Schobel recommends the following inks for marking articles of glass, glass slips for microscopy, reagent flasks, etc., in black:

I

Sodium silicate.....1 to 2 parts

Liquid India ink 1 part

For white: II

Sodium water glass 3 to 4 parts Chinese white.....         1 part

Instead of Chinese white, a sufficient amount of the so-called permanent white (barium sulphate) may be used. The containers for these inks should be kept air-tight. The writing in either case is not attacked by any reagent used in microscopical technique but may be readily scraped away with a knife. The slips or other articles should be as near chemically clean as possible, before attempting to write on them.

According to Schuh, a mixture of a shellac solution and whiting or precipitated chalk answers very well for marking glass. Any color may be mixed with the chalk. If the glass is thoroughly cleaned with alcohol or ether, either a quill pen or a camel's-hair pencil (or a fresh, clean steel pen) may be used.

Ink on Marble

Ink marks on marble may be removed with a paste made by dissolving an ounce of oxalic acid and half an ounce of butter of antimony in a pint of rain water, and adding sufficient flour to form a thin paste. Apply this to the stains with a brush; allow it to remain on 3 or 4 days and then wash it off. Make a second application, if necessary.