« ПредишнаНапред »
increasing heat produces a universal development of foliage and flowers. The earth opens, as it were, her bosom to the sun; all her veins feel the genial influence ; and a vital energy moves and works in all her blossoms, buds, and leaves. What was lately barrenness becomes fertility; from desolation and death starts up life and varied beauty, as if beneath the reviving footsteps of a present Deity. Hence result all the beautiful and amazing phenomena of spring.”—Duncan.
The first half of the month.—The fox and the martin suckle their young ones, and bring them animal food. The silvery gull and the crossbill retire from our shores to more northern latitudes to breed. The willow-wren, the blackcap, the redstart, and the nightingale arrive from the south : the swallow also makes its appearance, and skims along the surface of ponds and streams in quest of insects. The frog and the toad spawn early in this month, and the young are speedily hatched. The death-watch beetle (anobium tesselatum) leaves the wood, in which it passed its larvastate, and commences to make its peculiar ticking noise, somewhat quicker than the beats of a watch, and at intervals, consisting of seven or eight strokes at a time: this insect is only found in or about houses of long standing. The mole-cricket, (gryllotalpa vulgaris,) invited by the warmth of the sun, leaves its hiding-place; and the early cabbage-butterfly is seen dancing on powdery plumes in the solar beams.
The Chinese primrose, white oxalis, fritillary, wallflower, clarimond tulip, hyacinth, crown imperial, primrose daffodil, gentianella, common cyclamen, and various other interesting garden-plants, display their interesting flowers: while the fields exhibit in bloom ground-ivy, dandelion, wood wind-flower, bulbous buttercup, harebell, &c. A walk out into the lawns and woodlands on a fine morning in April yields considerable pleasure and interest.
“Hail! hail ! lovely morning! how sweet are thy dews,
“I hasten to meet thee, thy favours to share,
With transport I greet thee, and welcome thee e'er :
The last half of the month. The polecat suckles its young. The fieldfare departs. The wryneck and whitethroat arrive. The feathered tribes sing delightfully, and Philomela pours her music on the night's dull ear. The snake appears, and the barbel, the rud, and the roach spawn. Various species of insects appear, and arrest the attention of the entomologist.
Having named the return of the whitethroat, I will add a few remarks on this bird by the Hon. and Rev. W. Herbert. That gentleman says, “ There are no birds less shy and less pugnacious than whitethroats. They are amicable in the highest degree ; and having kept four or five cocks together in the same cage, I never saw an instance of the least dispute among them. They were extremely fond of each other; and one of them, having been taken from the rest to try if it would breed with a hen blackcap, died the next day, having, from vexation at finding itself separated from them, neglected to feed itself. I have seen the eldest of a nest give victuals to the youngest, when they were just beginning to feed themselves. Those which are caught become tame very quickly ; but such as are raised from the nest are the very perfection of amiability, and will come out gently the very moment their cage. door is opened, and never have the least fear of being handled. The blackcap, however tame while it requires to be fed, becomes very mistrustful as soon as it can shift for itself, especially the cocks, which are very wary, and in the wild state cannot in general be taken with a trap. I have taken many ben blackcaps in the cherrytrees with a limed rod; but never a cock. It is very difficult to get sight of the cock blackcap: while it is singing it is always on the watch, and shifting its place so as to avoid being seen. But the whitethroat sings boldly close to a person looking at it; and although Mr. White depreciates its song, I think it is only surpassed by the blackbird and thrush, except, of course, the matchless
ghtingale, with whose song all comparison of melody in this world is idle. In a room, the song of the whitethroat is very pleasing, and the young ones will sometimes learn some of the nightingale's notes; and their excessive familiarity and gentleness, and their healthy constitution, make them, to my mind, the most pleasing birds that can be kept in a cage. Their general food should be ground hempseed and bread scalded together, and a little German-paste given dry. Insects, and almost any thing which is not salt that man eats, may be given to them in small quantities as a treat; but much variety only makes them grow too fat.”
The blue and also the white lilac now ornament our shrubberies, while the blackthorn covers the hedges with its pretty blossom. The currant and gooseberry trees are in flower, and are much frequented by our common hive-bees. The cowslip appears beautiful on grass-lands, and the wild primrose in woods and coppices.
BRIEF ASTRONOMICAL NOTICES,
FOR APRIL, 1843.
BY MR. WILLIAM ROGERSON, of the Royal Observatory, Greenwich.
"Swift on the wings of thought from earth I rise,
To view yon distant, shining worlds of light;
To'adore that Power whose all-creating might
In countless myriads, through the milky-way;
And catch their murmurs as they nightly stray;
Till eastern skies proclaim the approach of day!
Thy power sustains their glorious destiny;'
“ The obliquity of the ecliptic to the equator was long considered as a constant quantity; and even so late as the end of the seventeenth century, the difference between the obliquity, as determined by ancient and modern astronomers, was generally attributed to inaccuracy of observation, and to a want of knowledge of the parallaxes and refraction of the heavenly bodies. It appears, however, from the most accurate modern observations, made at great intervals, that the obliquity of the ecliptic is diminishing; and the theory of universal gravitation fortunately supplies us with a satisfactory explanation of the phenomenon.
“ While the earth is revolving in the plane of the ecliptic, it is acted upon by all the planets in the solar system. The action of any of the planets when they are situated in the plane of the ecliptic, has a tendency only to alter the earth's gravity to the sun, or to accelerate and retard its motion ; but as all the planets move in orbits inclined to the ecliptic, their action upon the earth tends to bring the earth towards the plane of their orbits. The effect of this action, therefore, is to displace the ecliptic, or diminish the inclination of the earth's orbit to the plane of the orbit of the planet; but while the earth's orbit is thus changing its position, the equator of the earth is sustaining no change, and consequently there will be a variation in the obliquity of the ecliptic to the equator. Along with this variation there will also be a small precession in the equinoctial points.* These changes, however, are very small, and scarcely become apparent till after the lapse of ages. According to La Grange, the diminution in the obliquity of the ecliptic, and the precession of the equinoxes produced by the different planets in a century are,
* The precession arising from the combined action of the sun and moon amounts to 50". 2 every year.
+ 0". 85 Venus
+ 8.87 Mars
2 . 11
2 . 39
Total effect .... 50". 00
+ 8". 03
“By comparing about one hundred and sixty observations of the obliquity of the ecliptic, made by ancient and modern observers, with the obliquity of 23° 28' 16", as observed by Tobias Mayer, in 1756, we have found, from a view of all the results, that the diminution of the obliquity of the ecliptic, during a century, is 51" ; a result which accords wonderfully with the best observations.". Dr. Brewster.
The above quotation I have inserted in consequence of having received two letters from the readers of this periodical, asking my opinion respecting an article entitled, “A change in the ecliptic of the earth,” which has appeared in the “ Bradford Observer,” &c., taken from “ The New-York Daily Mail.” It is evident that the writer speaks extravagantly in saying that, “ If no counteracting influence intervenes, there will soon be a perceptible change in the seasons,” &c. The thoughtful reader, in looking over the above remarks of Dr. Brewster, which are founded on truth and experience, will dismiss all ideas of “ changes of seasons arising from the variation of the obliquity of the ecliptic. I would add, that careful observations give the mean obliquity for the beginning of the present year (1843) 23° 27' 35", being only 41" less than the quantity obtained by Mayer eighty-seven years ago. The other remarks in the article I have named, are equally, if not more, extravagant, and opposed to those plans which Infinite Wisdom, with infinite goodness, has devised for the benefit of the human family, and that of the inhabitants of other worlds connected with the solar system.
“Great Artist! Thou whose finger set aright
The Sun rises on the 1st, at London, at thirty-seven minutes past five, and sets at thirty-one minutes after six : on the same day he rises at Edinburgh at thirty-four minutes past five, and sets at thirty-four minutes after six. The Sun rises on the 21st, at London, at fifty-four minutes past four, and sets at four minutes after seven :
on the same day he rises at Edinburgh at forty-three minutes past four, and sets at sixteen minutes after seven.
The Moon sets on the 1st at thirty-eight minutes past eight in the evening, and on the 4th about midnight: she is half-full on the 7th, and sets on the 8th at ten minutes past two in the morning. The Moon is due south on the 9th at twelve minutes before eight, and on the 11th at half-past nine, in the evening: she is full on the 14th, at twenty-nine minutes past two in the afternoon; and presents her fully-illuminated disk in the south-eastern horizon on the 15th at a few minutes before nine at night. The Moon rises on the 16th at a quarter past ten, and on the 17th at half-past eleven: she enters on her last quarter on the 21st, and presents her waning crescent at daybreak on the 22d in the eastern skies: she rises on the 24th at forty minutes past two, and on the 26th at ten minutes after three, in the morning. The Moon changes on the 29th, at nineteen minutes after four in the afternoon; and exhibits her delicate crescent near the north-western horizon on the evening of the 30th, setting about a quarter before nine o'clock.
MERCURY is unfavourably situated for observation during this month.
Venus is still “the morning star;" but rising only about an hour before the Sun, renders her only to be seen on very clear mornings: she is near the Moon on the 26th day.
Mars becomes a somewhat conspicuous object in the mornings: he is due south on the 1st at twenty-three minutes past four, and on the 20th at half-past three : on the 18th he is near the Moon. The ruddy colour which distinguishes the light of this planet from that of the rest of the orbs of our system, seems to indicate an ochrey tinge in his general soil, like what the red sandstone districts on the earth may possibly offer to the inhabitants of Mars, only more decided.
“See, Mars, alone, runs his appointed race,
JUPITER, at the beginning of the month, appears not far from Venus : he rises on the 1st at ten minutes past four, and on the 26th at twenty minutes before three, in the morning : on the 23d he is in conjunction with the Moon.
SATURN appears every clear morning between Mars and Jupiter : he rises on the 6th at seventeen minutes before three, and on the 22d at a quarter before two o'clock. This planet is in the neighbourhood of the Moon on the 21st day.
REGULUS, the Lion's Heart, appears in the south after sunset : this fixed star is on the meridian on the 8th about nine o'clock, and on the 22d at an hour earlier : on the 10th this star appears not far from the Moon.