■ 494 ON THE PHYSIOLOGICAL ACTION OF CASCA BARK. 



found on microscopic examination that the movements of the 

 cilia ceased in about the same time in both specimens. 



luffed 071 Processes of Oxidation. 



It, however, does appear to exercise an inhibitory action on 

 oxidation processes generally. This point was investigated in 

 the foUow^ing manner : — 



Experiment XYIIL— April 20. 



Four thin slices of potato were placed in two saucers, and 

 w^ere just covered, the one with distilled water, the other with 

 a -=j-J-(5- watery solution of casca. When a drop or two of the 

 tincture of guaiacum were added, either to the liquid or to the 

 potato slices, the bluing produced was much fainter in the case 

 of the saucer containing the casca than in that containing dis- 

 tilled water. The results of the experiment on organized and 

 unorganized ferments were negative, neither the development of 

 the yeast-plant (Experiment XIX) nor the digestion of fibrin 

 by pepsin (Experiment XX) appearing to be in the least degree 

 hindered by the addition of the drug. 



Action on the Digestive System. 



One of the most prominent symptoms of poisoning by casca 

 is the violent vomiting which it produces ; and, as has already 

 been noticed, its occasional purgative action is used as a test 

 of innocence or gnilt. The emetic or purgative action is sup- 

 posed by some to depend on the administration of a pure inlu- 

 sion, or of one containing the drugs in suspension, and innocence 

 and guilt are thus supposed to be practically decided by the 

 priests, who have it in their power to administer either one or 

 other to the accused. 



In order to test this, an infusion was given to one cat, B 

 (Experiment XXI), and an infusion containing a quantity of 

 powder to another. The latter, however, contrary to expecta- 

 tion, recovered, whereas the former died. The experiment, 

 however, was vitiated by the fact that the infusion was made 

 from the finely pulverized bark, the only kind we had at our 



