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EVE'S EVENING SONG TO THE INFANT CAIN.

My Cain, my little one, on thee

Thy sinful mother's tears shall fall,
While thou, asleep upon her knee,
Heedest not nature's thickening pall.

O! baby, 'neath the brightest trees,
It had been thine to lie to rest,
The while I watch'd the summer breeze
Play with the leaflets o'er thy breast.

O, hush! Each grief that troubleth thee,
Each tear that wets thy infant face,
Swells my sad heart to agony:

I, I have ruin'd all thy race.

May God, whose love surmounts my crime,
Send an angelic band from heaven,

To watch thee at this lonely time,

And tell to me my guilt forgiven.

So though thy mother cannot keep

From spirits fierce, or beasts of earth,
Yet may'st thou, infant, calmly sleep :

HE sees, who gave all nature birth.

But O! how can I think and live,

I drew thee with me in my fall!
That innocence I cannot give,

I lost for thee, for me, for all.

Eden, with all its heavenly song,
Its holiness, as God's complete,
To thee, my babe, might now belong:
Thy mother tore thee from that seat!

FRANCES LUCY.

CELESTIAL OBJECTS.

MARCH, 1854.

ASTEROIDS. We proceed to explain the table of constants for the orbits given in the last Number :

The column headed a contains, as has been stated, the semi-axis

2

=

major of the orbits, that of the Earth's orbit being taken as unity. Since the semi-axis major is half the sum of the planet's greatest and least distances from the Sun (aphelion and perihelion distances), a is usually called the mean distance. Divide 1,296,000, the seconds in 360°, by the time of the planet's revolution, expressed in mean solar days, the quotient is the mean daily angular motion: this quotient, multiplied by the time elapsed since the planet was last in perihelion, produces the mean anomaly. The value of this quantity for each planet, on the 1st day of January, 1854, at Greenwich mean noon, is given in the second column, headed M. The mean anomaly for any time subsequent is easily found by adding the mean angular motion in the interval; for any time before the epoch, of course the mean angular motion must be subtracted from the value of M at the epoch. From the mean anomaly at any time, by the aid of the numbers given in the two last columns, may be deduced the distance of the planet from the Sun, called the radius vector, and the angle which this distance makes with the perihelion distance, called the true anomaly. The angle under ø serves to determine the eccentricity of the orbit: it is the angle which a radius vector drawn to one extremity of the minor axis makes with that axis.

A diagram may serve

B

E

A

to make these matters clearer. The ellipse represents the orbit of the planet; S, the Sun, in one focus; AB is the axis major; consequently A C-CB-SD-a, the mean distance; AS is the perihelion, and BS the aphelion distance; the angle SD C, is what has been represented by; its sine, or SC divided by SD, is called the eccentricity, and is usually denoted by e. The time at which the planet is in A, or nearest the Sun, is called the perihelion passage: at any other time, suppose the planet is at P, the distance SP is the radius vector (r), and the angle ASP the true anomaly (0). Our space forbids the explanation of the other three columns, 7, 8, and i, in this Number. MERCURY will be in perihelion at 8h. on the morning of the 3d: distance from the Sun 29,330,000 miles. On the 27th, at 7h. in the morning, he will be in perigee distance from the Earth, 56,790,000 miles. As usually happens, the time of the planet's inferior conjunction with the Sun does not coincide with that of his nearest approach to the Earth: this month it will occur three days ten hours earlier; or, in more popular language, Mercury will pass the Sun, a little northward of his disc, from the eastern to the

western side, on the 23d, at 9h. afternoon. On the 7th, at 1h. morn., the planet will have reached his greatest angular distance from the Sun, 18° eastward, on which day he will set 1h. 49m. later than the Sun. On the 13th he will be in that part of his orbit highest above the plane of the ecliptic, on the north side. The right ascension increases till the 13th, at 10h. afternoon, when it is equal to Oh. 24m. 36s.; afterwards it diminishes: in other words, his apparent motion among the fixed stars, previous to that time, is eastward, subsequently westward. His form on the 9th is that of the Moon when six days old. It may be thought interesting to contrast his appearance with that of Venus on the same day: the annexed representations may be useful for this purpose. The outlines and relative magnitudes are correct; not so the relative positions: Mercury will on that day be east of the Sun, Venus west.

VENUS passed to the eastern side of the Sun on the last day of February. Toward the end of the present month she will, therefore, outshine Jupiter as morning star. The drawing has been made for the 9th, when her apparent diameter will be very little less than its maximum value: it will be nearly one-third less on the 1st of April: her distance will then have increased to thirty-nine millions of miles. She will appear to move westward among the fixed stars, until, on the 19th, at 11h. morn., she reaches a point 5° southeastward of a Aquarii, at which time her right ascension will be 22h. 5m. 23s. after this her apparent motion will be direct. On the 4th, a little after midnight, she will be furthest from the plane of the ecliptic. On the 25th she will not be far from the Moon.

MARS is now most favourably situate for telescopic examination,

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being visible almost the entire night. She is moving westward toward Regulus, the brightest star in Leo. On the morning of the 13th he will be occulted by the Moon's southern limb. This phenomenon will be witnessed at Greenwich from 3h. 11m. to 3h. 37m. The apparent diameter, toward the middle of the month, will be about one-fourth that of Venus, and rather less than one and a half times that of Mercury. His northern declination will have increased to 15° 6' on the 31st: after this time it will diminish. His distance from us increases ten millions of miles during the month.

JUPITER is five hundred and forty-nine millions of miles distant from us on the 1st of March, and five hundred and seven on the 1st of April. His apparent diameter, which at the beginning of the month is little more than half that of Venus, will be only about onesixth less than hers at the end. On the morning of the 23d he will be near the Moon. The more remarkable phenomena of the satellites, visible to us, are:

20th. 4h. 57m., egress of second from planet's disc.

234, 4h. 48m., re-appearance of first from behind the planet. 27th, 4h. 48m., second enters on disc.

SATURN will be forty-three millions of miles more distant from us on April 1st than on March 1st. He will be close to the Moon on the morning of the 5th. The nearest approach of the centres will take place at 4h., when these bodies are below our horizon: to many other inhabitants of the northern hemisphere, in latitudes higher than 46°, the planet will be occulted. The diameter of the sphere, on the 16th, will be 16", a very little less than the minor axis of the ring: the major axis will be 39.

URANUS may still be seen in the early part of the evening. His distance will increase thirty-five millions of miles during the month. NEPTUNE will be at his greatest distance from the Earth, two thousand nine hundred and fifty millions of miles, on the 5th, at 1h. morning. Seen from that distance, the diameter of the Earth would subtend an angle of a little more than half a second, which is twelve times less than the diameter of Mercury will appear to us on that day.

Spring quarter commences on the 20th, at 10h. 20m. in the afternoon.

"The bud is in the bough, and the leaf is in the bud,

And earth's beginning now in her veins to feel the blood,
Which warm'd by summer sun, in the' alembic of the vine,
From her founts will overrun in a ruddy gush of wine.

"The perfume and the bloom that shall decorate the flower
Are quickening in the gloom of their subterranean bower;
And the juices meant to feed trees, vegetables, fruits,
Unerringly proceed to their pre-appointed roots.

"The summer's in her ark, and this sunny-pinion'd day

Is commission'd to remark whether winter holds her sway.
Go back, thou dove of peace, with the myrtle on thy wing,

Say that floods and tempests cease, and the world is ripe for spring.

"Thou hast fann'd the sleeping earth till her dreams are all of flowers And the waters look in mirth for their overhanging bowers;

The forest seems to listen for the rustle of its leaves,
And the very skies to glisten, in the hope of summer eves.

"The vivifying spell has been felt beneath the wave,

By the dormouse in its cell, and the mole within its cave;
And the summer tribes that creep, or in air expand their wing,
Have started from their sleep at the summons of the spring.

"The cattle lift their voices from the valleys and the hills,
And the feather'd race rejoices with a gush of tuneful bills;
And if this cloudless arch fill the poet's song with glee,
O thou sunny first of March, be it dedicate to thee!"

RISING AND SETTING OF THE SUN, FOR THE PARALLELS OF THE

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SUN.

SUN AND PLANETS AT GREENWICH.

MERCURY. VENUS. MARS. JUPITER. SATURN. URANUS.

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H. T. & J. Roche, Printers, 25, Hoxton-square, London.

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