Washington telegraph., 1847-07-07
ANAsrATIC PRINTING.

ibu 'heoil nl anAslalic printing Is based
upon the well know properties Of the sub
stances employed in the process. For in.
stance, there is, as we are aware, an at.
traction in water for water. oil, as we
know, attracts oil, whereas these two sub.
stances repel each other. Metals are far
more readily moislcncd by oil than by
water, but more readily atil by weak
solution OF gum and with even yet greater
facility by waief in which phosphoric acid
Is dissolved. In addition TO these proper.
tics, thus possessed by water, oil, aud the
metals, the following ma, be looked upon
US the fundamental principle oil Anastatic
printing, namely, the facility with which
the ink Of newly printed book or englay.
Ing may be transferred by pressure to an.
other even surface.
The impression OF recent newspaper,
for instance, when laid upon u white sheet
Of paper, may be transferred 10 the latter
hy pressure, so that al! ls letters will be
distinctly reproduced lhereupon. This will
enable Us 10 comprehend readily the process
OF Anaslalic printing.
The printed paper, be it type or an en-
craving, Is first 10 be moi.teneI with diluted
nitric acid, aud then powerfully pressed by
mhans ul a faller on the surface Of an even
slae plate, by means Of which every part
o the sheet Is broagh, into immediate con
tact with the zinc. The acids with which
The white portions oi the paper are saturated
attack the metal, the printed portions
thereof being simultaneously transferred to
lls surface "a that the zine plate ai,cr this
process represents reversed copy Of the
printed Objects. The principles above al.
.ulrd TO are now brought u bear. Tae
zlnc plate thus prepared is 10 have poured
over il a solution ot gum In diluted phos.
Phofc acId. The iiuid is attracted by those
portions OF tue plato that The acid has pre-.
,ious.y attacked, aud moislens them with.
oul difficulty, whereas /; is frpelled by The
oil, contained in the Transferred portion Of
the printers Ink. The plate is now to
have an mixed roller passed over il, whereby
ibe very reverse action Is brought about.
The rcplslpn between the oil OF the iul,
ani the maisl surface of the plate over
which the roller is passed, prevents the
grease from adhering to those portions oil
is surface upon which there are no printed
lines or strokes, while from The attraction
Ui oil for oil, the ink is retained upon all
the printed paris, Tho Ana,ta,ic plate /.
thu, ready Tor use. and impressions may bo
lhIo"n oil from ii as ia The ordinary litho.
graphic process.
The method Of obtaining. by the Anas.
h'ic process, copies Of antique originals,
he lDk OF which is no longer transferable
by simple pressure, Is rs follows: The
printed paper is first to be laid in a solution
OF potash and subsequently in solution Of
a'iarlc acid. The consequence thereof Is
that all the blank portions OF the paper
become penetrated by minute crystals Of
iahralr oi potash, aud a. this salt rcpels
water, an mixed roller may then be passed
over the surface Of the paper without the
lnk adhering 10 any parts but where the
INK Ui the impression is. The taHrate is
then 10 he removed by careful washing, an |
the operation proceeded with as above de.
scfibcd, beginning by moislcning the paper
with dilute nitric acid.
I he impressions which it is desired 10
reproduce may be either from recent OF
liom Old originals, "a hundred years old
indeed or more;l their age is quite imma
terIdl; the copies produced being in every
case equally excellent, SO much so indeed,
that they are not to be distinguished from
the originals themselves,
by means Of this process old or faded
cngrdyIngs and eichngs may be so reno,
waited Us TO have all the appearance Of re.
cent impressions. One special merit in
the invention lies in the method resorlcd
10, and that with complete success, for pre-.
venting the extension OF the ink when ek.
posed 10 any pressure 10 which il may be
submitted, aud by which means the finest
lines and the sharpcsl outlines are repro.
duced with the creates, precision. When
ordinary type is transferred by this new
process 10 zinc plate, the impression,
which the latter affords has precisely the
appearance, as they leave the press, oI
being taken from metal types; and as in
this new method Of printing, the impressions
are not transferred to stone but to zinc.
which may be used with the ordinary
steam presses in the form Of cylinders we
have It in our power TO multiply To any
extent both text and illustrations in the
cheapest and in tho most rapid manner.
There is n single printer in London whose
stereotype plates are valued at f300, 900,
an outlay which this discovery renders
hcncelorwarl unnecessary What advan.
lagcs Tor printers, booksellers and the pub.
lic!-Poiyiechnie Magazine.