1865.] fur certain Organic Poisons. 273 



by one half. More frequently the irregularity consists in one or more 

 portions of the ventricle (especially the apex) becoming rigidly white and 

 contracted, while the remainder of the organ continues to dilate regularly. 

 When these yielding pulsations are small, a peculiar appearance, as if the 

 wall of the ventricle formed crimson pouches or protrusions, is produced. 



4. No other substance, except those mentioned above, has been found 

 to produce this chain of effects, even in a single experiment. We have 

 ourselves tried nineteen different substances, consisting of vegetable extracts 

 and alkaloids. Of these, emetina, and the extract of the Delphinium 

 staphisagria caused somewhat similar irregularity of the cardiac beats ; but 

 in frogs, poisoned by these agents, the muscular power was always lost 

 before the heart had ceased to beat, and the ventricle stopped in the 

 dilated, and not in the contracted, state. 



5. When digitaline is applied endermically to frogs, the characteristic 

 effect is invariably produced, if a sufficient quantity be used. This quan- 

 tity no doubt varies with the size of the animal, but may be stated gene- 

 rally at Yijoth of a grain. Quantities less than yl^th grain usually produce 

 no effect, or at most only temporary irregularity of the heart's action, of 

 a more or less characteristic kind. The result of the injection of doses 

 larger than T ^th grain is to diminish the interval between the administra- 

 tion of the poison and the stoppage of the ventricular beats. This interval 

 appears to be seldom less than six or seven minutes, however large the 

 quantity of digitaline. 



6. Very poisonous effects are produced in frogs by the endermic ap- 

 plication of alcoholic or acetic extracts of matters vomited by patients, or 

 taken from the human stomach after death. The extracts are less poison- 

 ous, if at all, to the higher animals. 



7. The symptoms produced by these extracts in frogs are in marked 

 contrast to those caused by the cardiac poisons. Like these agents, the 

 animal extracts impair the action of the heart ; but their tendency is to cause 

 paralysis of its muscle, and stoppage in the dilated condition. At the 

 same time, they generally destroy the muscular power of the animal. 



8. The cause of the toxic action of these animal extracts has not been 

 ascertained ; it is probably not always the same, as the effects produced by 

 different extracts are not perfectly similar. These effects are perhaps the 

 result of the combined action of different substances. They are certainly 

 not caused by bile or pepsine, and probably not by any substance in a state 

 of decay. 



9. The vegetable acids, when injected in sufficient quantity, stop the 

 action *of the heart more rapidly than any poison with which we are ac- 

 quainted, the organ remaining distended with blood when it has ceased 

 to beat. The toxic action of the "animal extracts is not, however, caused 

 by these acids ; for the quantity of them contained in the extracts is too 

 small, and the effect is not diminished by neutralization with an alkali. 



10. When digitaline, in quantities of \-\-\ grain, is added to vomited 



