The dentifrices for preventing caries, among which the thymol preparations are the most prominent, deserve special attention. The most celebrated physicians have long since recognized thymol as an antiseptic, it being much used in hospitals, and is frequently preferred to carbolic acid. For this reason thymol preparations should be used for preserving the teeth. They render good service, especially in the case of hollow teeth, as they remove the foul odor and protect the sound teeth from becoming hollow. For cleansing artificial teeth thymol tooth-water can be especially recommended. Great care should, therefore, be exercised in the preparation of these thymol dentifrices. On the other hand, according to medical opinions, dentifrices containing salicylic acid cannot be recommended, the acid, it is claimed, being very injurious to the enamel of the teeth. Glycerin, which occurs in several receipts for dentifrices and mouth-waters, fulfills a double object; on the one hand, its action upon the teeth and mouth is beneficial, and, on the other, it covers the naturally bitter taste of many substances contained in the preparations, and thus makes them more agreeable to use. The receipts for dentifrices and mouth-waters here given have been thoroughly tested, and can be highly recommended. _Tooth and mouth waters._ _Thymol tooth-water._--Alcohol of best quality 5 quarts, chemically pure glycerin of 28° B. 17½ ozs., crystallized thymol 1 oz., white thyme oil and best peppermint oil each 1¼ ozs., tinctures of arnica and guaiacum each 1¾ ozs., cochineal tincture, for coloring, 2¾ to 3½ ozs. Bring all the ingredients into a glass balloon, shake thoroughly, and protect the liquid from sunlight. The cochineal tincture is prepared from 14 ozs. of cochineal and 1 quart of alcohol of best quality, the arnica tincture from 2 lbs. of arnica root and 2½ quarts of alcohol of best quality, and the guaiacum tincture from 5¼ ozs. of guaiacum-wood and 1 quart of alcohol of best quality. _Eau dentifrice Botot._--Alcohol of best quality 5 quarts, chemically pure glycerin of 28° B. 17¾ ozs., peppermint oil 2 ozs., clove oil 11 drachms, anise-seed oil 5 drachms, ratany tincture and vanilla tincture each 5¼ ozs., Peruvian bark tincture 1¾ ozs., sanders-wood tincture, as coloring matter, 3½ ozs. Proceed as above. The sanders-wood tincture is prepared by macerating 5¼ ozs. of red sanders wood with 1 quart of alcohol. _Eau dentifrice Orientale._--Alcohol of best quality 5 quarts, peppermint oil and rose-geranium oil each 1¼ ozs., clove oil 11¼ drachms, _extrait rose_ and ratany tincture each 3½ ozs., vanilla tincture 1¾ ozs. Proceed as above and color rose color with corallin tincture. The ratany tincture is prepared from 17½ ozs. of ratany root and 1 quart alcohol, and the corallin tincture from 17½ ozs. of corallin and 1 quart alcohol.