The mirror., 1922-05-25
ACCIDENTAL DISCOVERIES
Continued from page I


the stone. There were a few minutes of
Kissing and effervescing in every part ex-
cepting that covered by the ink, and when
this ceased, Senefelder noticed, with de-
light which may well be imagined, that
the stone had been eaten by the acid,
leaving the writing about one-twentieth of
an inch in relief. Alloys Senefelder in
purely accidental way~had re-discovered
the process suggested by Dufay some
seventy years before, of printing from
stone Qithography, literally, writing with
stone).
Senefelder had made a wonderful dis
covery, but he was without means to per-
feet it and put it to good purpose. So he
formed a partnership with musician
named Glaissman. A press was made, the
score of musical composition was drawn
on the lithographic stones, and in 1896
several pieces of music were printed from
these-the first lithographic prints ever
published. For his success in this line
Senefelder got one hundred forms from
the elector, Charles Theodore, and the
Academy of Sciences was moved to give
him twelve forms, saying that as he ad-
mitted his press had cost him six forms,
the directors deemed it generous to give
him double this amount.
Senefelder successively invented ink,
chalk-etching, trasfer, and wood-cut proc
esses and also the process of lithograph-
ing in colors. He was placed at the head
of royal lithographing establishment with
a salary of 1,500 forms year. In 1919
he published a full disclosure of all his
secrets. deeming himself amply repaid in
seeing, during his lifetime, his invention so
generally appreciated. Full of honors, and
with the manuscript of his last comedy
still imprinted, he died at Munich in
February, 1884.
1t was Dufay, member of the French
Academy, who in 1928, first suggested
printing from stone, but it seems to have
ended in suggesting until Senefelder's ac-
cidental discovery. Dufay's plan was to
make drawing on the proper sort of
stone with varnish and employ acid to cut
down the unprotected parts.
The art of TYPOGRAPHY depends upon
three things-the absorbent affinity of cal
careous stone (stone containing carbonate
of lime) to water; its adhesive affinity to
resinous and oily substances; and the
chemical affinity of those substances to one
another, combined with their repulsion of
water. The process of lithograph etching
and printing is simple and practically the
same today as when practiced by Alloys
Senefelder.
A drawing is made on polished stone
with resinous or oily crayon or specially
prepared ink, which adheres firmly to the
stone. Water poured upon the stone thus
prepared is absorbed by the uncovered
parts and repelled by the crayon or ink.
Thus acid etches out every part but the
drawing or writing. When the eating pro-
cess is done, colored oily or resinous sub
stances applied to the stone adhere to the
drawing and not to the moistened parts.
The stone is linked and moistened for each
impression and all the way from 500 to
more than 100000 prints may be taken
from single stone, according to the fine
ness or coarseness of the drawing.
The discovery of photography about the
beginning of the nineteenth century did
much to further and simplify the process
of TYPOGRAPHY. Repeated experiments
with sensitized plates developed that the
pictures on their surfaces could be trans
ferred successfully to lithographic stone
and thus do away with the necessity for
hand drawing. These transfers were then
treated in the ordinary way to prepare
them for printing.
Photolithography and photozincography