Cooley's Cyclopædia of Practical Receipts and Collateral Information in the Arts, Manufactures, Professions, and Trades..., Sixth Edition, Volume II

by Arnold James Cooley; Richard Vine Tuson

2. To reduce Fahrenheit’s degrees to Centigrade:

(Fahr.° - 32) × 5 / 9 = Cent.°

3. To reduce Reaumur’s to Fahrenheit’s:

Reau.° × 9 / 4 + 32 = Fahr.°

4. To convert Fahrenheit’s to Reaumur’s:—

(Fahr.° - 32) × 4 / 9 = Reaumur.°

Thermometers intended to register extreme degrees of heat are called PYROMETERS (which see)

THIBANT’S BALSAM. For wounds. Digest flowers of St John’s wort, one handful in ¹⁄₂ pint of rectified spirit; then express the liquor, and dissolve in it myrrh, aloes, and dragon’s blood, of each 1 dr., with Canada balsam, ¹⁄₂ oz.

THO′RIUM. Th. Syn. Thorinum. A very rare element, belonging to the group of earthy metals. Metallic base of thoria. It is obtained by the action of potassium on the chloride of thorium, and washing the resulting mass in water.

THORN-APPLE. See Datura.