oyed, but it is usual to tint brass work with yellow. Cast
iron with India ink, wrought iron with Prussian blue, steel with as
light purple tint produced by mixing India ink, Prussian blue and a
tinge of crimson lake. Copper is tinted red. On plane surfaces an even
tint of color is laid, but if the surfaces are cylindrical they are
usually colored deeper at and near the circumference, and are tinted
over the colors with light tints of India ink to show their cylindrical
form.

If a drawing is to be colored or shaded with India ink the paper should
be glued all around its edges to the drawing board, and then dampened
evenly all over with a sponge, which will cause the paper to shrink and
lay close to the surface of the drawing board. If, in applying a color
or a tint, the color dries before the whole surface is colored, the
color will not be of an equal shade; hence it is necessary before
applying the color to dampen the surface, if it is a large one, so that
the color at one part shall not get dry before there has been time to go
over the whole surface; a more even depth of color is attained by the
application of several coats of a light tint, than with one coat, giving
the full depth of color. But if the paper is not allowed to dry
sufficiently between the coats, or if it has been made too wet previous
to the application of the colors, it will run in places, leaving other
hollows into which the color will flow, making darker-colored spots. To
avoid this the paper may be dried somewhat by the application of clean
blotting paper.

To maintain an even shade of color, it is necessary to slightly stir up
the color each time the brush is dipped into the color saucer or
palette, especially when the coloring is composed of mixed colors,
because the coloring matter is apt to separate from the water and sink
to the bottom.

So, also, in mixing colors it is best to apply the end of the color to
the surface of the palette and not to apply the brush direct to the cake
of color, because the color is more completely mixed by contact with
the palette than it can be by the brush, which may retain a speck of
color that will, unless washed out, make a streak upon the drawing.

To graduate the depth of tint for a cylindrical surface, it is best to
mix several, as, say three depths or degrees of tint, and to first use
the darkest, applying it in the direction in which the piece is to be
shaded darkest. The width this dark application s