The Washington union. [volume] (City of Washington [D.C.]) 1857-1859, 1858-11-19
THE SUN AN ENGRA YER ON WOOD, STONE,
COPPER, AND STEEL.
From the New York Evening Post.

No science within the last few years has made rapid
progress the science of photography and brilliant
have been its former maryes they surpassed by more
striking achieved almost within the month Sun
pictures on silver and paper have been made almost
common newspapers in every household, even the
poorest portraits which otherwise would have been
beyond their means, and which hundred years ago
gal opuence could hardly This was great ad
dton to the happiness of the world for any art to con-
tribute But its devotees still asked for and more
they succeeded In obtaining Pctzva pressed the most
subtle mathematical analyses into the service of the art
to make its pictures accurate in drawing, and more
rapid in execution. NJ Niepce then showed how the
could be made to do the work of the photographer
He photographic stone with solution OF btu
men in ether this he places any Photographic pic
turc on glass paper engraving This is subject
cd to the action of the light. The stone is then placed
in bath of ether, the portions which the light has
acted being soluble and the other portions nsoluble The
stone is removed from the BATH and delicate picture is
found skeched it by the nsoluble portions Of btu-
men, from which Autographs may be directly printed.
Our columns have related from time to time the vari
GUS improvements OF this snpcturng art cspec ally in
its relation to astronomy where improvements have been
remarkable as in any other of its numerous branches
Our advertising columns have shown that photography
successfully applied not only to hogaphy but also
to wood engraving, and that with the greatest success
All these impressions. however, of little durability
and permanence, compared with those copper From
the London News learn that Herr Presch has sought
to make the copperplate engraycr and has sue
cecded He finds property of matter strange as
that possessed by btumen. He glass case with
solution of gclaine mixed with solution OF bichro-
mate Of potash and other clomcals and leaves il TO dry
in the dark On this plate he places his glass paper
picture which he wishes to engyc, and exposes 1t to the
light faint Photographic picture appears on the pre-
pared geatinous surface. This is dipped in water The
moisture raises the picture in relief 1t is dried, and
found to be strong enough and deep enough TO afford an
impression, by pressure, to sheet Of guta percha
This guta percha impression has but to be covered with
black lead bronze POWDER and placed in votaic cir
cult to be covered with copper by tho eectrotype pro-
cessitscf wonder of wonders. The copper plate thus
produced in relief but being placed in the matrx in
the gavanic bath, tproduces many engraved copper
plates as the engrayer may require
Fox Talbot, the father of the English photography,
goes step beyond this. He places Herr Pressch sou
luton of gcatne and bichromate of potash directly
plate of polished steel The picture is impressed on
this film before He discovers that there is no necess
ty to peril its faintest lines by immersion In the water
bath Over the faint photograph on the gelatinous film
he Sits thin layer of powdered gum copal, or even
rosin The plate is then heated over spirit lamp to
melt the gum in the common etching process. So
luton of the paroxde of iron in muratc ncd poured
the plate which etces out its surface wherever the
light has acted the geatne. And thus light leaves
its delicate footprints on mperishable steel
The engraver of the highest orier who is artist
well manpulator may still produce the best efforts
of his art but instead of having for his audience only
the favored few he may be admired by the million MS
we'll The cartoons of the great masters, which fill
choice inches in the royal galleries and grand cahedrs
the satuay which the pilgrims Of the world go far
to the masterpieces in plastic aud pictorial art with
all the wonders of nature and science visible to the mi
crcscopst the astronomer may thus at distant day
oomc to adorn the cottages of the poor.