This section is from the book "The Boy Mechanic Vol. 2 1000 Things for Boys to Do", by Popular Mechanics Co.. Also available from Amazon: The Boy Mechanic, Vol2: 1000 Things for Boys to Do.
Graduates that have been in use a long time, especially for measuring alkalies, become unreadable. The graduations are easily restored in the following manner: Moisten a small piece of absorbent cotton with a solution of white shellac, cut in alcohol. Rub this well into all the etched parts and allow to dry for about two minutes, then rub in a fine whiting or litharge with an old toothbrush. If red is desired, use rouge; if black is preferred, use lampblack or powdered graphite. When dry, wipe off the excess pigment with a cloth moistened in alcohol. - Contributed by A. C. Norris, Rockford, Ill.