Any of these powders may, by the addition of mucilage of gum arabic, be made into lozenges or buttons—the "ink buttons" or "ink stones" in use abroad and much affected by travelers.

The following makes a good serviceable black ink, on macerating the powder in 100 times its weight of rain or distilled water for a few days:

I

Powdered gallnuts .. 16 parts

Gum arabic......... 8 parts

Cloves............. 1 part

Iron sulphate....... 10 parts

Put into an earthenware or glass vessel, cover with 100 parts of rain or distilled water, and set aside for 10 days or 2 weeks, giving an occasional shake the first 3 or 4 days. Decant and bottle for use.

The following is ready for use instantly on being dissolved in water:

II

Aleppo gallnuts..... 84 parts

Dutch Madder...... 6 parts

Powder, mix, moisten, and pack into the percolator. Extract with hot water, filter, and press out. To the filtrate add 4 parts of iron acetate (or pyroacetate) and 2.5 parts of tincture of indigo. Put into the water bath and evaporate to dryness and powder the dry residue.