Pittsburg dispatch. [volume] (Pittsburg [Pa.]) 1880-1923, 1892-07-26
THE AURORA IN DISPUTE.
WRITTEN FOR THE DISPATCH ]


The auroral exhibition on the night OF
July 10 was on a much grander scale than
usual. The magnetic arch was very clearly
defined, the pecils or columns OF flame came
and went in quick succession; but the finest
feature was the rapid dashfng Of the white,
misty light, which might be likened to the
storm-tosshd surges of some magnetic ocean.
This feature, in its rapidity OF motion, ex-
ceeded anything of the kind ever before OBJ
served by the writer, and 1t is evident that
the phenomenon was unusually near the
earth.
There were also the peculiar coloring
tints that are hard to define, probably our
basic co;ors, but with such fine distinctions
of shading as to suggest something outside
of our primary order.
All storms are disturbed natural forces
seeking equilibrium. Winds represent un-
equal atmospheric temperature and pressure
in the effort to equalize again, and when
this is accomplished there is quiescence
until this equilibrium is again too much dis
turbed.
Causes Of the Aurora.
Lightning and thunder are tho phenomena
that represent the disturbed electrical forces
again rogaining normal relationship, which,
when once established, insures tranquility
until another ebulition comes with similar
known as the aurora horealis, is simply the
exhibition that attends the restoration of
the disturbed magnetic forces of a given
area, and is generally found attendant to Il
sudden change of temperature, either from
cold to warm, Or warm to cold, preferably
the latter. Unlike winds or thunder and
lightning. which are equally recognizable in
the day time or night time, and the first
mentioned, during cloudy as well as in clear
weather, this exhibition is only seen on a
clear night though the forces may be at
work at any time.
Only when the disturbance is much
greater than usual, when the magnetic cur
rents poleward are greatly inter!ered with,
is the storm of such magnitude as to be WIS.,
fble. We may consider the equatorial belt
rs the magnetic "divide," over which an
auroral display would necessarily be very
unusual, If not altogether impossible.
Tho magnetic current there receives its
initial impulse, or rather, its impulse, which
is really from the sun, there finds it's initial
effect, and, having the entire circumference
Of the globle and consequently being most
unconcentrated, is least liable to disturb
ance.
But, as from all sides the current travels
poleward, it more and more concentrates,
until a latitude is reached where an occa-
sional storm is manifested, and this ten
dency increases until, as we go within the
polar circles, the long polar nights arc one
continuous luminous display of almost in
describable grandeur.
An Invisible Exhibition.
The Same thing is going on during the
long polar day, but is, OF course, invisible.
Since the above was written THE
DISPATCH has come to hand, with Prof.
Brashear's explanation. referring such phe-
nomena to solar disturbances.
Some years ago the writer had occa sion to
differ from about the entire corps of scien-
tific people in this country, as well as in
Europe, on what caused the singular after
sunset glows which took place in October and
November, 1888. Whether by chance or what
ever he had the satisfaction of seeing one by
one abandon his first announced solution
and take the ground announced within three
days of the commencement of the phen-
omena. The potency of the sun spot, or the
solar phenomena of whatever character,
should not be limited or restricted
in its magnetic generative or what
ever 1t is that We recognize as the
aurora borealis, to just given number Of
hours, not to given locality. The hypothe-
sis-if it has reached such a stage-utterly
fails to explain the continuous magnetic
displays in hich northern regions.
The writer prefers to stand by his position,
which he thinks he has reached by a careful
analysis, and in doing this no discourtesy is
intended to other investigators. Let US
gather what we can on the ediamond-studded
shores of knowledge and devoutly and
reverently lay what contributions we may.
to the common store Of means to lift us
higher to a knowledge of the universe. n.