Public ledger. [volume] (Memphis, Tenn.) 1865-1893, 1872-08-14
The Late Aurorat Display Is ID
POrtentous?-The Hurricane Sea.
SON tn the Tropics.

ROrtent0usy-Tne Aurrfcone sea
SON fn the Tropics.
From the New York HERALD af
The magnificent auroral display o.
last Saturday night will furnish scien
lists new opportunity for studying the
probable cause and significance of the
phenomenon. AS we have already no
ticed, this aurora was brillintly visible
over large portion of the country
from the lakes as far south as Washing
ton-and was reported by some as the
most extraordinary one ever remembered
in their respective localities.
The most satisfactory explanation OF
these splendors in the northern skies
seems to be that which connects them
with the reflection of electric discharges
from the microscopic ice crystals, which
compose the delicate cirrus clouds in
the upper atmosphere. These crystals
of condensed vapor, so minute as to
defy any but the most practised obser-
yer, act as screen for the reflection of
light; and the deposition of watery vapor
from the lofty equatorial current pro-
duces the lightning discharge.
But whether this be the true origin of
auroras or not they are said by meteor
ologists TO be excellent and almost un-
failing premonitors of atmospheric dis
turbances, and often of the most disas-
trous gales aud cyclones. 1t has been
carefully observed at the Imperial OBJ
servatOry at Paris, that the perturba-
tons of the magnetic needle are Joined
inseparably with widespread auroras and
the consequent disturbances of the tele-
graphic wires. 1t is also clearly estab-
lished, by scientific observation, that the
display OF the Aurora Borealis indicates
a general movement of the atmosphere
in high latitudes, and especially such a
movement over the Atlantic Ocean.
The electric discharges in the high north
seem to register and reveal the fact that
a vast body of equatorial and vapor-
laden air has invaded the polar territory
and begun to invite counter movement,
and repelling activity of the colder at
mosphere, resulting, as all experiences
shows, in the immediate and usually
successful attempt to expel the intruding
mass. This is followed by the down
rush Of polar air over the tropics
themselves, as is beautifully shown by
the late weather reports of the Sig
nal Office. These reports attest the
flow of a vast current of cold air
from the northern part of the Continent
descending upon the entire country east
of the Mississippi overruning the South
ern and Gulf coasts. 1t is by no means
improbable this vast torrent of cool,
semi-polar air, as it makes its Eruption
into the hot, watery air Of the West In
dies, may produce violent disturbance,
either by mechanical conflict or by the
sudden condensation of immense guam
titles of aqueous vapor. In the weather
preceding the celebrated Royal Char
ter" gale, which swept over England in
1859, the thermometer for a few days
previous was very low for the season,
and over large part of the globe au-
roras and meteors had been peculiarly
abundant and resplendent; and even for
a week or ten days previous the English
skies had been illuminated by the blood
red streamers Of Aurora. 1t is so COM
monty observed by seamen that such
premonitions Of storms are reliable that
they have long interpreted the ooinci-
dence as casual in its nature. This is
the hurricane season for the West In.
dies, and we may be now on eur guard
against those tropical storms which gen.
Grated in the hot seas, move westwardly
on our Southern and Gulf coasts every
year, and strew them with death, DESC
lation and many noble wrecks.