Red Printing Ink.
Red printing ink may be made in this way:—Boil linseed oil until smoke is given off. Set the oil then on fire, and allow it to burn until it can be drawn out into strings half an inch long. Add one pound of resin for each quart of oil, and one-half pound of dry, brown soap cut into slices. The soap must be put in cautiously, as the water in the soap causes a violent commotion. Lastly, the oil is ground with a sufficient pigment on a stone by means of a muller. Vermilion, red lead, carmine, Indian red, Venetian red, and the lakes are all suitable for printing inks.