Wax 16 parts.
Tallow 6 --
Hard tallow soap 6 --
Shell-lac 12 --
Mastic in tears 8 --
Venice turpentine 1 --
Lamp black 4 --
The mastic and lac, previously ground together, are to be heated with
care in the turpentine; the wax and tallow are to be added after they
are taken off the fire, and when their solution is effected, the soap
shavings are to be thrown in. Lastly, the lamp black is to be well
intermixed. Whenever the union is accomplished by heat, the operation is
finished; the liquor is left to cool a little, then poured out on
tables, and, when cold, cut into square rods.
Lithographic ink of good quality ought to be susceptible of forming an
emulsion so attenuated, that it may appear to be dissolved when rubbed
upon a hard body in distilled or river water. It should be flowing in
the pen, not spreading on the stone; capable of forming delicate traces,
and very black to show its delineations. The most essential quality of
the ink is to sink well into the stone, so as to re-produce the most
delicate outlines of the drawing, and to afford a great many
impressions. It must therefore be able to resist the acid with which the
stone is moistened in the preparation, without letting any of its greasy
matter escape.
M. de Lasteyrie states that after having tried a great many
combinations, he gives the preference to the following:--
Tallow soap, dried 30 parts.
Mastic, in tears 30 --
White soda of commerce 30 --
Shell-lac 150 --
Lamp black 12 --
The soap is first put into the goblet and melted over the fire, to which
the lac being added fuses immediately; the soda is then introduced, and
next the mastic, stirring all the while with a spatula. A brisk fire is
applied till all these materials be melted completely, when the whole is
poured out into the mould.
The inks now prescribed may be employed equally with the pen and the
hair pencil, for writings, black-lead drawings, _aqua tinta_, mixed
drawings, those which represent engravings on wood (wood cuts), &c. When
the ink is to be used it is to be rubbed down with water, in the manner
of China ink, till the shade be of the requisite depth. The temperature
of the place ought to be from 84° to 90° Fahr., or the saucer in which
the ink-stick is rubbed should be set in a heated plate. No more ink
should be dissolved than is to be used at the time, for it rarely keeps
in the liquid state for 24 hours; and it should be covered or corked up.
_Autographic paper._--Autography, or the operation by which a writing or
a drawing is transferred from paper to stone, presents not merely a
means of abridging labour, but also that of _re_verting the writings or
drawings into the direction in which they were traced, whilst, if
executed directly upon the stone, the impression given by it is
_in_verted. Hence, a writing upon stone must be inverted from right to
left to obtain direct impressions. But the art of writing thus is
tedious and difficult to acquire, while, by means of the autographic
paper and the transfer, proofs are obtained in the same direction with
the writing and drawing.
_Autographic ink._--It must be fatter and softer than that applied
directly to the stone, so that though dry upon the paper, it may still
preserve sufficient viscidity to stick to the stone by mere pressure.