570 poisons: their effects and detection. [§§ 749 , 750 . 
is then slightly augmented until relatively large doses are taken with 
impunity. In one case 1 it appears that a countryman, in good health, 
and sixty years of age, took daily 4 grains of arsenious acid, a habit 
which he had inherited from his father, and which he in turn bequeathed 
to his son. 
The existence of such a custom as arsenic-eating, in its literal sense, 
has more than once been doubted ; but all who have travelled over Styria 
and other places where the habit prevails have convinced themselves 
that the facts have not been overstated. For example, Dr Maclagan, in 
company with Dr J. T. Rutter, 2 visited Styria in 1865, and, having 
carefully weighed 5 or 6 grains of arsenic, saw these doses actually 
swallowed by two men. On collecting their urine, about two hours 
afterwards, abundant quantitative evidence of its presence was found ; 
but in neither of the men were there the slightest symptoms of poisoning. 
It is obvious that the existence of such a habit might seriously complicate 
any inquiry into arsenical poisoning in these regions. 
§ 749. Manner of Introduction of Arsenic. —Arsenious acid exerts a 
poisonous action, whether it is taken by the stomach, or introduced into 
the system by any other channel whatever. The differences in the 
symptoms produced by external application (as through a wound), and by 
swallowing arsenious acid in substance or in solution, are not so marked 
as might be expected. It was probably Hunter who first distinctly 
recognised the fact that arsenic, even when introduced outwardly by 
application to an abraded surface, exerts a specific effect on the mucous 
membrane of the stomach. Brodie 3 states : “ Mr Home informed me 
that in an experiment made by Mr Hunter himself, in which arsenic 
was applied to a wound in a dog, the animal died in twenty-four hours, 
and the stomach was found to be considerably inflamed. I repeated 
this experiment several times, taking the precaution of always 
applying a bandage to prevent the animal licking the wound. The 
result was that the inflammation of the stomach was commonly 
more violent and more immediate than when the poison was 
administered internally, and that it preceded in appearance the inflam¬ 
mation of the wound.” 
§ 750. Cases of Poisoning by the External Application of Arsenic. 
—A mass-poisoning by the external use of arsenical violet powder to 
infants occurred in England some years ago. Two deaths from this 
cause were established by coroners’ inquests. 4 Dr Tidy found 
the violet powders used in the two cases to have the following 
composition :— 
1 Tardieu, op. cit. 
2 Edin. Med. Journ., April 1865; Brit, and For. Med. Chir. Journ ., Oct. 1865. 
3 Phil. Trans., 1812. 
4 “ Gleanings in Toxology,” by C. Meymott Tidy, M.B., Lancet, Aug. 21, 1878. 
