POISONS : THEIR EFFECTS AND DETECTION. 
[§ 742 . 
3. Rat and Fly Poisons, etc. —An arsenical paste sold for rats lias 
the following composition : — 
Arsenious acid . 
Lampblack 
Wheat flour 
Suet ..... 
Oil of aniseed, a small quantity 
50 
•6 
46-3 
46-3 
per cen*. 
99 
99 
Another rat poison is composed as follows :— 
White arsenic.46-8 per cent. 
Carbonate of baryta ..... 46-8 „ 
Rose-pink 1 .5-8 „ 
Oil of aniseed . . . . . -2 ,, 
Oil of rhodium.-2 
Various arsenical preparations are used to kill flies; the active 
principle of the brown “ pajpier moure ” is arsenious acid. A dark grey 
powder, which used to be sold under the name of fly-powder, consisted 
of metallic arsenic that had been exposed some time to the air. 
Fly-water is a strong solution of arsenious acid of uncertain strength, 
sweetened with sugar, treacle, or honey. Another fly-poison consists of 
a mixture of arsenious acid, tersulphide of arsenic, treacle, and honey. 
4. Quack and other Nostrums.— -The analyst may meet with 
several quack preparations for external use in cancer. A celebrated 
arsenical paste for this purpose is composed of :— 
Arsenious acid.8 per cent. 
Cinnabar. 70 ,, 
Dragon’s blood.22 „ 
Freres Come’s Cancer Paste is composed of arsenious acid, 1 ; 
charcoal, 1 ; red mercury sulphide, 4 ; water, q.s. 
The tasteless “ ague drops ” formerly used in malarious districts are 
simply a solution of arsenite of potash. 
Davidson’s Cancer Remedy consists, according to Dr Paris, of equal 
parts of arsenious acid and powdered hemlock. 
In India, arsenic given as a medicine by native practitioners, or 
administered as a poison, may be found coloured and impure, from 
having been mixed either with cow’s urine or with the juice of leaves, etc. 2 
Arsenious acid is used by dentists to destroy the nervous pulp of 
decayed and painful teeth, about the twenty-fifth of a grain (2-5 mgrms.) 
being placed in the cavity. A common formula is : Arsenious acid, 2 ; 
sulphate of morphine, 1 ; creasote, q.s. to make a stiff paste. There is 
no record of any accident having resulted from this practice hitherto ; 
but since the dentist seldom weighs the arsenic, it is not altogether free 
from danger. 
5. Pigments, etc. — King’s yellow should be As 2 S 3 , the trisulphide of 
arsenic or orpiment. It is frequently adulterated with 80 to 90 per cent. 
1 Alum and carbonate of lead coloured with Brazil and peach woods. 
* Chever, Med. Jurisprudence for India, p. 116. 
