 still active. 



* Heidenhain, Studien aus Breslau, IV, 1868, p. 85, "so wird die Erregbarkeit 

 der absondernden Elemente bald herabgesetzt und nach kurzer Zeit ganz vernichtet. ' ' 



