80 
MISCELLANY. 
of aqua regia was recommended ; but, besides that this powerful agent 
will hardly ever generally be employed by the female sex for the removal 
of names and figures from fine cambric, lawn, and linen handkerchiefs, 
a doubt as to its efficacy can hardly be suppressed ; but not having had 
an opportunity of putting this method to the test, I abstain from giving 
any contrary decision, and at once proceed to communicate a means pro- 
ducing the effect with certainty, at the same time in no way injuring the 
materials, which will be interesting to many and principally to chemists. 
The substance to be employed consists simply of a somewhat con- 
centrated solution of the cyanide of potassium of Liebig. 
Here I may be allowed to remark that the pure cyanide of potassium 
employed to form this salt must be free from sulphate of potassa, in 
order wholly to prevent the formation of a combination with sulphur 
during the calcination, which might interfere with the object in view. 
The said precaution in forming the cyanide of potassium should never 
be lost sight of by those who make gold or silver solutions. 
Writings made with chemical marking-ink on white bodies, table 
linen, towels, &c, of some years' standing, were in a very short time 
removed by gently rubbing the materials with a somewhat concentrated 
solution of cyanide of potassium, no injury whatever being perceptible 
even in the finest fabric. If a little common writing-ink enter into the 
composition of marking-ink (which sometimes is done with the inten- 
tion of improving the freshly made figures,) then, in addition to that, 
the spot or figure to be removed must afterwards be treated with a hot 
concentrated solution of oxalic acid. 
The black and reddish spots produced on the skin by solutions of 
gold and silver, are also in the same manner easily removed by the be- 
fore mentioned saline solution. — Ibid, from Ann. der Chem. und Pharm. 
