The thermometer
was at this time-18 deg., the barometer 30.14 inches, and the weather
nearly calm, and quite clear and serene.
About one o'clock on the morning of the 23d February, the Aurora
appeared over the hills in a south direction, presenting a brilliant
mass of light. The rolling motion of the light laterally was very
striking, as well as the increase of its intensity thus occasioned. The
light occupied horizontally about a point of the compass, and extended
in height scarcely a degree above the land, which seemed, however, to
conceal from us a part of the phenomenon. It was always evident enough
that the most attenuated light of the Aurora sensibly dimmed the stars,
like a thin veil drawn over them. We frequently listened for any sound
proceeding from this phenomenon, but never heard any. Our variation
needles, which were extremely light, suspended in the most delicate
manner, and, from the weak directive energy, susceptible of being acted
upon by a very slight disturbing force, were never, in a single
instance, sensibly affected by the Aurora, which could scarcely fail to
have been observed at some time or other, had any such disturbance taken
place, the needles being visited every hour for several months, and
oftener when anything occurred to make it desirable.
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