ELEMENTS

The old chemists applied t^'s term li certain imaginary principles or e ences of matter; suck as fire, water, earth, and air. The elements of the alchemists are salt, sulphur, and mercury. The term element is now used as synonymous v/i\h simple or unde compounded body; that is, a substance which we cannot resolve inn; simpler forms of matter. Tne present list of elements includes all the metals, and the following substances— oxygen, chlorine, iodine, bromine, fluorine, hydrogen, nitrogen, suling in phur,all to phosphorus,fifty-four,carbon,exclusive selenium,of the and'imponderable boron; aiuoi.mforms of matter. See Equivalents, Chemical [s. 406]