Although the direct object of these is to keep the teeth clean and white, they also prevent decay, if it is only by force of mere cleanliness, and in this way (and also by removing decomposing particles of food) tend to keep the breath sweet and wholesome. The necessary properties of a tooth powder are cleansing power unaccompanied by any abrading or chemical action on the teeth themselves, a certain amount of antiseptic power to enable it to deal with particles of stale food, and a complete absence of any disagreeable taste or smell. These conditions are easy to realize in practice, and there is a very large number of efficient and good powders, as well as not a few which are apt to injure the teeth if care is not taken to rinse out the mouth very thoroughly after using. These powders include some of the best cleansers, and have hence been admitted in the following recipes, mostly taken from English collections.

I

Charcoal and sugar, equal weights. Mix and flavor with clove oil.

II

Charcoal.....   156 parts

Red kino.....   156 parts

Sugar........       6 parts

Flavor with peppermint oil.

III

Charcoal.....   270 parts

Sulphate of quinine.. . .       1 part

Magnesia....       1 part Scent to liking.

IV

Charcoal.....     30 parts

Cream of tartar........       8 parts

Yellow cinchona bark      4 parts

Sugar.......     15 parts

Scent with oil of cloves.

V

Sugar.......   120 parts

Alum........     10 parts

Cream of tartar........     20 parts

Cochineal....       3 parts

VI

Cream of tartar........1,000 parts

Alum........   190 parts

Carbonate of magnesia..   375 parts

Sugar.......   375 parts

Cochineal....     75 parts

Essence Ceylon cinnamon......     90 parts

Essence cloves.....     75 parts

Essence English peppermint. . .     45 parts

VII

Sugar.......   200 parts

Cream of tartar........   400 parts

Magnesia.. . .   400 parts

Starch.......   400 parts

Cinnamon. ..     32 parts

Mace.......     11 parts

Sulphate of quinine.. . .     16 parts

Carmine.....     17 parts

Scent with oil of peppermint and oil of rose.