CADMIUM n.
A comparatively rare element related to zinc, and occurring in some zinc ores. It is a white metal, both ductile and malleable. Symbol Cd. Atomic weight 111.8. It was discovered by Stromeyer in 1817, who named it from its association with zinc or zinc ore. Cadmium yellow, a compound of cadmium and sulphur, of an intens…
CERIUM n.
A rare metallic element, occurring in the minerals cerite, allanite, monazite, etc. Symbol Ce. Atomic weight 141.5. It resembles iron in color and luster, but is soft, and both malleable and ductile. It tarnishes readily in the air.
CHROMIUM n.
A comparatively rare element occurring most abundantly in the mineral chromite. Atomic weight 52.5. Symbol Cr. When isolated it is a hard, brittle, grayish white metal, fusible with difficulty. Its chief commercial importance is for its compounds, as potassium chromate, lead chromate, etc., which are brilliantly colore…
COMPASSES n.
An instrument for describing circles, measuring figures, etc., consisting of two, or (rarely) more, pointed branches, or legs, usually joined at the top by a rivet on which they move.