PLATINUM n.
A metallic element, intermediate in value between silver and gold, occurring native or alloyed with other metals, also as the platinum arsenide (sperrylite). It is heavy tin-white metal which is ductile and malleable, but very infusible, and characterized by its resistance to strong chemical reagents. It is used for cr…
POSITIVE a.
-- Positive motion (Mach.), motion which is derived from a driver through unyielding intermediate pieces, or by direct contact, and not through elastic connections, nor by means of friction, gravity, etc.; definite motion. -- Positive philosophy. See Positivism. -- Positive pole. (a) (Elec.) The pole of a battery o…
PROPIONIC a.
m, or designating, an organic acid which is produced in the distillation of wood, in the fermentation of various organic substances, as glycerin, calcium lactate, etc., and is obtained as a colorless liquid having a sharp, pungent odor. Propionic acid is so called because it is the first or lowest member of the fatty a…