TABLE III. Extracted from the Journal of L i e u t . H o o d , R. N. The above diurnal variations were obtained by one of Kater’s Compasses,
which may be read within a minute by the reflecting microscope. It was
placed on a shelf in a room of the Expedition-house, at Fort Enterprise, and
close to a parchment window, which admitted the air, by several holes. No
ferruginous matter was near enough to affect it; but it was twice accidentally
moved; and although the extent of the error thereby occasioned, was ascertained
by comparison with Mr. Franklin’s observations, and those of the preceding
days,-yet their connexion is not to be fully depended on, so as to derive
from them the monthly variations. However, the intermediate periods
will serve to show the variation for particular days, and also the amount of
aberration caused “by the Aurora.
A diurnal variation evidently exists; the maximum of which is at 9h. a.m.
and the minimum, at 3 or 4h. p.m. The irregularities of the needle may be attributed
to the Aurora; because the appearance of that meteor has been so
much more frequent here than at Cumberland-House, where the needle was
not often disturbed.
Some other opinions were inserted in this part of Mr. Hood’s journal; but
as they are detailed more at length in his preceding remarks on the Aurora
Borealis at Fort Enterprise, they are omitted here.
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