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phenomenon, correct the local mean time by adding the difference between standard and local time if the place is west of the standard meridian, and subtracting if east. The same rules apply. to the fourth and sixth columns, which give the local mean times of rising and setting for the meridian of Greenwich. They are roughly computed for Lat. 40°, with the noon Declination and time of meridian transit, and are intended as only a rough guide. They may be in error by a minute or two for the given latitude, and for latitudes differing much from 40° they may be several

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ECLIPSES OF JUPITER'S SATELLITES, P. S. T.

(Phenomena near right hand limb of planet as seen in an inverting telescope.)

III, D, May 1.

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ΙΟ 8 P. M.

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6 31 P. M.

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The Sun is too near the star, and the star too near the horizon, for convenient observation of minima.

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ECLIPSES OF JUPITER'S SATELLITES, P. S. T. (Phenomena near right-hand limb of planet as seen in an inverting telescope.)

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The Sun is too near the star, and the star too near the horizon,

for convenient observation of minima.

EPHEMERIS FOR PHYSICAL OBSERVATIONS OF THE MOON FOR CERTAIN DATES

BETWEEN 1890 AND 1896.

COMMUNICATED BY DR. A. MARTH, F. R. A. S.

NOTE. Dr. MARTH has been so good as to compute the following table, corresponding to times at which certain negatives of the Moon have been taken at Mt. Hamilton with the thirty-sixinch refractor. The times usually correspond to focal negatives presented by the Lick Observatory to the Observatory of Prague. The last entry refers to Map No. 1 of the Observatory Atlas of the Moon, published by the Lick Observatory. It is Dr. MARTH'S intention to continue these computations.

E. S. H.

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The topocentric libration gives the selenographical longitude and latitude of the point on the Moon's surface which occupies the center of the disc, as seen from the Lick Observatory. P. denotes the position-angle of the Moon's axis, reckoned from the apparent circle of declination.*

REVIEW OF SOLAR OBSERVATIONS, 1895 (AUGUSTDECEMBER) AND 1896.

BY DAVID E. HADDEN.

The following solar observations are a continuation of those communicated to the Society for the years 1891 to June, 1895, and published in Vol. VII., No. 45, of the Publications.

The instrumental outfit used has remained the same, viz.: a three-inch equatorially mounted telescope, and a grating spectroscope of 14,438 lines to the inch.

During the year 1896 the appearance and approximate position and size of each sun-spot group and facula have been sketched daily on sheets of paper containing a three-inch ruled circle, divided into quadrants, the east and west line being set parallel with the Sun's apparent motion, by allowing the limb of Sun's image to move tangent to the horizontal spider-line in the eyepiece; the observations are afterward properly corrected for position angle of the Sun's axis and inclination to the ecliptic. By this means an approximate position of the latitude and longitude is obtained.

Complete observations and detailed descriptions of the results have been published in the Monthly Review of the Iowa Weather and Crop Service.

The following tables exhibit the summaries of these observations:

RESUMÉ OF SOLAR OBSERVATIONS.

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