The Grand Haven news. [volume] (Grand Haven, Mich.) 1858-18??, 1860-03-28
Complete Description Of the Aurora
Borealis and Aurora Austraiis.

lains mn article on the aurora. by Prof.
Joseph Lowering, of Havard University,
which by its numerous references, displays
laborious research and thorough investi-
cation on the subject. Among the nu-
merous facts stated, the most interesting
one is that "the crown OCCURS around
that point Of the sky TO which perfect
ly free magnetized needle points," After
verv elaborate discussion on the period
icity of the aurora, Professor Lowering
comes to the following conclusions -
"There is secular periodicity, consisting
of 20 years or more of abundant exhibit
tions, separated by intervals, equally long
or longer, when tho phenomenon, if not
wholly wanting, is unaccompanied by any
of its moro striking characteristics" 1t
is observed quite as often in summer rs
in winter. ain regard to the diurnal pc
riodicity, the general fact is observable,
that, although grand auroras, MS that for
example of August 2s, 1859, may last
through the whole night, generally the
aurora dies out before midnight; and even
the best displays usually attain their
maxium before 10 or ii O'clock" 1t is
seen most frequently in the neighborhood
of tho magnetic pole. Scoresby says
that in Iceland the aurora may be seen al
most every clear night in winter. Frank
lin had 124 examples of it in six months
in the Arctic Sea-" Careful and numer-
ourous experiments have been made to
determine by the property of polarization
whether the light eminates directly from
the aurora or is reflected. The point is
not absolutely settled, but it is highly
probable that the light is net reflected
Professor Coverings discussion of the
question, whether this phenomenon is ac-
companied by any sound, affords a very
striking proof of the uncertainty of hu-
man testimony resulting from the gene
raj carelessness of observation. The i'm
preston left upon the mind by the whole
mass of conflicting testimony is, that it is
not very probable that any noise does ac-
company the aurora. 1t is the opinion Of
Arago that the methods adopted to as
certain the hight of the aurora above the
earth are not 10 be relied on, and that this
point is still wholly undetermined. In re-
gard 10 the character of the light the fol-
lowing quotation is made from Singers
Elements of Electricity: "When elec-
tricity passes through rarcfied air, il ex-
hibits a diffused. luminous stream, which
has all the characteristic appearance of
the northern lights. There is the same
variety of color and intensity, the same
undulating motion and occasional corrus-
cations; the streamers exhibit the same
of character, at one moment
divided in ramificatiops and at another
beaming forth in one body of light, or
passing in distinct broad flashes; and
when The rarefaction is considerable, vari-
Gus parts OF the stream assume that pc
culiar glowing color which occasionally
appears in the atmosphere, and is regard
ed by the uniformed observer with as
tonishment and fear"
The article closes with brief notice
of some of the explanations that have
been offered. Some may be passed over
lightly; such as that of the ex-king of
Sweden, who imagined the light was
ground out by the friction of the earth
on its great axle. Franklin modestly sug-
gested the following: "May not, then,
the great quantity of electricity brought
into the polar regions, by the clouds,
which arc condensed there, and fall in
snow, which electricity would enter the
earth, but could not penetrate the ice,
may it not | say las bottle overcharged)
break that low atmosphere, and run along
in the vacuum over the air towards the
diverging as the degrees of lon
gitude enlarge, strongly visible where den-
sest, and becoming less visible as il more
divergcs; till it finds passage to the
earth in more temperate climates, or is
mingled with the upper airl If such an
operation of nature were really performed,
would it not give all the appearance Of an
aurora borealis 2" Marian and the late
Professor d. Olmstead, of Yale College,
both believed the origin of the aurora to
be in space beyond the boundaries of our
earth and its atmosphere, or some nebu-
lous matter which the earth occasionally
meets in its fight through space. 1t is GER
tain, however, that il partakes not only OF
the motion of the earth about the sun,
but also of the rotary motion about Its
axis.
The conclusion of the whole matter IS,
that the aurora borealis is so swift and
changing in its motions, so distant in its
nosition. and so subtle in its nature, that
Il battles investigation, and remains, more
than anything else which can be so plain
" seen, largely enveloped in mystery
We respectfully suggest to the numerous
gentlemen who are concocting theories
in regard to this phenomenon, to procure
Professor Loverings article in order to
avail themselves of the numerous facts
which he has collected. The real masters
of science almost always exhibit this Ia
Dor in collecting facts, combined with a
in offering their own theories IN
explanation Of them.
[Scientifc American.