ROYAL OBSERVATORY, GREENWICH.

OBSERVATIONS OF DRACONIS

WITH THE ZENITH TUBE,

AND

REDUCTION OF THE OBSERVATIONS.

1844.

Before the observations of February 7, the collar which forms the upper bearing of the tube was oiled.

Feb. 7 and Feb. 26. Something appears to be wrong in these observations.

The correction -1"-374, to reduce the readings of the Grand Micrometer for the bisections of the star, face West, with wire V*, to the readings for wire V, has been applied in forming the Star's Apparent Zenith Distance uncorrected, face West.

Feb. 28. This result proving bad, the plumb-line was examined, but no defect was perceived.

March 5. Eye-piece East. The second reading of the lower plumb-line microscope was set down 100.746.

March 17d. 23h. The plumb-line was raised and cleared of cobwebs; the speculum was taken out and cleaned, and every

part of the instrument was minutely examined.