SCIOPTICON MANUAL.
139
The preceding article on drawing and painting magic
lantern slides has been contributed by an expert pre¬
eminently qualified to assist us in overcoming its ap¬
parently insuperable difficulties.
It may be proper here to state that we now furnish a
varnish to take the place of No. 1 and No. 2, which
answers equally well with but once flowing. Like No.
2 it must be dried by heat to prevent what is called
“ chilling.” The operation can be best performed in a
dry atmosphere which is free from dust.
A Copying Camera.—A private letter from Prof. W.
A. Boles, of Shelbyville, Ind., Superintendent of Schools,
contains further valuable information in this direction,
and a description of a new instrument of his own inven¬
tion. By permission the following extracts are given
in the interest of home production.
“With this mail I send you a specimen of my drawing
on gelatine-coated glass, for use in the Sciopticon. After
the coating of gelatine is perfectly dry, I sand-paper it
with the finest article I can get, and after the picture
is drawn, float it with your No. 1 varnish. . . .
“I made an upright camera-obscura, using the lens
from the Sciopticon. The picture to be copied is placed
beneath, in the sunlight if possible, and the image is
thrown upward so that I can trace the outlines quite at
my ease. On the roughened gelatine a fine steel pen
and the ordinary black ink I am now using mark beauti¬
fully, and the shading is done with a lead pencil. By
tracing the image of the picture, in the little darkened
chamber, I avoid the trouble from the slipping of tho
glass and the different angles of observation consequent
upon superposition. This plan has also the additional
advantage of enabling me to reduce or enlarge a draw¬
ing to any desirable size.