Without having
absolutely decided on a site, I may suggest that I should wish to
erect a brick building, about 50 feet by 20, consisting of two very
low stories (or rather of one story with a gallery running round its
walls), so low that books can be moved by hand without necessity for a
ladder.--In the month of December, 1877, the azimuthal error of the
Transit Circle had increased to 10". A skilful workman, instructed by
Mr Simms, easily reduced the error to about 2".5 (which would leave
its mean error nearly 0), the western Y being moved to the north so
far as to reduce the reading of the transit micrometer, when pointed
to the south, from 35r.500 to 35r.000. The level error was not
sensibly affected.--The Sidereal Standard Clock preserves a rate
approaching to perfection, so long as it is left without disturbance
of the galvanic-contact springs (touched by its pendulum), which
transmit signals at every second of time to sympathetic clocks and the
chronograph. A readjustment of these springs usually disturbs the
rate.--To facilitate the observations of stars, a new working
catalogue has been prepared, in which are included all stars down to
the third magnitude, stars down to the fifth magnitude which have not
been observed in the last two catalogues, and a list of 258 stars of
about the sixth magnitude of which the places are required for the
United States Coast Survey.
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