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ASTRONOMICAL PHENOMENA.

about half-past nine in the afternoon. Its increasing distances from the Sun and Earth produce a corresponding diminution of the light. We are ignorant of the precise laws which regulate this diminution, since we are ignorant of the physical constitution of these bodies; but it is usually assumed that the light diminishes as the product of the squares of the distances from the Sun and Earth increases; which is equivalent to the assumption that the apparent light of the Comet is independent of the absolute magnitude of the body, and of the direction from which it is viewed.

MERCURY is now receding eastward from the Sun, in the part of his orbit remote from us. The apparent angular distance will be considerable toward the close of the month; yet, so rapid is the planet's southward motion in declination, that his stay above the horizon after the Sun's will, even then, amount to not quite half an hour. On the 15th he will be in the plane of the Earth's orbit going southward. On the 17th he will have the same right ascension as Venus; but will be eight degrees and a half farther north. On the morning of the 26th he will be in aphelion,

VENUS is approaching the Sun on the eastern side, and will continue to do so till the morning of October 1st, when she will be nearly in a line between the Earth and Sun. Her apparent diameter toward the end of the month will be very nearly one minute of space. under With a magnifying power of 300, she would therefore appear an angle ten times greater than the Moon subtends to the naked eye, and her superficial area would appear a hundred times greater. Her apparent motion in right ascension will be eastward till the Sth; afterwards westward, or retrograde. The motion in declination will be southward till the 16th. On the 17th she will be at her greatest distance from the Earth's orbit at the southern side.

MARS is now in Cancer, near the cluster of stars called Præsepe. JUPITER has replaced Venus as the evening star. On the afternoon of the 4th he will be due south at eleven, on the 18th at ten, o'clock. These are the times of his greatest altitude, 25°; and, consequently, those most favourable for observation. The evenings of the 5th, 12th, 14th, 21st, 23d, and 28th will be richest in phenomena presented by this planet and his satellites. His apparent diameter is 45".

SATURN rises at hours more seasonable for observation than last month. On the 2d or 3d he attains his greatest northern declination, 22°, 14', 50". He will be near the Moon on the 4th. This planet is approaching the Earth, and thus slightly increasing in apparent magnitude.

On the 23d, at three hours in the afternoon, the plane of the equator will pass through the centre of the Sun. Proceeding northward, and retaining its parallelism, with the exception of a very

slight nutation, the Sun appears to us to go southward. It is worthy of remark that the time between the vernal and autumnal equinox is one hundred and eighty-six days eleven hours, leaving only one hundred and seventy-eight days nineteen hours from the autumnal to the vernal. During the former period, the Earth passes through the part of its orbit most remote from the Sun: it thus traverses a longer route and with a slower motion than in the latter period..

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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THE

YOUTH'S INSTRUCTER

AND

GUARDIAN.

NOVEMBER, 1855.

RICHARD BENTLEY, D.D.

(With a Portrait.)

OULTON, a village in the West Riding of Yorkshire, situate between Leeds and Wakefield, may boast of being the birthplace of one of the most accurate Grecians and most litigious Ecclesiastics that ever adorned or troubled a University. In both characters he rose to heroic eminence. His grandfather, a Captain in the army of Charles I., died a prisoner of war in Pontefract Castle. His father, Thomas Bentley, possessed a small farm at Woodlesford, in the parish of Oulton; and his mother was daughter of a stonemason in the same parish. Richard, born on the 27th of January, 1661-62, was baptized with the name of his maternal grandfather, who undertook, as soon as necessary, the cost of his education. But his mother, although of humble rank, must also have been well educated; for she taught him the Latin Accidence. Furnished with these elements, he went early to a day-school at Methley, then to the Grammar-School at Wakefield, thence to Cambridge, and was entered as a sizar in St. John's, before he had completed his fifteenth year. There he had the privilege of hearing Isaac Newton-afterwards Sir Isaac-lecture. It is needless to say that he made good use of his time; and as youth barred him from attaining to a Fellowship, VOL. XIX. Second Series.

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