Loudon free press. (Loudon, Tenn.) 1852-1855, 1854-09-06
New Kind of Printing.

The following from the "London Journal of
The Society of Arts" describes new discovery
oy Felix Abate, of Naples, for representing Ger
tain objects by printing direct from them.
From the description of the process, it will be
remarked; perhaps with some degree ofsurprise
the excessive sepstiveness of vegetable SUBJ
stances under the joint action of acids and heat
so that an infnitessimal dose Of the former, and
an instantaneous application of the latter, are
sufficient to produce the most striking effect.
/ The process is as follows:-
Suppose sheet of veneering wood be the
object from which impressions are to be taken:
/ expose the wood for few minutes to the cold
evaporation Of hydrochloric or sulphuric acid,
or slightly wet it with either of these ACIDS di-
/ luted. and then wipe the acid well off from the
surface. Afterwards it is laid upon piece of
calico or paper, or common wood, and by a
stroke of The press an impression is taken, which
! is, Of course, quite invisible; but by exposing
/ this impression, Immediately AFTER to the action
/ of strong heat most perfect and beautiful
representation of the printing wood instantane-
ously appears. In the same way, with the same
plate Of wood, without any other acid prepara
ton, number of impressions, about twenty or
more, are taken; then as the acid begins to be
exhausted and the impressions faint, the acidif
cation ofthe plate must be repeated as above,
and 50 on progressively. as The wood is not in
the least injured by the working of the process
for any number of impressions. All these i'm
pressions show general wool-Hke tint, most
natural for the light-colored woods, such as
oak, walnut, maple, &C.; but for other woods
that have peculiar color, such as mahogany,
rosewood, &C.. the impression must be taken, if
true imitation be required. on a stuff dyed of
the light color of the wood.
Il must be here remarked, that the impreS.
sions, as above made, show an inversion oftints
in reference to the original wood, 50 that the
light are dark, and vice versa, which, however,
does not interfere with the effect. The reason
of it is, that all the varieties of tnts which APP
pear in the same wood are the effect of the vary
ing closeness of its fbers in its different parts,
SO that where the fbers are close, the color is
dark, and light where they are loose; but in the
above process, as the absorption of the acid is
greater in proportion to the looseneSs of its
fbers; the effect must necessarily be the reverse
of the above. However, when | wish to pro-
duce the true effect of the printing wood, alter
the process as follows: wet the surface upon
which the impression is to be taken with dilute
acid, and then print with the yeneeering wood
previously wetted with diluted liquid ammonia
it is evident that in this case the alkal neutral
izing the acid, the effect resulting from The sub
sequent action Of heat will be true represen
tation Of the printing surface.
Such is thermography or the art of printing
by means of heat. Now it is nothing but nat
ural to anticipate in regard to this art, as well
as TO the other above described processes for
printing directly from Objects that they will
afford most important services to the natural,
botanical mineralogica and anatomical scien-
ces; as it is by their. means that the internal
structure of bodies is unveiled TO the eyes of the
philosopher, and the wonders ofnature, in their
inexausthe variety are indefinitely multiplied,
to be subjected to the investigation and to serve
the gratiteation of mankind.
But the new art will prove not less useful to
the decorative arts, particularlyin in its applica-
ton to produce limitations of rare and costly
woods, as veil as of works of art, mosaic aud
inlaid work, applicable for paper hangings, or
for furniture, in TIE place of veneering, these
limitations being produced at an exceedingly
low cost, while they rival in perfection the origi
nal objects, enabling those whose means are
limited to obtain decorations at once cheap and
in good sie.-[Scientifc American.