I

Dissolve 1 ounce of gum arabic in 6 ounces water, and strain. This is the mucilage. For Black Color use drop black, powdered, and ground with the mucilage to extreme fineness; for Blue, ultramarine is used in the same manner; for Green, emerald green: for White, flake white; for Red, vermilion, lake, or carmine; for Yellow, chrome yellow. When ground too thick they are thinned with a little water. Apply with a small brush.

II

Triturate together 1 pint pine soot and 2 pints Prussian blue with a little glycerine, then add 3 pints gum arabic and sufficient glycerine to form a thin paste.

Blue Stencil Inks

The basis of the stencil inks commonly used varies to some extent, some preferring a mixture of pigments with oils, and others a watery shellac basis. The basis:

I

Shellac............ 2 ounces

Borax............. 1.5 ounces

Water............. 10 ounces

Boil together until 10 ounces of solution is obtained. The coloring:

Prussian blue...... 1 ounce

China clay......... 0.5 ounce

Powdered acacia. .. 0.5 ounce Mix thoroughly and gradually incorporate the shellac solution.

II

Prussian blue......     2 ounces

Lampblack........     1 ounce

Gum arabic........     3 ounces

Glycerine, sufficient.

Triturate together the   dry powders and then make into a suitable paste with glycerine.

Indelible Stencil Inks

I

Varnish such as is used for ordinary printing ink, 1 pound; black sulphuret of mercury, 1 pound; nitrate of silver, 1 ounce; sulphate of iron, 1 ounce; lampblack, 2 tablespoonfuls. Grind all well together; thin with spirits turpentine as desired.

II

Sulphate of manganese, 2 parts; lampblack, 1 part; sugar, 4 parts; all in fine powder and triturated to a paste in a little water.

III

Nitrate of silver, 1/4 ounce; water, 3/4 ounce. Dissolve, add as much of the strongest liquor of ammonia as will dissolve the precipitate formed on its first addition. Then add of mucilage, 1.5 drachms, and a little sap green, syrup of buckthorn, or finely powdered indigo, to color. This turns black on being held near the fire, or touched with a hot iron.