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APPENDIX. 
when Dr. Richardson and Mr. Kendall were watching for the appearance of the meteor by- 
agreement, and when it was seen by the former actively sweeping across the heavens and 
exhibiting prismatic colours, without any appearance of the kind being witnessed by the 
latter, then only twenty miles distant from his companion. Captain Parry also, in his Third 
Voyage, describes the Aurora as being seen even between the hills and the ship anchored at 
Port Bowen. 
Dr. Halley and other philosophers have supposed that the coruscations of the Aurora 
proceed always in radii perpendicular to the surface of the earth, in the direction of the mag- 
netic meridian from the poles toward the equator, and the former has ingeniously accounted 
for the apparent deviations occasionally witnessed on the principles of perspective; but 
this explanation is not quite satisfactory, as Captains Parry, Franklin, and ourselves, in 
Kotzebue Sound, have seen these rays emanate from almost all parts of the horizon, and 
actually pass the zenith. At the same time I am disposed to believe, from my own observation, 
that the radii in general take the perpendicular direction above alluded to, probably on ac- 
count of the less resistance they meet in the higher regions of the atmo.sphere than in such 
as near the surface of the earth; and this will partly account for the appearance of the cone 
formed at the zenith of the ships at Melville Peninsula, described in Captain Parry’s Second 
Voyage, page 146, and of another very similar, witnessed by ourselves in Kotzebue Sound 
on the 26th August, 1827, on which occasion the rays shot up from all direction.s, and formed 
over our zenith the perfect appearance of a tent stretched upon a number of poles united at 
their ends; but even here the rays could not have been quite parallel unless their extremities 
were infinitely high. 
In Kotzebue Sound the Aurora was seldom visible before ten o’clock at night, or after 
two o’clock in the morning. We never heard any noise, nor detected any disturbance of the 
magnetic needle : but here I must observe that Kater’s compass was the only instrument 
employed for this purpose, and then on board the ship only, the exposed situation in which 
we were anchored not admitting of any establishment on shore, either for this purpose or 
for astronomical observations. 
Mr. Collie, the surgeon of the Blossom, whose attention to meteorological phenomena 
was unwearied, has given an ingenious hypothesis on the subject of the Aurora. After ex- 
pressing his opinion that this meteor occurs in the region of the thin and higher clouds of 
the earth’s atmosphere, he observes, that “ it is highly probable that the two strata of at- 
mospheric fluid proceeding in opposite directions — the one from the equinoctial toward the 
polar regions, and the other in the reverse direction — are charged with opposite electricities, 
and that they are in different degrees of temperature and of humidity : the upper stratum, 
flowing from the equator toward the poles, being of a higher temperature and more charged 
with vapour than the lower, proceeding from the pole to the equator. They might thus be 
charged with opposite electricities, which would communicate and neutralize each other.” 
“ The opposite temperatures would be reduced to their mean, and under certain circum- 
stances these changes might be attended with the evolution of electrical light, and with the 
condensation of transparent vapour into thin clouds (stratus-cirrus, or cirro-stratus). As the 
watery particles of these clouds form, a certain degree of electric conductibility would be 
