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when D r. Ricliardson and Mr. Kendall we re wa tching for th e appearance of the meteor by
agreement, and udien it was seen by th e former actively sweeping across the heavens and
exhibiting prismatic colours, without any appearance of the kind being witnessed by th e
latte r, then only tw en ty miles distant from his companion. Captain P a rry also, in his T h ird
Voyage, describes the Au ro ra as being seen even between the hills and the ship anchored a t
P o rt Bowen.
D r. Ha iley and o th e r philosophers have supposed tliat th e coruscations o f the Aurora
proceed always in radii perpendicular to the surface of th e ea rth , in the direction of th e magnetic
meridian from th e poles toward the equator, and the former has ingeniously accounted
for th e ap p a ren t deviations occasionally witnessed on th e principles of perspective; but
this explanation is n o t quite satisfactory, as Captains P a rry , Pranklin, and ourselves, in
Kotzebue Sound, have seen these rays emanate from almost all p a rts o f the horizon, and
actually pass the zenith. A t the same time I am disposed to believe, from my own observation,
th a t the radii in g en e ra l tak e th e perpendicular direction above alluded to, probably on account
of th e less resistance th ey m ee t in the higher regions of the atmosphere than in such
as near th e surface of th e e a rth ; and this will p artly account for the appearance of the cone
formed a t th e zenith of the ships a t Melville P eninsula, described in Captain P a rry ’s Second
Voyage, pag e 146, and o f an o th e r very similar, witnessed by ourselves in Kotzebue Sound
on th e 26th August, 1827, on which occasion the rays shot up from all directions, and formed
over our zenith the perfec t appearance of a te n t stretched upon a number o f poles u nited a t
th e ir en d s; b u t even h ere th e rays could n o t have been qu ite parallel unless th e ir extremities
were infinitely high.
In Kotzebue Sound tb e Aurora was seldom visible before ten o’clock a t n ight, or after
two o’clock in th e morning. W e neve r hea rd an y noise, nor detected any disturbance of the
magne tic n e e d le : b u t here I must observe th a t K a te r’s compass was the only instrument
employed for this purpose, and th en on board th e ship only, th e exposed situation in wbich
we were anchored not adm ittin g o f an y establishment on shore, eitlier for this purpose or
for astronomical observations.
Mr. Collie, th e surgeon of the Blossom, whose a ttention to meteorological phenomena
was unwearied, has given an ingenious hypothesis on th e subject of the Aurora. After expre
ssin g his opinion th a t this meteor occurs in the region o f the thin and higher clouds of
th e ea rth’s atmosphere, he observes, th a t “ it is highly probable th a t th e two strata of atmospheric
fluid proceeding in opposite directions— the one from th e equinoctial toward the
polar regions, and the other in the reverse direction—are charged with opposite electricities,
and th a t th e y are in different degrees of temperature and o f humidity : th e u pper stratum,
flowing from the equa tor toward th e poles, bein g of a higher temperature and more charged
with vapour th an th e lower, proceeding from th e pole to th e equator. T h e y might thus be
charged with opposite electricities, which would communicate and neutralize eacJi otlier.”
“ T h e opposite temperatures would be reduced to tbeir mean, and under certain circumstances
these changes mig h t be attended with tb e evolution o f electrical light, and with the
condensation o f transpa rent vapour into thin clouds (stratus-cirrus, or cirro-stratus). As the
w a te ry particles of these clouds form, a certain degree of electric conductibility would be
established, by which this subtle fluid mig h t be propagated to short distances; but the gre ater
dryness o f the air, both above and below this region o f thin mist, would oppose an unconducting
barrier to its escape. As soon as one thin cloud, a thin stripe o f cirrus, or fleecy
portion of cirro-stratus or cirro-cumulus, became charged with electricity, it would occasion,
by the laws of electric phenomena, an ojiposite electrical state in th a t portion n ea rest i t ; and
these opposite electricities would instantly attra c t each other, fly together, burst forth in fire,
and become neutralized. I f tliere should be a plane in which such thin clouds are formed,
th e subversion and re -establishment o f th e balance o f electricity b ein g thus begun would be
rapidly propagated throughout the whole of this space, and produce th a t rapid, undulatory
motion which we observe in th e Aurora Borealis.”
In considering th e subject o f the Au ro ra Borealis, my a ttention was drawn to a fact
which does not appear to me to have been hitherto noticed. I allude to th e direction in
which the Aurora gene rally makes its first appearance, or, which is the same thing, the q u arte r
in which the arch formed by this meteor is usually seen. I t is remarkable, th a t in this country
th e Aurora has always been seen to the northward ; by th e expeditious whicli have wintered
in the ice it was almost always seen to the so u thward ; and by th e Blossom, in Kotzebue Sound,
250 miles to the southward of the ice, it was, as in England, always observed in a northern
direction. Coupling this with the relative positions o f the margins o f th e packed ice, and with
th e fact of the Aurora appe aring more brilliantly to vessels passing near the situation o f that
body, than by others en te red far within it, as would seem to be th e case from th e reports o f the
Greenland ships, and from my own observations a t Melville Island au d a t Kotzebue Sound,
i t does appear, a t first sight, th a t that region is most favourable to the production o f the meteor.
I do not, however, presume to offer any liypothesis on tlie s u b je c t; b u t having witnessed the
extraordinary change that takes place in the atmosphere, along the whole line of ice covering
the Polar Sea, I should be remiss if I omitted to direct the attention of the natura l philosopher
to the circumstance. T h e re is perhaps no p a rt o f the globe where the atmosphere undergoes
a gre a te r or more sudden cliange than over tliis line of tbe ice. A diminution of 10« or 15«
of temperature constantly occurs within the space of a few miles : the humid atmosphere over
the ocean may sometimes be seen laden with heavy clouds, whicli di.sperse as th ey arrive a t
this line of reduced temperature, and leave tlie region over the ice exposed to a bright
sunshine. In d e ed the extraordinary effect of this large body o f ice upon the atmospliere,
particularly when the sea is deep and the temperature of the ocean and its superstratum
of air high, as between S pitzbergen iuid Greenland, will scarcely be credited by persons
who have not witnessed it. Mr. Seoresby has given some extraordinary instances of this
in his Arctic Voyages; and to these I will add one o f many which fell un d er my own
observation. T h e ships of the first polar expedition were beset in the ice about nine
miles from the open sea. I t was blowing a hard gale upon the ice, and we could perceive
a ship ca rrying off under storm stay-sails only. T h e re was nothing between us an d the
ship to interc ept the gale, and y e t we were becalmed d u ring the whole of the day. The
atmosphere over the open sea was loaded with clouds {nimbi), while that over the ice enjoyed
a b rig h t sunshine throughout. T h e limits of these opposite states o f the atmosphere, by
seamen called the icc-Uink, were marked by a well-defined line, nearly perpendicular
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