, 1896-02-29

A company Of ladies' and gentlemen. in
Guiding many exports In artistic matters.
spent a delightful hOur in the Fine Art
Society's Rooms in New Bond-Street yester-
day afternoon, in listening to a description by
Professor Hubert Hcrkomer. Of the new
black. and wlitca art OF which he Is the inyeu-
tor, and in witnessing a demonstration Of its
results and capabilities. Professor Herkomer
explained at the outset that Ivy this new art
the painter had it III his power to do black
and-White work. djff1sible by the printing
press, without departing ftom his accustomed
methods, for he was provided with paint to
manipulate with the brush. lie had no new
teChnicalItieS to acquire, such Us were need
ed for the production Of various forms Of
engrayiug-technicaIi tiles that had hindered
many an artist from taking to plate work.
Proceeding to l.scribs the working of his
new invention, Professor lIerkomer stated
that on the polished surface OF Il copper plate
coated with silver, the artist painted his
picture with a thick black pigment resem-
bling printers ink. In the production Of
this painting he used brushes, feathers, bits
of wood, his finger tIp-in fact anything that
would enable INN to get the desired effect.
So far, it was a positive process, requiring,
therefore, no reversion of the subject on the
Iliilt-dl lIlcSLlll lbtt bOpI " INC dllot. All
examination of the painted plate showed that
the ink was on the surface IN different de.
grees of thickness, aud in this variety of
depth in the ink lay the first vital point of
the invention. The artist, however, need in
no way think of his necessary condition; it
a without conscious effort in the making
of his tones and gradations. This painted
surface. with the ink still wet, or soft, was
then busted over with q particular granulatei
powder, until neither the black paint, nor the
brighter parts Of tile plate were visible. A
knock on the back Of The plate and the sub
Sequent use If a soft cnmel-hair brush remov.
ed the superlIuous powder. As the powder
contained both coaIse md fine particles, it
stuck to the various parts IN the most dis.
criminatiye way. the cotrser grain adhering
to the parts where the ink happened to be
thick, and the timer where the ink was less,
such as in the gray or light tones. Thus
there was now secured a painted picture dust
ed with a powder, which g%ranulated the paint
ed touches imperfect proportion to their depth
of tone. without, however, in any way altering
their autographs character. But it caused
the paint to cover new technical ground, and
was the first stepping stone towards the CON
version Of the painted surface into a printing
surface, In the third stage there was taken
of this graduated surface a metallic mould"
or in other words. an electrotype. Such was
the conductibiIity Of this surface that (all
things being right in ten minutes a blush
of copper would spread over the whole sur
face when subjected to the electric bath.
This settled in and repeated the most minute
c~revices and interstices. The plate was left
in the bath until the copper deposit was as
thick as an ordinary printing plate. By FL
ing the edges the deposited plate was separat-
ed from the original painted plate, and in the
former was obtained an exact negative or
mould of the painted aud powdered surface,
from which, by the ordinary methods of cop
narnlate nrintinn q nerfect rpnrnductinn Of