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on the Action of Poisons on the Animal System. 
was found that by means of the Voltaic battery powerful con- 
tractions might be excited, not only of the voluntary muscles, 
but also of the heart and intestines ; from which it may be 
inferred, that the muriate of barytes, like arsenic, affects the 
circulation by rendering the heart insensible to the stimulus 
of the blood, and not by destroying altogether the power of 
muscular contraction. 
The muriate of barytes affects the stomach, but in a less 
degree than arsenic. It operates as an emetic in animals that 
are capable of vomiting ; 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 same circulation, leads to the same conclusion 
with regard to the muriate of barytes. 
V. On the Effects of the Emetic Tartar. 
The effects of the emetic tartar so much resemble those of 
arsenic and 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. 
When applied to a wound in animals, which are capable of 
vomiting, it usually, but not constantly, operates very speedily 
