'--With
respect to the discordance of dips of the dipping-needles, which for
years past had been a source of great trouble and puzzle, the Report
states that 'The dipping-needles are still a source of anxiety. The
form which their anomalies appear to take is that of a special or
peculiar value of the dip given by each separate needle. With one of
the 9-inch needles, the result always differs about a quarter of a
degree from that of the others. I can see nothing in its mechanical
construction to explain this.--Reference is made to the spontaneous
currents through the wires of telegraph companies, which are
frequently violent and always occur at the times of magnetic storms,
and the Report continues 'It may be worth considering whether it would
ever be desirable to establish in two directions at right angles to
each other (for instance, along the Brighton Railway and along the
North Kent Railway) wires which would photographically register in the
Royal Observatory the currents that pass in these directions,
exhibiting their indications by photographic curves in close
juxtaposition with the registers of the magnetic elements.'--In
connection with the Reduction of the Greenwich Lunar Observations from
1831 to 1851, the Report states that 'The comparison of Hansen's Lunar
Tables with the Greenwich Observations, which at the last Visitation
had been completed for one year only, has now been finished for the
twelve years 1847 to 1858.
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