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Magnesium
(Mag*ne"si*um) n. [NL. & F. See Magnesia.] (Chem.) A light silver-white metallic element,
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, 24.4. Specific gravity, 1.75.
Magnesium sulphate. (Chem.) Same as Epsom salts.
Magnet
(Mag"net) n. [OE. magnete, OF. magnete, L. magnes, - etis, Gr. Magnh^tis li`qos a magnet,
metal that looked like silver, prop., Magnesian stone, fr. Gr. Magnhsi`a, a country in Thessaly. Cf. Magnesia,
Manganese.]
1. The loadstone; a species of iron ore (the ferrosoferric or magnetic ore, Fe3O4) which has the property
of attracting iron and some of its ores, and, when freely suspended, of pointing to the poles; — called
also natural magnet.
Dinocrates began to make the arched roof of the temple of Arsinoë all of magnet, or this loadstone. Holland.
Two magnets, heaven and earth, allure to bliss,
The larger loadstone that, the nearer this. Dryden. 2. (Physics) A bar or mass of steel or iron to which the peculiar properties of the loadstone have been
imparted; — called, in distinction from the loadstone, an artificial magnet.
An artificial magnet, produced by the action of a voltaic or electrical battery, is called an electro-magnet.
Field magnet (Physics & Elec.), a magnet used for producing and maintaining a magnetic field; —
used especially of the stationary or exciting magnet of a dynamo or electromotor in distinction from that
of the moving portion or armature.
Magnetic
(Mag*net"ic Mag*net"ic*al) a. [L. magneticus: cf. F. magnétique.]
1. Pertaining to the magnet; possessing the properties of the magnet, or corresponding properties; as, a
magnetic bar of iron; a magnetic needle.
2. Of or pertaining to, or characterized by, the earth's magnetism; as, the magnetic north; the magnetic
meridian.
3. Capable of becoming a magnet; susceptible to magnetism; as, the magnetic metals.
4. Endowed with extraordinary personal power to excite the feelings and to win the affections; attractive; inducing
attachment.
She that had all magnetic force alone. Donne. 5. Having, susceptible to, or induced by, animal magnetism, so called; as, a magnetic sleep. See Magnetism.
Magnetic amplitude, attraction, dip, induction, etc. See under Amplitude, Attraction, etc. —
Magnetic battery, a combination of bar or horseshoe magnets with the like poles adjacent, so as to act
together with great power. — Magnetic compensator, a contrivance connected with a ship's compass
for compensating or neutralizing the effect of the iron of the ship upon the needle. — Magnetic curves,
curves indicating lines of magnetic force, as in the arrangement of iron filings between the poles of a
powerful magnet. — Magnetic elements. (a) (Chem. Physics) Those elements, as iron, nickel, cobalt,
chromium, manganese, etc., which are capable or becoming magnetic. (b) (Physics) In respect to
terrestrial magnetism, the declination, inclination, and intensity. (c) See under Element. — Magnetic
equator, the line around the equatorial parts of the earth at which there is no dip, the dipping needle
being horizontal. — Magnetic field, or Field of magnetic force, any space through which a magnet
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