change to have been received from an Aurora; because the same weather,
preceding and following it, did not affect the needle in the day, when the
increased warmth of the air was more favourable to the production of
electricity in other quarters, and also to its passage. On the 24th of May,
between lOh. and 12h. p. m„ the needle was attracted to the conductor, and
repelled 25°*. The next morning, Mr. Franklin found the needle of the
transit instrument (which was then in the meridian) affected 20. The brightness
of the twilight prevented us from seeing the Aurora, and I therefore
discontinued my observations.
That electricity was the cause of the motions which I have described does
not admit of a doubt. But whether the electricity was received from, or summoned
into action by, the Aurora, my readers will determine for themselves,
being in possession of the facts upon which I have myself founded my opinion.
appearances o f t h e aurora a t fo r t e n t e r pr ise .
Extracted from the Journal of L ie u t e n a n t H o od, R.N.
1821, January 10th, at 8h. p. m., an arched Aurora N.N.W. to N.N-E. At
llh- p. m. a double arch,much broken, but not bright, from N.W. to S.E.
11th. At midnight, faint Aurora from west to east.
14th. At midnight, five arches of Aurora from N.W. to S.E.: a large
cor1o5ntah .b orAeat lims.idnight, an arched Aurora from N.W. to S.E.; beams very
bright; colours, violet below, pea-green above. Their motion did not appear
to be general in any direction, but proceeding from particular points towards
the S.E. and N.W. at the same time: weather dear.
21st. At midnight, a double arch; extremities N.W. to S.E. centre S.W.
12°high. At lh. a. m., a large body issued from N.W. and covered the sky
with wreaths and flashes: colour as usual.
22d. At 9h. p. m., faint arch from N. b. W. to E.
23d. At 9h. p. m., a double arch, N.W. to S.E., centre S. W. 60° high.
The thermometer was then 20°, and at 3h. p. m. it had been 58°.
January 24th. At 9h. p.m., a bright double arch from W. to S.S.E.: rapid
motion of beams.
25th. At 9h. p.m., five parallel arches, the centre one from N.W. to S.E.
The northernmost arch was the brightest, the rest faint.
27th. At 8h. p.m., faint arch from N.W. to E.S.E., centre N.N.E.
28th. At 9h. p.m., faint arch from N.N.W. to E. b. S .; at llh. it
advanced to the zenith, and the beams were distinguishable ; extremities
N.W. and S.E.
30th. At 2h. a. m., an arch N.W. to S.E. composed of many wreaths
of beams ; bright, with rapid motion; colour as usual. At midnight, Aurora
similar to that of last night: general motion of wreaths S.E.
February 1st. At 2h. a. m., an Aurora similar to that of last night. At
midnight, an Aurora similar to that of last night.
3d. At lh. a. m., an arch N.W. and S.E., which passed S.W., and was
followed by another at 2h. a. m.: at midnight, Aurora much broken and scattered
over the sky.
' 5th. At midnight, several wreaths of beams, some of them Coronse Boreales,
occupying a large space from N.W. to S.E.
6th. At llh. p. m., a faint arch N.W. to S.E.
7th. At midnight, Aurora similar to that of last night.
8th. At midnight, a bright arch N.W. and S.E., centre S.W. 65° high;
rapid motion of beams: at 2h. a. m., it passed to S.W.
9th. At llh. p. m., Aurora across the zenith, N.W. and S.E.; at 2h. a. m.,
it passed to the southward.
10th. At 7h. p.m., appearance of Aurora N.W.
11th. At 3h. p. m., an arch-of clouds exactly resembling the Aurora, from
W.N.W. to E.S.E., they were, however, driven away by the wind.
12th. At llh. p. m., two arches N.W. to S.E. passing quickly S.W.
14th. At midnight, arched Aurora, W.N.W. and E.S.E.: some exceedingly
bright flashes, which, as usual, appeared and disappeared without
changing their positions.
15th. At lOh. p. m., faint arch, W.N.W. and E.S.E.
19th. At 9h. p. m., an arched Aurora, N.N.W. and E.S.E.; at lh. a. m.,
some segments of arches in the zenith and to the southward; slight interior
motion: colour ordinary.