a small sponge. When the paper is quite transparent,
the oil in excess is removed by pressure between sheets of blotting paper,
and the paper dried before the fire or spontaneously. The design so
treated is not in the least injured, for it assumes its primitive
condition by dissolving the oil from the paper by immersion into strong
alcohol, which it is necessary to renew once or twice, then rinsing in
alcoholized water if the drawing be in India ink, or simply in water in
the case of an engraving, and finally drying between sheets of blotting
paper.

Instead of an alcoholic solution of castor oil, vaseline can be employed.
The paper is more transparent.

The method by which are made negative drawings, that is, those which can
be used as negative cliches to reproduce the design in black lines on a
white ground, is thus described by Mr. Cheysson, wlio originated it, in a
manual published by the Department of Public Works of France, from which
we have borrowed most of the above instructions for the drawing of designs
suitable for the photo-reproduction processes:(4)

"One can avoid the necessity of making a negative from the original
drawing by transforming the drawing itself into a negative."

"To that effect it suffices to draw with lithographic ink, then to cover
the paper with aniline brown, and, after drying, to wash it with
turpentine oil which dissolves the lithographic ink without altering the
aniline. The lines appear then white on a brown ground impervious to
light (that is, non-actinic). The design is thus transformed into a
negative, and can yield positive impressions with paper sensitized with
silver salts, the ferriprussiate or the bichromate of potash. The
lithographic ink should be very black and the lines well fed."

"When the drawing is finished it is placed on a board lined with sheets of
blotting paper, then one spreads all over it the aniline brown with a
brush, and, lastly, after drying, the paper is carefully rubbed with a
bung of cotton or a rag imbued with turpentine until the lines of the
design are dissolved."

In our practice we have often taken a negative cliche from drawings made
in the ordinary manner, without the aid of the camera obscura (which would
have been too expensive for drawings of a certain size), by simply
printing a proof by contact on plain or albumenized silvered paper, and
fixing, without toning, in a new solution of sodium thiosulphate, then
washing as usual. Th