60 
REPORT ON GILDING, ETC. 
ART. XV — REPORT MADE TO THE ACADEMY OF SCI- 
ENCES, PARIS, ON THE NEW PROCESSES INTRODUCED 
INTO THE ART OF GILDING BY MR. ELK1NTON AND 
M. DE RUOLZ.* By M. Dumas. 
The importance of this report and of the numerous appli- 
cations mentioned in it, induces us to give our readers such 
an extract as may enable them to obtain the principal re- 
sults mentioned. 
1. Gilding of Brass and Silver by the Mercurial Process 
at present in use. 
After having carefully scoured the piece, an amalgam of 
gold is applied to it, then it is burned. The mercury in 
evaporating leaves the gold on the surface of the object to 
be gilded ; but, in this process, the workmen being inces- 
santly exposed to the contact of liquid mercury or of the 
vapor of mercury, experience in the highest degree the fa- 
tal effects of poisoning by mercurial emanations. 
2. Gilding by the Humid Way. 
This process of gilding, which is very simple in practice, 
consists in dissolving gold in nitro-muriatic acid, which 
converts it into perchloride ; in mixing the latter with a 
great excess of bicarbonate of potass, and boiling the whole 
for a very long time. Pieces of brass, bronze or copper, 
previously well scoured, are steeped in the boiling liquor, 
and the gilding is immediately applied, a portion of the 
copper of the piece being dissolved to replace the gold 
which is precipitated. 
Mr. Wright, in a note addressed to the Academy, gives 
the following explanation of this process: according to him, 
* Abridged from the Comptes Rendus de VAcademit des Sciences. 
