ACTION OF TOISONS ON THE ANIMAL SYSTEM. 



heart fnsensi- circulation by rendering the heart insensible to the stimulus of 



hie to the sti the blood, and not by destroying altogether the power of mus- 

 mulusol' the . . 



b j ooti cular contraction. 



The muriate of barytes affects the stomach, but in a less 



It affects the 



stomach, hot degree than arsenic. It operates as an emetic in animals that 



less thaa awe- are capable of vomiting j but sooner when taken internally, 



than when applied to a wound. In general,, but not constantly, 



there are marks of inflammation of the inner membrane of 



the stomach, but not of the intestine. In many instances there 



is a thin layer of dark coloured coagulum of blood lining the 



whole inner surface of the stomach, and adhering very closely 



to it, so as to have a good deal of the appearance of a slough ; 



and this is independent of vomiting, as, where I met with it, 



it occurred in rabbits. 



The same circumstances, from which it may be inferred, 



that arsenic does not produce its deleterious effects until it has 



passed into the circulation, leads to the same conclusion with 



regard to the muriate of barytes. 



V. On the Effects of the Emetic Tartar. 



Trneuc tamr The effects of the emetic tartar so much resemble those of 

 kas similar et- arsenic aod« of muriate of barytes in essential circumstances, 

 that it would be needless to enter into a detail of the individual 

 experiments made with this poison. 

 Applied to a When applied to a wound in animals, which are capable of 

 wwuiid. vomiting, it usually, but not constantly, operates very speedily 



as an emetic j otherwise I have found no material difference in 

 the symptoms produced in the different species of animals, 

 which I have been in the habit of employing as the subjects 

 of experiment. The symptoms are paralysis, drowsiness, and 

 at last complete insensibility ; the pulse becomes feeble j the 

 heart continues to act after apparent death ; its action may be 

 maintained by means of artificial respiration, but never for a 

 longer period than a few minutes : so that it appears, that this 

 poison acts on the heart as well as on the brain ; but that its 

 principal action is on the latter. Both the voluntary and in- 

 voluntary muscles may be made to contract after death, by 

 means of Voltaic electricity. The stomach sometimes bears 

 the marks of inflammation ; but at other times it has its natu- 

 ral appearance. I have never seen any appearance of inflam- 

 mation. 



