MEDICO-LEGAL CONTRIBUTIONS ON ARSENIC. 
169 
duct, the animal is almost instantaneously poisoned, if the 
gland is in a state of rest; but if the secreting powers have 
been previously called into play, the animal resists for a 
pretty long space of time. 
In order to convince you of the rapidity with which 
absorption takes place in the glands, we shall now inject into 
the parotid duct of the horse which has already served for 
our previous experiment a solution containing 1-100th 
part of iodide of potassium; the duct being then tied 
over the canula, we shall almost immediatelv discover iodine 
in the secretion of the parotid on the opposite side—a fact 
which proves that, after passing through the vast extent of 
the entire circulatory system, the substance injected has been 
eliminated again by the glands, in an incredibly short space 
of time. 
(The experiment is tried on the horse, and succeeds per- 
fectl 3 \ The reactions of iodine are not, however, distinctly 
perceived before a few seconds have elapsed after the injec¬ 
tion.) 
You see, gentlemen, that, although rapid, the elimination 
has not been altogether instantaneous; but in the horse the 
circulation is known to be particularly slow; by injecting 
prussiate of potash into the jugular vein, and testing the 
blood drawn from another point, Hering has proved that in 
this animal the blood does not accomplish its entire circuit in 
less than twenty-five seconds — a fact which sufficiently 
accounts for the comparative slowness of the process of 
elimination. In the dog the same result would be more 
rapidly attained .—Medical Times and Gazette, 
MEDICO-LEGAL CONTRIBUTIONS ON ARSENIC. 
By Charles H. Porter, M.D.,* Professor of Chemistry 
and Medical Jurisprudence, Albany Medical College. 
Intending in this paper to report a number of cases of 
arsenical poisoning, it has ,been deemed advisable to preface 
them by an account of the methods pursued for the detection 
of the poison. This is done for the reason that, when the 
details are given, each one may judge for himself as to the 
degree of reliance to be placed upon the results, and also 
because medical men generally are not acquainted with the 
minutiae of such examinations. 
* Communicated by the author, having been presented to the Aledical 
Society of the State of New York. 
