terrestrial magnetism

Magnetism \Mag"net*ism\, n. [Cf. F. magn['e]tisme.]
   The property, quality, or state, of being magnetic; the
   manifestation of the force in nature which is seen in a
   magnet. At one time it was believed to be separate from the
   electrical force, but it is now known to be intimately
   associated with electricity, as part of the phenomenon of
   {electromagnetism}.
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   2. The science which treats of magnetic phenomena.
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   3. Power of attraction; power to excite the feelings and to
      gain the affections. "By the magnetism of interest our
      affections are irresistibly attracted." --Glanvill.
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   {Animal magnetism}, Same as {hypnotism}, at one time believe
      to be due to a force more or less analogous to magnetism,
      which, it was alleged, is produced in animal tissues, and
      passes from one body to another with or without actual
      contact. The existence of such a force, and its
      potentiality for the cure of disease, were asserted by
      Mesmer in 1775. His theories and methods were afterwards
      called mesmerism, a name which has been popularly applied
      to theories and claims not put forward by Mesmer himself.
      See {Mesmerism}, {Biology}, {Od}, {Hypnotism}.

   {Terrestrial magnetism}, the magnetic force exerted by the
      earth, and recognized by its effect upon magnetized
      needles and bars.
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