Jelly, Ta′pioca. As Sago jelly, but using tapioca in lieu of sago.
JERVINE. C60H5N2O5 An alkaloid discovered in 1837, by Simon, in the root of the Veratrum album, and by Mitchell, in 1874, in the root of the Veratrum viride. Dr H. C. Wood, jun., describing the physiological effects of jervine, says they consist “in general weakness, lowering of arterial pressure, a slow pulse, profuse salivation, and finally convulsions.” Jervine was analysed by Will, who ascribed to it the above composition.
JES′UIT’S BARK. See Cinchona.
JESUIT’S DROPS. See Drops.
JESUIT’S POWDER. Powdered cinchona bark.
JET. A variety of mineral bituminous carbon, very hard, and susceptible of a fine polish.
JEW′ELS. See Diamond, Emerald, Gems, &c.
JEWEL′RY. The gold in articles of jewelry, whether solid or plated, which are not intended to be exposed to very rough usage, is generally ‘coloured,’ as it is called in the trade. This is done as follows:—
1. (Red gold colour.) The article, after being coated with the amalgam, is gently heated, and, whilst hot, is covered with gilder’s wax; it is then ‘flamed’ over a wood fire, and strongly heated, during which time it is kept in a state of continual motion, to equalise the action of the fire on the surface. When all the composition has burned away, the piece is plunged into water, cleansed with the ‘scratch-brush’ and vinegar, and then washed and burnished. To bring up the beauty of the colour, the piece is sometimes washed with a strong solution of verdigris in vinegar, next gently heated, plunged whilst hot into water, and then washed, first in vinegar, or water soured with nitric acid, and then in pure water; it
is, lastly, burnished, and again washed and dried.