DIURESIS — PUPIL — LACRYMAL GLAND. 519 



Remarks, 



The results of this experiment, as regards the vascular 

 phenomena of blood-pressure, pulse, &c., have been already 

 fully noticed. 



The action of the drug on the secretion of urine is seen to be 

 very marked and characteristic, and the dependence of the 

 secretion on the blood-pressure is well shown in the accompany- 

 ing chart. 



Thus the average rate of urine secreted before administration 

 of casca being 5 minims in 10 minutes, an increase of 50 mm. in 

 the blood-pressure caused by the drug brought the rate of 

 secretion of urine up to 25 minims. When the action of the 

 drug was further pushed there was first decrease and then total 

 suppression of urine, the blood-pressure at the time of suppres- 

 sion being 200 mm. of mercury. 



Subsequently as the blood-pressure fell the secretion of urine 

 recommenced. 



The physiological explanation of these successive phenomena 

 appears to be that the primary increase of blood-pressure pro- 

 duces arterial fluxion to the kidney ; but that if the action of 

 the drug is pushed, the renal vessels become contracted so as to 

 prevent the blood reaching the kidneys, notwithstanding the 

 high pressure in the arterial system. It is worth notice that 

 the urine collected after the secretion had recommenced did not 

 contain albumen. 



In this respect the result of this experiment differs from those 

 obtained by Mr. Power and one of us in our experiments on the 

 action of digitalis ; it coincides, however, with those experi- 

 ments in its general results. {Cf. antea, pp. 410 and 412.) 



Action ox the Pupil and Lachymal Gland. 



In order to see if the drug exerted any local action on either 

 of these organs, we (Experiment XLV) placed some drops of 

 strong watery solution of casca in the eye of a cat, but with 

 purely negative results. 



