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The Envelope. The envelope is that part of the comet which surrounds the nucleus only on that side which is next to the sun and opposite to the tail; in some instances it is united with the nucleus,-in general, however, it is situated at a greater or less distance from it; the envelope passes in two streams of light on opposite sides of the nucleus, and forms that singular and well known phenomenon called the tail. The matter which composes the envelope seems to consist of the matter of the nucleus itself, raised by the solar action ; the envelope does not appear till the comet is near the sun, when it gradually rises from the nucleus, and sinks again as the comet retreats from the sun; in some comets several of these nebulous envelopes have been observed, arranged in strata, the interior being the brightest, and the exterior less brilliant and more diffuse.
Hast thou ne'er seen the comet's flaming flight?
OF THE SUN'S RISING AND SETTING, RIGHT ASCENSION,
DECLINATION, AND EQUATION OF TIME.
Day. Moon. Mercury. Venus. Mars. Jupiter. Saturn. Uranus.
SOLAR PHENOMENA. The northern regions of the earth are arrayed with the beauty of spring. The noon exhibits a canopy of boundless azure, the night reveals the wintry constellations sinking in the west, with the advance of those stars to the mid-beaven, which declare that the time of the singing of birds is come, and that the summer is advancing. The flower and the star appear each in its season, and send forth, the one its ray, and the other its fragrance, with unfailing precision. The lovely train of Flora delights the senses with its perfume and beauty; the thrush and blackbird fill the woods with melody, and Arcturus in the east, and Capella in the zenith, shed forth their brightest scintillations: the rose, the nightingale, and bright star in the hand of the Virgin, bloom, sing, and shine together; the violet from its shady bank, the lark from “ its watch-tower in the sky,” send forth their tribute of odour and harmony, as the stars in the soft Pleïades fade away in the glowing twilight of the vernal eve. As the fervid heat of summer increases, and light is more copiously diffused over the northern world, the stars shine with a subdued brilliancy; the melody of the grove ceases; the Aster tribe of flowers,
with their diversified radiations, decorate the field and the garden, and with pure adoration expand their bright flowrets to receive the full effulgence of the summer sun.
The sun enters Gemini at 54 min. after 2 of the morning of the 21st of this month.
Phases of the Moon.
New Moon, 29th .... 56 ........ 11 night. Conjunctions of the Moon with the Planets and Stars. May 8th, with Saturn ........ at 9 evening.
15th, .... p in Ophiuchus .. 6
28th, .... Venus ........... 6 evening. The conjunction with Saturn will prove an occultation; the immersion will take place at the dark limb of the moon, and about an hour after it has passed the meridian.
Transit of Mercury. It is probable that the most interesting celestial phenomenon that the astronomer can behold, is a transit of a planet across the disc of the sun; it is interesting as well for its singularity as its rarity; it can occur only with the inferior planets, and with these in the present century, only thirteen can occur with Mercury, and two only with Venus in the same period. On the 5th of