There is a well-marked annual periodical change in the
position of the Transit Circle, the southerly movement of the eastern
pivot having its minimum value in September, and its maximum in March,
the extreme range being about 14 seconds; and there is a similar
change, but of smaller amount, in the position of the Collimator. I
cannot conjecture any cause for these changes, except in the motion of
the ground. There is also a well-marked connection between the state
of level of the axis and the temperature. The eastern pivot always
rises when the temperature rises, the extreme range being about 6
seconds. I cannot offer any explanation of this.'--Under the head of
Extraneous Works the Report states that 'The British Government had
for some years past contributed by pecuniary grants to the preparation
of Prof. Hansen's Lunar Tables. In the last winter they undertook the
entire expense of printing a large impression of the Tables. The
reading of the proof-sheets (a very considerable labour) has been
effected entirely at the Observatory. I may take this opportunity of
stating that the use of these Tables has enabled me, as I think,
incontestably to fix the capture of Larissa to the date B.C.
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