The evening telegraph. [volume] (Philadelphia [Pa.]) 1864-1918, 1869-05-24
THE JUNE MAGAZINES.
'sUARPER,S.o


to,the morning twilight whence il has received
the name of aurora. In the northern hemisphere
IT is usually termed aurora borealis, because 1t
ls chiefly seen in the north. similar pheno-
Inenon is also seen in the southern hemisphere,
where 1t is called Aurora Australis. Eacn OF
them may, with greater. propriety De caIGa cIa
Aurora POlaris, or Polar Light. Ihey GAn.piS GAiS
an endless variety of appearances. In Ine OIlVou
States an aurora is uniformly preceded Oy u hiiIy
OF saty appearance of the sky, particularly IN
the neighborhood of the northern horiHon.
When the auroral display commences, this hazy
nortion Of the sky assumes the form of n dark
bank or segment of a circle in the north, rising
ordinarily to the height OF IRON hVe TO ten
degrees This dark segment is not n cloud Tor
the stars are seen through ii as through smoky
atmosphere, with little dmnutiOn OF brillancy
This dark bank is simply dense haze, and it
appears darker from the luminous arc which
rests upon il. In high northern ATTITUDES, when
the aurora covers the entire heavens, the whole
sky seems filled with a dense haze; and in still
higher latitudes, where the aurora is sometimes
seen in the south this dark segment is observed
resting on the southern horizon and bOrdcrcd 10y
the auroral light.
"Auroras are sometimes observed simulta-
neousy over large portions of the globe. The
aurora OF August 2S 1859, was seen throughout
more than l40 degrees of longitude, from East
ern Europe to California, and from Jamaica on
the south to an unknown distance in British
America on the north. The aurora of Septem-
Der 2, 1859, was seen at the Sandwich Islands; 1t
was seen throughout the whole OF North America
and Europe; and the disturbance OF the mag
netic needle indicated its presence throughout
al Northern ASIA although the sky was over
cast so that at many places it could not be seea.
An abrOra was seen at the same time in South
America and New Holland The auroras of Sep
tember %, 1874, and November H., lS4S, were
almost equally extensive.
"The height of a large number OF auroras has
been computed, and the average result for the
upper limit of the streamers is $50 miles From
multitude of observations il IS concluded that
the aurora seldom appears Mt an elevation less
than about 45 miles above the earths surface,
and that it'frequently extends upward to an elc-
walton OF 500 miles. Auroral arches having
weu-defned border are generally less than 100
miles in height.
"Auroras are very uneQually distributed
the earth's surface. They occur most frequently
in the higher latitudes, and are almost unknown
within the tropics. At Havana, in latitude %
degrees, but six aurOras have been recorded
within hundred years. and south of Havana
aurOras are still more untrequent. As we travel
nOrthward from Cuba aurOras increase in fire.
uuency and brilliancy; they rise higher in the
heavens. and OtJener ascend To the zenith. Near
the parallel of 40 degrees we find on an average
only ten aurOras annually. Near the parallel of
~ degrees the average number is twenty an
nually near 10 degrees the number is forty, and
near the parallel of 80 degrees il amounts 10
eighty annually. Between this point and the
parallel of 62 degrees aurOras, during the winter.
are seen almost every night. They appear high
in the heavens, and rs often to the south as the
north. In regions further north they are seldom
seen except in the south, and from this point
they diminish in frequency and brllliancy as we
advance towards the pole. Beyond latitude %
degrees the average number OF auroras is reduced
10 forty annually. Beyond latitude 67 degrees
ii is reduced to twenty; and near latitude Is de-
grees il is reduced to tenannualv.
"Auroral exhibitions take place in the upper
regions of the atmosphere. since they partake of
The earth's rotation. All the celestial bodies
have an apparent motion from east to west,
arising from the rotation of the earth but bodies
belonging to the earth. including the atmosphere
and the clouds which float in it. partalle of the
earths rotation, so that their relative position is
not affected by ii. The same is true of aurOral
exhibitions. Whenever an auroral corona is
formed, it maintains scu,iblv the same position
il the heavens during the whole period of its
continuance although the stars meanwhile re-
Yolye at the rate of fifteen degrees per hour.
''Ihe grOsser part of the earth atmosphere is
Limited TO a moderate distance from the EARTH
At the height of a little over four miles. the
density OF the air is only One-half what it is at
the Carths surface, At The height OF fifty miles
the atmosphere is well-ngh inappreciablc in its
effect upon twilight. The phenomena of lunar
ecllpses indicate an apprcciable atmosphere at
the height Of 66 miles. The phenomena OF
shooting stars indicate atmosphere at the
height OF 200 or 800 miles, while the aurora in
dlCates that the atmosphere does not entirely
cease at the height of 500 miles. AurOral eXhi-
blnons take place therefore, in an atmosphere
OF extreme rarity: so rare indeed that if, in eX-
perments with an air-pump, we could exhaust
the air as completely we should say that we had
obtained perfect vacuum.
The aurOral beams are simply spaces which
are iilUnined by the flow of electricity through
the upper regions of the atmosphere. During
the aurOras of lS59{these beams were nearly 800
miles in length, and their lower eXtremities were
elevated about 45 miles above the earths surface.
Their tops inclined towards the south, about II
degrees in the neighbOrhood of New York, this
being the position which the dipping-needle
there assumes"
From Mr.. w. o. Stoddar's paper on Pawn
brokers and Loan Offices" we make these
extracts
During the summer months the business of
the paWnbrokers though good, is not by any
means pressing. The labOring classes are then,
for the most part, well and prohtably employed,
and If IL were not for rum, idleness and real
inistortune-such as sickness-there would be
comparatively little for my uncle to do. As
winter comes on, however, one source of employ
ment after another is closed, expenses increase.
while curiously enough, miscellaneous crowds
with slender resources flock from the country
In TINS city the stream of peOpeftrom OVeT-sea
furnishes never-tailing supply OF business to
the paWnbrOker, and these people seem TO hold
OF wonderfully until the approach of cold
weather. Then, however, his shelves begin to
I'll up. All the carly summer they grew
thinner, as one pledge after another was redeemed
by those who once more found a remuneratiVe
demand for their time and labor: but now even
The rapidly accruing forfeits' do not make
room enough for the fresh offerings. Bits of
ewelrY; furniture; clothing of all kinds relics of
better days; odd mementOes of far away lands
beyond the sea; articles of domestic use beyond
mention-or unmentionabe-all is fish that
comes 10 his net, if only it have market value
or, in his opinion a reasonable prospect of ulti.
mate redemption. Hardly article is offered
uDon which the pawnbToker is not begged tC
advance more but his trade hardens him, and
he invariably decides in accordance with wha