* " * ‘ » bes 
Electrography. * ; 161 
* 
> 
obtained, have all the sharpness of the original, and may be bronz- — 
ed in the usual way, to any color which may suit the taste of 
the experimenter.* 
Engraved plates of copper may be copied with equal success 
by this method, and already this has become an important branch | 
of the engraver’s art,+ and we hear of large and elaborate plates 
being thus multiplied to any desired extent. We should suppose 
that by availing ourselves of this advantage, the great expense 
of steel plates might be avoided. Such copies may be fur- 
nished at a price but little exceeding that of ordinary engraver’s 
copper. Mr. Spencer says, that copies of engraved plates may 
be taken in lead, by pressure as before described, but we should 
doubt if large plates could be thus treated with success ; and that 
the first copy ought to be in copper, which when once obtained 
will answer any number of times. 
But the usefulness of this process would be much abridged 
Were it applicable only to metallic bodies. Such however is not 
the case. Almost any non-conducting surface may be rendered 
4 conductor by the following ingenious process, proposed by Mr. 
neer. Wash the surface to be metallized with nitrate of silver, 
by a camel’s hair pencil, a en expose this surface thus treated 
to the vapors of phosphorus dissolved in alcohol or spirits of tur- 
Pentine, which for this purpose should be placed in a capsule, 
and gently warmed by a spirit lamp, or over a sand-bath. In- 
stantly the silver is reduced to a phosphuret, and covers the whole 
t Beautiful examples of engravings thus obtained, appeared in the Westminster 
Review, for Septemper last, and side by side with them, impressions from the orig- 
inal pl. Gatien lh ae a t inati Dr. Chil- 
ton, of New York, has also obtained equally good results, an example of which | 
Was given in the J uly number of Prof. Mapes’ American Repertory. We ma p ale 
add, that we have succeeded in copying a plate, (a head of John Bunyan,) six by 
nine inches, and that in some future number, we may give some examples, as occa- 
ie may require. The London and Edinburgh Philosophical Magazine and New- 
‘on’s Journal, have also contained examples of this art. 
ol. xz, No. 1.—Oct.-Dec. 1840. 21 
