RESEARCH FOR ARSENIC AND ANTIMONY. 
99 
mixture of nitrate and carbonate of soda. Antimoniate of 
soda was thus formed. This, when dissolved in water and 
acidulated with hydrochloric or tartaric acid, yielded, under 
a current of sulphuretted hydrogen gas, a deposit of sulphide 
of antimony, the colour of which, however, was liable to 
be obscured by an admixture with some sulphur. This mode 
of corroboration is not so delicate as that proposed by Mr. 
Watson. 
The process of Reinsch, therefore, is now rendered as satis¬ 
factory for the detection of antimony as of arsenic; and by 
comparison with the process of Marsh, it is not only more 
delicate, but far more convenient in its application. Marsh’s 
process may be used in the manner above described simply 
for corroboration. 
In comparing the two processes for the separation of 
antimony from liquids, I have found that Reinsch’s method 
is twenty times more delicate in revealing the presence of 
antimony than that of Marsh, as it is usually employed. 
Thus, a minim of water containing the 1-2000th part of 
a grain of tartarised antimony, mixed with ten minims of 
water and two of hydrochloric acid, gave a violet-coloured 
deposit of metallic antimony on boiling it in a piece of pure 
copper-foil corresponding to one twelfth of a square inch. 
A second piece of equal size introduced came out of the 
liquid untarnished; hence all the antimony had been depo¬ 
sited. Estimated by the degree of dilution, the propor¬ 
tion of antimony here separated was not more than the 
1-48,000 part of the liquid. These appear to be the limits 
of Reinsch’s process for antimony; and it will be seen that 
it is twice as delicate for arsenic, since the 1-4000th part of 
a grain of the latter metal admits of separation as a visible 
deposit. 
The introduction of Reinsch’s method gave great facility 
to the detection of arsenic in the tissues . The organ or solid 
containing arsenic was cut up and boiled in the requisite 
proportions of water and acid; it yielded a liquid which 
readily gave a deposit of metallic arsenic on copper. In 
some cases the acid liquid was strained or filtered off and 
tested ; in others, the copper v T as at once boiled with the 
organ cut into small pieces. In either case the long and 
troublesome carbonisation of the viscera was dispensed w ith; 
and the frothing in Marsh’s process, as well as the ambi¬ 
guous stains from a variety of substances, w r ere no longer 
obstacles to the analyst. This method has been very exten¬ 
sively employed in this country in judicial researches. 
It has been used by Dr. Christison, Dr. Douglas Maclagan, 
