COLOIIRED.—Coloured inks are made by adding to the varnish already described, certain pig ments, of which the principal are as follows : Red: 5 oz. mineral orange-red, 2 oz. Chinese red.
Blue : 2 oz. celestial blue, 3 oz. marine blue.
Green : 2 oz. mineral green, 3 oz. chrome-green.
Brown: 2 oz. burnt umber, 1 on rose-pink.
Lilac: 1 oz. Prussian blue, 2 oz. Chinese red.
Pink : 2 oz. mineral pink, 1 oz. satin-white.
Orange : 2 oz. orange-red, 1 oz. flake-white, ground up with Canada balsam, and omitting the linseed-oil varnish.
Miscellaneous Inks.—Inks for writing on metallic surfaces may be made as follows:— (a) 1 part verdigris (acetate oteopper), 1 part sal ammoniac, part soot, 10 parts water ; stir well write with a quill. (b) 1 grm. sulphate of copper, dissolved in 20 grm. water ; add 2 drops hydro chloric acid, and enough solution of gum arabic to make the ink adhesive. To make the writing appear at once, add a little pyrogallic acid. Write with a copper pen. (c) Dissolve 2 oz. shellac in 1 pint alcohol, filter through chalk, and mix with finest lampblack; forma a jet-black, lustreless ink, insoluble in water. A violet ink for rubber stamps is made by mixing 2-4 dr. aniline violet
in 15 oz. alcohol and 15 oz. glycerine. Gold inks are made as follows :—(a) 24 leaves gold, I oz. bronze gold, 30 drops spirit of vine, 30 grin. honey, 4 dr. gum arabic, 4 oz. rain-water ; rub the gold with the honey and gum, and having mixed it with the water, add the spirit. (b) 1 part gold, 3 parts aqua regia ; mix, and evaporate till all the chlorine is given off; cool, and mix well with ether; thicken with naphtba or essential oils. An improved method of making gold and silver inks is to triturate the purified metallic powder with a solution of 1 part white gum arabic iu 4 parts distilled water, and 1 part potash water-glass.
Imports of Inks.—The value of the inka imported into the United Kingdom from all countries in 1879 was 8273/.
Bibliography.—W. Savage, Ink' (London : 1832).
(See Blacks ; Camphor ; Coal-tar Products ; Dyestuffs ; Pigments ; Printing and Engraving ; Resinous Substances ; Tannin.)