76 
SULPHURET OF ARSENICUM AS A DEPILATORY. 
ties of each of the compounds which might exist or be produced in 
the mixture of sulphuret of arsenic, lime and water, which was ap- 
plied to sheep-skins for the purpose of removing the wool ; and I 
then discovered that neither the lime, nor the arsenious acid, nor 
the sulphuret of arsenic had any notable influence on the result, but 
that this depended on the action of nascent sulphuret of calcium 
formed by the reaction of lime on the sulphuret of arsenic. 
I proved, indeed, that sulphuret of calcium acts powerfully as a 
depilatory when employed alone, and that it partakes of this pro- 
perty in common with the monosulphurets of sodium, of barium, and 
of strontium. 
These observations naturally suggested the substitution of sul- 
phuret of sodium, or hydrosulphate of soda for the sulphuret of ar- 
senic, the former having been already introduced as as a therapeu- 
tical agent, and especially in the fabrication of mineral waters and 
sulphur baths. This new agent succeeded beyond my hopes, and 
gave more rapid results than the orpin itself ; so much so that only 
a few hours after its application to a sheep-skin I could without ef- 
fort detach the wool in a single piece. 
Nothing, could, therefore, be easier than to substitute sulphuret of 
sodium for sulphuret of arsenic in depilatory processes. The ex- 
pense of the process would not be thereby increased, and both with 
reference to the health of the workmen engaged in making, pow- 
dering and applying the orpin, and the security of the public who 
are interested in restricting the use of substances which might be 
productive of poisonous effects, such a substitute would be very de- 
sirable. 
Encouraged by this first success my attention was directed to the 
depilatory powders and pastes, which are extensively used in the 
East, and not unfrequently in France, for removing superfluous 
hairs. 
The Turkish rusma, and the depilatories of Plenck, of Colley, 
and of Delcroix, may all be described as mixtures in different pro- 
portions of lime and sulphuret of arsenic, to which some add gum, 
and others starch, and sometimes a little caustic alkali; and these 
preparations are applied to the skin after being made into a paste 
with a little water. 
These means do not always answer the intended 'purpose well, 
and their adoption is subject to serious evils. 
