The forces of attraction and repulsion exercised by a magnet. By Ampere’s theory it is identical with the forces of attraction and repulsion of electric currents.

Magnetic induction; the number of lines of force that pass through a magnetic circuit. Synonym–Magnetic Flow.

A two-fluid theory of magnetism has been evolved, analogous to the two-fluid theory of electricity. It assumes north fluid or “red magnetism” and a south fluid or “blue magnetism.” Each magnetism is supposed to predominate at its own pole and to attract its opposite. Before magnetization the fluids are supposed to neutralize each other about [...]

The successive rows of polarized molecules assumed to exist in magnetized iron. Each molecule represents an infinitely small magnet, and its north pole points to the south pole of the next molecule. Such a string or row is a theoretical conception based on the idea that the molecules in a magnet are all swung in [...]

The figures produced by iron filings upon paper or glass held near magnetic poles. By these figures the direction of lines of force is approximately given, and a species of map of the field is shown. (See Magnetic Field of Force–Magnetic Curves.)

A field of identical strength in all parts, such as the earth’s magnetic field. If artificially produced, which can only be approximately done, it implies large cross-section of magnet pole in proportion to the length of the magnetic needle affected by it, which is used in determining its uniformity.

The field of force established by a magnet pole. The attractions and repulsions exercised by such a field follow the course of the electro- magnetic lines of force. (See also Field of Force.) Thus the tendency of a polarized needle attracted or repelled is to follow, always keeping tangential to curved lines, the direction of [...]

A locus of the earth’s surface where the magnet has no tendency to dip. It is, approximately speaking, a line equally distant from the magnetic poles, and is called also the aclinic line. It is not a great circle of the earth.

The qualities of the terrestrial magnetism at any place as expressed in its action upon the magnetic needle. Three data are involved. I. The Declination or Variation. II. The Inclination or Dip. III. The Force or Intensity. I. The Declination is the variation expressed in angular degrees of the magnetic needle from the true north [...]

A break or gap in a magnetic circuit. To make a complete circuit the iron or other core must be continuous. If the armature of a horseshoe magnet is in contact with both poles the continuity is complete. If the armature is not in contact magnetic continuity gives place to discontinuity. It is an attribute [...]