ECLIPSES IN 1845, and TRANSIT OF MERCURY.

In the year 1845, there will be four eclipses; two of the Sun, and two of the Moon, and a Transit of Mercury. One of the solar eclipses will be partly visible in the United States, one of the lunar eclipses, and the transit of Mercury.

I. Tuesday, May 6th. An annular Eclipse of the Sun, partially visible in the United States.

Beginning of the general eclipse at 2h. 41.1m. M. [Mean Time at Washington,] in latitude 27° 13' North, and longitude 36° 55' West of Greenwich.

Beginning of the annular eclipse at 4h. 49.5m. M. in latitude 60° 43′ N. and longitude 103° 39′ W. of Greenwich.

End of the annular eclipse at 5h. 12.1m. M. in latitude 72° 39′ N., and longitude 136° 58' W. of Greenwich.

End of the general Eclipse at 7h. 20.6m. M. in latitude 48° 6' N., and longitude 101° 9' E. of Greenwich.

This eclipse will be visible throughout the greater part of Europe, the Northern part of Asia, the North Polar Sea, the North Atlantic Ocean, Greenland, Canada, New England, New York, New Jersey, Delaware, the North-eastern portion of Pennsylvania, and the North-eastern corner of Maryland. Being visible at the same time in Europe and America, it will be peculiarly valuable for determining the relative longitudes of places in the two continents.

The phases of the eclipse for all places in the United States may be determined with sufficient accuracy by means of the following tables.* The Sun's semi-diameter and horizontal parallax are the same as at conjunction, and may be taken from the following table:

ELEMENTS OF THE ECLIPSES OF THE SUN.

*The Almanac is indebted for the calculations of this Eclipse to Lieut. Charles H.

Davis, of the United States Navy.

Long.

Digits eclipsed on the Sun's northern limb for places in the United States, at the time

of the Sun's rising.

Long.

Long.

Angle of last point of contact from the northern point of the Sun's limb toward the East; and, in an inverting telescope, from the southern point toward the West.

Angle of the last point of contact from the vertex of the Sun's limb toward the East; and, in an inverting telescope, from the lowest point of the Sun's limb toward the West.

M. T. of Place at

Ending. rises. tion.

Phases of the eclipse for particular places.

[Note. For those places which are marked with an asterisk, the phases have been computed by a separate computation. The other phases are derived from the tables.]

Place.

Dura- greatest

vis. ecl.
on's

N. point

of

N. limb.

Greenw'h.
M. Time.

The following table of elements will serve to calculate the eclipse for any place in

the United States.

10 26 26 2

.2

.6 3296.9 1 0 14 31 29.1
.7
.82 0 29 2 58.2

II. Thursday, May 8. A Transit of Mercury, visible in the United States. The times of this transit may be found by the following tables: *

Calculated for the United States in Mean Greenwich Time.

Transit of Mercury calculated for particular places in Mean Time of place.

Hudson, Ohio,

54 2

23 21

University of Va.,

5 28

34 51

Montreal,

Washington,