from
The Collaborative International Dictionary of English v.0.48
Magnesium \Mag*ne"si*um\, n. [NL. & F. See {Magnesia}.] (Chem.)
A light silver-white metallic element of atomic number 12,
malleable and ductile, quite permanent in dry air but
tarnishing in moist air. It burns, forming (the oxide)
magnesia, with the production of a blinding light (the
so-called magnesium light) which is used in signaling, in
pyrotechny, or in photography where a strong actinic
illuminant is required. Its compounds occur abundantly, as in
dolomite, talc, meerschaum, etc. Symbol Mg. Atomic weight,
24.305. Specific gravity, 1.75.
[1913 Webster]
{Magnesium sulphate}. (Chem.) Same as {Epsom salts}.
[1913 Webster]