ARSENICAL POISONING FROM SMELTER SMOKE IN 
THE DEER LODGE VALLEY, MONTANA. 
By D. E. Salmon, D.V.M., Montevideo, Uruguay, S. A. 
(Continued from May issue.) 
4. Are similar lesions produced by the artificial application 
of arsenic to the horse's nostril? —Similar, and, according to the 
writer, identical, lesions were produced experimentally in horses 
which were stabled and protected from the influences which 
caused the ordinary ulcers. However, it must not be supposed 
that a mere dab of arsenic on the mucous membrane of a horse's 
nose will cause the formation of an ulcer; for the process is 
neither so rapid nor so simple as to be developed in that manner. 
It has seemed to the writer that the local irritating and cor¬ 
roding effect of arsenic when applied to the intact skin or mucous 
membrane is much less active than is generally believed. For 
example, Peterson and Haines say 1(4) 
“ In the vast majority of cases the local action of arsenic is 
pronounced. . It does not corrode dead and living tissue alike, 
as would the corrosive acids and alkalies. Vital irritability is 
required, or the effect on organic matter will be relatively small. 
Applied to a part, it irritates so profoundly that the phenomena 
of inflammation appear at once and make rapid progress to the 
latest stage of local death. It blisters the skin like a burn, and 
the mucous surfaces respond with equal promptness to its cor¬ 
roding touch.” 
Now, while arsenic will do all of this, there is an element of 
time required which might not be suspected from reading this 
paragraph; and this is precisely because arsenic is not a corrosive 
poison like the alkalies and mineral acids. That is, it must enter 
the cells and exert its action on the living protoplasm, and this 
action is made apparent, if the quantity of arsenic absorbed is 
300 
