... The chemical treatment of the paper is now so well
understood by the Assistants that a failure is almost unknown. And,
generally speaking, the photographs are most beautiful, and give
conceptions of the continual disturbances in terrestrial magnetism
which it would be impossible to acquire from eye-observation.'
--Amongst the General Remarks of the Report it is stated
that 'There are two points which have distinctly engaged my
attention. The first of these is, the introduction of the American
method of observing transits, by completing a galvanic circuit by
means of a touch of the finger at the instant of appulse of the
transiting body to the wire of the instrument, which circuit will then
animate a magnet that will make an impression upon a moving
paper. After careful consideration of this method, I am inclined to
believe that, in Prof. Mitchell's form, it does possess the advantages
which have been ascribed to it, and that it may possess peculiar
advantages in this Observatory, where the time-connection of transits
made with two different instruments (the Transit and the Altazimuth)
is of the highest importance.... The second point is, the connection
of the Observatory with the galvanic telegraph of the South Eastern
Railway, and with other lines of galvanic wire with which that
telegraph communicates.
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