560 POISONS : THEIR EFFECTS AND DETECTION. [§ 742. 
parts of lead mixed with 3 of arsenic ; the common Britannia metal used 
for teapots, spoons, etc., often contains arsenic ; and brass is bronzed 
with a thin film of arsenic. It was formerly much employed in the 
manufacture of glass, but is being gradually superseded. It is also now 
used to some extent in the reduction of indigo blue, and in that of nitro- 
benzole in the manufacture of aniline. 
In cases of suspected poisoning, therefore, and the finding of arsenic 
in the stomach or elsewhere, it may be set up as a defence that the 
arsenic was derived from shot used in the cleansing of bottles, from the 
bottles themselves, or from metal vessels, such as teapots, etc. 
The arsenic in all these alloys being extremely insoluble, any solution 
to a poisonous extent is in the highest degree improbable. It may, how¬ 
ever, be necessary to treat the vessels with the fluid or fluids which have 
been supposed to exert this prejudicial action, and test them for arsenic. 
The treatment should, of course, be of a severe and exhaustive character, 
and the fluids should be allowed to stand cold in the vessels for twenty- 
four hours ; then the effect of a gentle heat should be studied, and, 
lastly, that of boiling temperatures. The analysis of the alloy itself, or 
of the glass, it would seldom be of value to undertake, for the crushed 
and finely divided substance is in a condition very different from that of 
the article when entire, and inferences drawn from such analytical data 
would be fallacious. 
Arsenious anhydride is also used for the preservation of wood, and 
is thrown occasionally into the holds of vessels in large quantities to 
prevent vegetable decomposition. In India, again, a solution of arsenic 
is applied to the walls as a wash, in order to prevent the attacks of insects. 
§ 742. 1. Pharmaceutical, Non-official, and other Preparations of 
Arsenic.—Pharmaceutical Preparations. —The absence of organic medical 
preparations from the British Pharmacopoeia of 1914 shows how recent 
is the introduction of these powerful and widely used remedies. 
Arsenious Anhydride is official, also two solutions of the anhydride, 
viz. :— 
(a) Fowler’s solution , made up of 10 grms. of arsenious anhydride, 
10 grms. of potassium carbonate, coloured with 30 millilitres of com¬ 
pound tincture of lavender, and made up to 1000 millilitres with distilled 
water. Strength, 1 grm. of arsenious acid in 100 millilitres. 
(b) Hydrochloric solution of arsenic .—The same strength as the above ; 
it is simply a solution of arsenic in dilute hydrochloric acid, the latter 
being 12 volumes in 1000. 
Arsenious Iodide, Asl 3 , is official, and so is a solution of arsenious 
and mercuric iodides. Strength, 1 grm. of arsenious iodide and 1 of red 
mercuric iodide in 100 millilitres. 
Liquor Arsenii et Hydyrargyri Iodidi (Donovan’s solution of 
arsenic).—This is not official, but is used to some extent in skin 
