ON THE DETECTION OP ARSENIC. 
279 
of tartaric acid in one of the salt. It follows, as a consequence, 
that the remainder unaccounted for, after estimating the wa- 
ter, oxide of iron, and tartaric acid, is ammonia; so that the 
following statement of the whole result will give the relation 
between theory and experiment, in 30 grains of the salt. 
Experiment. Theory. 
Sesqui-oxide of iron 8.70 8.82 == 80. 1 equiv. 
Ammonia 1.93 1.86 = 17. 1 «' 
Tartaric acid 14.66 14.61 = 133. 2 " 
Water 4.71 4.71 = 43. 4 «-f 
30.00 30.00 
Formula (Fe 2 3 +T)-f (PPN-f T)+4HO-f- 
ART. LVIII. — MEMOIR UPON THE DETECTION OF ARSENIC 
FORMING A TOXICOLOGICAL COMPENDIUM, AS FAR AS 
REGARDS THIS SUBSTANCE. By Augustine Duhamel. 
Chapter of Contents. 
Preliminary observations — Arsenical preparations employed as poisons — 
Character of arsenious acid— Distinctive characters presenting means 
of its recognition—Reduction — Manner of proceeding when this sub- 
stance is made the subject of medico-legal inquiry^-Marsh's apparatus, 
with the modifications and improvements upon it— Figuier's process for 
separating the organic matters, and isolating the arsenic by an improved 
and infallible method— Absorption of arsenic by the animal tissues, and 
its detection after long inhumation— Symptoms which betray the poi- 
sonous action of arsenic upon the living economy— Antidote. 
The lamentably frequent instances of human destruction 
by this energetic poison, both in this and other countries, ren- 
der it obvious to every reflecting mind, that any means which 
may be used to bring the subject fully under the notice of 
apothecaries and physicians, should command the deepest at- 
