would give even an approximate idea of the loss in heat incurred, as
in such case heat must be given off much more quickly, since there is,
in addition to the ordinary radiation, a very active carrying away of
heat by independent carriers going on, and since not only the
apparatus, but the air at some distance from it is heated in
consequence of the collisions which must occur.
Owing to this, in experiments with such a coil, a rise of temperature
can be distinctly observed only when the body connected to the coil is
very small. But with apparatus on a larger scale, even a body of
considerable bulk would be heated, as, for instance, the body of a
person; and I think that skilled physicians might make observations of
utility in such experiments, which, if the apparatus were judiciously
designed, would not present the slightest danger.
A question of some interest, principally to meteorologists, presents
itself here. How does the earth behave? The earth is an air condenser,
but is it a perfect or a very imperfect one--a mere sink of energy?
There can be little doubt that to such small disturbance as might be
caused in an experiment the earth behaves as an almost perfect
condenser. But it might be different when its charge is set in
vibration by some sudden disturbance occurring in the heavens. In such
case, as before stated, probably only little of the energy of the
vibrations set up would be lost into space in the form of long ether
radiations, but most of the energy, I think, would spend itself in
molecular impacts and collisions, and pass off into space in the form
of short heat, and possibly light, waves. As both the frequency of the
vibrations of the charge and the potential are in all probability
excessive, the energy converted into heat may be considerable. Since
the density must be unevenly distributed, either in consequence of the
irregularity of the earth's surface, or on account of the condition of
the atmosphere in various places, the effect produced would
accordingly vary from place to place. Considerable variations in the
temperature and pressure of the atmosphere may in this manner be
caused at any point of the surface of the earth. The variations may be
gradual or very sudden, according to the nature of the general
disturbance, and may produce rain and storms, or locally modify the
weather in any way.
From the remarks before made one may see what an important factor of
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