The news and herald. (Winnsboro, S.C.) 1877-1900, 1879-12-11
Tho Indian Summer.

Indian summer is certainly very char
actcristic and periodical phenomenon in all
these high American ATTITUDES, as it is in
Central Europe. though probably in less
marked degree, and there arc reasons for
believing that it excrts its softcning nllu-
enccs up to tho Arctic circle, tcmpcring the
ilrst waves of winter cold that tlcsccnds
upon Arctic America. But it does not ap-
pear to lavish its charms Oh the far South
or lower ATTITUDES of the United States,
where indeed, they are not much needed
Although it is often prolonged into Dcccm
Der when calm, hazy atmosphere fills the
sky, through which the sun, shorn of his
strength, sinks day after day, like a globe
OF fire. The Indian Summer at the Provin-
cal Observatory in Toronto, Canada, has
been occasionally recorded as early as the
9Th of October. The average date of it's
distinct appearance there. deducted from
fourteen years observation, is October 27.
Search for explanation of this phenomenon
has not escaped scientific investigation. As
either pole of the earth is turned around
the sun after the vcrnal equinox, and solar
effect increases in the direction of that pole
until thaw of the winters accumulated
Ice sets in, when an interval of cold occurs,
caused by the rapid absorption of solar heat,
and thus the frequent "cod spells of the
later spring months is often accounted for.
When, on the contrary, either pole is turn
CD away from the sun after the autumnal
equinox, the converse process takes place:
the higher parts of the continent are chilled
and the ensuing condensation of the vapor
m.tllc air liberatng its heat, raises the
temperature. and thus an interval of com.
paratlvcly warm weather or second sum-
mer follows. This simple explanation of
Indian summer first advanced by Admiral
Fitzroy, is corroborated by the fact that the
increase OF temperature attending it is the
greatest in the highest ATTITUDES of Ameri
ca, where it is described as sometimes "op-
prcssivc'-just where Of course the carth's
crust in October is undergoing the most
rapid refrigeration, where ice is forming
and consequently the heat of the condcnsa-
tlon ls most freely liberated from the lower
atmospheric strata The heat generated by
condensation is familiar to all who reflect on
their sensations when shower is being
formed in the clouds by this process on a
sultry day. Were it not for the compare
tive dryness of the air in the interior of tho
continent, or rather If il were moist enough
at this season, the cooling of the earth
would produce clouds and rain, instead of
the "dry fog" as Indian Summer is tech
nlcally called. The phenomenon in ques-
ton has. it would appear, been more the
theme of poets than of physicists But of
minor Importance in meteorological point
of view as it may seem, its further invcs-
tigation might furnish clue TO some prob
lens of our climate which arc yet unsoycd.
The fine particles of dust which often fall
on vessels in the open Atlantic, near the
Cape Verde Islands, when subjected to the
microscope, have proved tallics on the
winds, serving to fix the dirccrion of the
"trade winds" from tho African coast, and
thus clear up one of the questions of ocean
mcteorology. Many no less striking exam
pies of seemingly unimportant phenomena
leading to important discoveries abound in
the history of science.