The best black ink to use for drawings is China ink rubbed down by working with a circular motion aud light pressure on the slab. Heating the slab or leaning heavily upon the stick makes the ink muddy and prevents it running freely. For ink that is to be used for all papers-drawing paper, Bristol board, or tracing paper-nothing should be added; but for cloth tracings a little oxgall or soap should be added, as it helps in causing the ink to flow. Also, sprinkle the tracing cloth with dry chalk and rub it well in afterwards, dusting it off to get as much of the oil out of the cloth as possible. "Artists' Black" is a liquid ink said to be specially suitable for drawings intended for process reproduction. It can be used equally well for finished drawings on cloth or other tracings; it has a dull black finish, whereas the China ink has a glossy black appearance.