--The
correction for level error in the Transit Circle having become
inconveniently large, a sheet of very thin paper, 1/270 inch in
thickness, was placed under the eastern Y, which was raised from its
bed for the purpose. The mean annual value of the level-error appears
to be now sensibly zero.--As the siege and war operations in Paris
seriously interfered with the observations of small planets made at
the Paris Observatory, observations of them were continued at
Greenwich throughout each entire lunation during the investment of the
city.--The new Water-Telescope has been got into working order, and
performs most satisfactorily. Observations of gamma Draconis have been
made with it, when the star passed between 20h and 17h, with some
observations for adjustment at a still more advanced time. As the
astronomical latitude of the place of observation is not known, the
bearing of these observations on the question of aberration cannot be
certainly pronounced until the autumn observations shall have been
made; but supposing the geodetic latitude to be accordant with the
astronomical latitude, the result for aberration appears to be
sensibly the same as with ordinary telescopes.--Several years since, I
prepared a barometer, by which the barometric fluctuations were
enlarged, for the information of the public; its indications are
exhibited on the wall, near to the entrance gate of the Observatory.
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