... The number of
observations to the end of 1851 (after which time the parallax will be
corrected in the current reductions) is about 2560. An expense
approaching to _L400_ might be incurred in their reduction.'
Subsequently I made application to the Admiralty, and the _L400_ was
granted on Dec. 12th.--In the Report to the Visitors it is stated that
with regard to the Transit Circle, changes are under contemplation in
its reflection-apparatus: one of these changes relates to the material
of the trough. 'Several years ago, when I was at Hamburgh, my revered
friend Prof. Schumacher exhibited to me the pacifying effect of a
copper dish whose surface had been previously amalgamated with
quicksilver.......The Rev. Charles Pritchard has lately given much
attention to this curious property of the metals, and has brought the
practical operation of amalgamation to great perfection. Still it is
not without difficulty, on account of a singular crystallization of
the amalgam.'--With regard to the Chronograph, the Report states: 'The
Barrel Apparatus for the American method of observing transits is not
yet brought into use.... I have, however, brought it to such a state
that I am beginning to try whether the Barrel moves with sufficient
uniformity to be itself used as the Transit Clock.
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