Lithographic chalk is only prepared in the solid form for drawing on paper direct or on stone. According to the nature of the work, it is harder or softer, fatter or leaner. The hard kinds, which are also usually leaner, contain more resin and less fat; the soft, on the contrary, more grease.
Fatty chalk is composed of—
| Wax | 30 | parts. |
| Marseilles soap | 24 | parts. |
| Tallow | 4 | parts. |
| Shellac | 1 | part. |
| Lampblack | 6 | parts. |
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Lean chalk is composed of—
| Wax | 12 | parts. |
| Marseilles soap | 8 | parts. |
| Tallow | 2 | parts. |
| Shellac | 10 | parts. |
| Lampblack | 4 | parts. |
For lithographic work a greasy ink is required in contradistinction to ordinary printing ink, which consists of linseed oil and lampblack, which would be called “lean.” For inking-up a photo-lithographic chromated gelatine print such an ink cannot be used. In order to obtain a good result in transferring, this ink must contain grease, soap, and resin.
Any good transfer ink can be used for a developing ink, as this is applied with a roller. It usually consists of equal parts of tallow, wax, soap, some resin, and as much litho ink as all the other ingredients put together.
That prepared by C. Kampmann, Technical Instructor in the K.K. Lehr- und Versuchsanstalt at Vienna, contains, besides the above-named ingredients, asphalt and gum elemi, and works well in practice.
Thin developing inks, which are distributed with a broad brush or a pad, can be prepared by diluting good transfer ink with equal quantities of wax, benzine, and turpentine.