網頁圖片
PDF
ePub 版

add – 1.4003208, and the sum will be the log. of the number of seconds in the required refraction'.)

The Naturalist's Diary.

In mantle of Proteus clad,

With aspect ferocious and wild;
Now pleasant, now sullen and sad,

Now froward, now placid and mild. Such is the poet's character of this month, which is, in general, cold, with keen winds, the air clear and

· The formula, from which the above rule is immediately derived, are the following:

tang. u= sin. 2nR . tang. %.

and tang. nr = tang. NR . tang. I u; where n= 3.78, NR =6867", and % = the observed zenith distance.

But as these formulæ are adapted to the medium pressure of the atmosphere at the level of the sea, or 29.92 inches, and 320 of Fahrenheit's thermometer, the latter formula requires a reduction to bring it to the mean temperature, which should be about 570.2 of Fahrenheit's scale. In this case, if d be put for the number of degrees between the freezing point and the given temperature, the last of the above formulæ becomes

tang (1.00208 dar)= tang. R . tang. * 4. The following example will be of service to the young student in illustrating the preceding rule.

To find the refraction answering to 300 of observed altitude:-

1st.–Log. cotan. 300 = 10.2385606

add - 2.8230506 Sum-tang. 14 = 60 34 22" = 9.0010112 2d.-Ing. tang. & 4 = 30 17' 11" 8.7590721

add 2.5225024 | Tang, 6' 84”.5 = 394.5 = 7.2815745 3d.—Then log. 394".5 = 2.5960475

add - 1.4003208 Refrac. = 1'39'' = 99“.167 = 1,9963678

healthy. The superabundant moisture of the earth is dried up, and the process of vegetation is gradually brought on; those trees which, in the last month, were budding, now begin to put forth their leaves. The latest springs are always the most favourable, because, as the young buds do not appear so soon, they are not liable to be cut off by chilling blasts. Often may we say with the poet, in this and the following month,

Thou lingerest, Spring! still wintry is the scene,

The fields their dead and sapless russet wear;
Scarce does the glossy pile-wort yet appear
Starring the sunny bank, or early green

The elder yet its circling tufts put forth.
The sparrow tenants still the eaves-built nest,
Where we should see our martins' snowy breast

Oft darting out. The blasts from the bleak north
And from the keener east still frequent blow.
SWEET SPRING, thou lingerest! and it should be so;

Late let the fields and gardens blossom out!
Like MAN when most with smiles thy face is drest,
'Tis to deceive, and he who knows ye best,,

When most ye promise, ever most must doubt'. The melody of birds now gradually swells upon the ear. The throstle (turdus musicus), second only to the nightingale in song, charms us with the sweetness and variety of its lays. This bold and pleasing songster, from his high station, seems to command the concert of the grove, while, in the language of the poet,

The jay, the rook, the daw,
And each harsh pipe (discordant heard alone) . .
Aid the full concert, while the stock-dove breathes

A melancholy murmur through the whole, The linnet and the goldfinch join the general concert in this month, and the golden-crowned wren (motacilla regulus) begins its song. Rooks build and repair their nests. Rooks, crows, and pigeons, it has been proved, are by no means so detrimental to the

* Southey’s Metrical Tales, &c. p. 114.

farmer as is generally imagined, though many of them still commit great havoc among these birds, and use every means in their power to frighten them away. (See T. T. for 1816, pp. 86, 87.)

To the Crow.
Say, weary bird, whose level flight

Thus, at the dusky hour of night,
Tends thro' the midway air,

Why yet beyond the verge of day

Is lengthened out thy dark delay,
Adding another to the hours of care?

The wren within her mossy nest

Has hushed her little brood to rest;
The wood-wild pigeon, rocked on high,

Has cooed his last soft note of love,

And fondly nestles by his dove,
To guard their downy young from an inclement sky.

Each twittering bill and busy wing,

That fits thro' morning's humid spring,
Is still-list’ning perhaps so late

To Philomel's enchanting lay,

Who now, ashamed to sing by day,
Trills the sweet sorrows of her fate.

Haste, bird, and nurse thy callow brood,

They call on Heaven and thee for food,
Bleak-on some cliff's neglected tree;

Haste, weary bird, thy lagging flight-
. It is the chilling hour of night;

Fit hour of rest for thee'! - Those birds which have passed the winter in England now take their departure for more northerly re. gions. The fieldfares (turdus pilaris) travel to Russia, Sweden, and Norway, and even as far as Siberia. They do not arrive in France till December, when they assemble in large flocks of two or three thousand. The red-wing (turdus iliacus), which frequents the same places, eats the same food, and is very similar in manners to the fieldfare, also takes leave of this country for the season. Soon after, the woodcock

[ocr errors][ocr errors][merged small]

(scolopax rusticola) wings its aërial voyage to the countries bordering on the Baltic. Some other birds, as the crane and stork, formerly natives of this island, have quitted it entirely, since our cultivation and population have so rapidly increased.

Among the numerous songsters of this month, we must not omit to name the

Early, cheerful, mounting lark,
Light's gentle usher, Morning's clerk,

În merry notes delighting, and bearing up its hymn to heaven.' The skylark commonly forms its nest between two clods of earth, and lines it with dried grass and roots. In this she lays four or five eggs, and her period of incubation is about a fortnight, which office she generally performs twice a year. Her maternal affection is extremely interesting, both to the eye and to the heart. When her young are callow, she may be seen fluttering over their heads, directing their motions, anticipating their wants, and guarding them against the approach of danger.

The instinctive attachment, indeed, of the female skylark to her offspring, often precedes the period when she is capable of being a mother. A young hen bird,' says Buffon, 'was brought to me in the month of May, which was not able to feed without assistance. I caused her to be educated; and she was hardly fledged when I received from another place a nest of three or four callow skylarks. To these strangers she contracted a strong liking; she attended them night and day, though nearly as old as herself, cherished them beneath her wings, and fed them with her bill. Nothing could interrupt her tender offices. If the objects of her regard were torn from her, she flew back to them as soon as she was liberated, and disdained to think of effecting her own escape, which she had frequent opportunities of doing, while they remained in confinement. Her affection seemed to depriye her of every concern for self preser

vation; she neglected food and drink, and though now supplied the same as her adopted offspring, she expired at last, quite worn out with maternal solicitude. None of the young ones long survived her, but died one after another; so essential were her eares, which were equally tender and judicious to their preservation.'

The melody of the lark continues during the whole of the summer. It is chiefly, however, in the morn; ing and evening that its strains are heard ; and as it chaunts its mellow notes on the wing, it is the peculiar favourite of every person who has taste to relish the beauties of nature, at the most tranquil seasons of the day, particularly at dawn, when he 6 warbles high'

His trembling--thrilling ecstasy;
And lessening from the dazzled sight,

Melts into air and liquid light. : The lark mounts almost perpendicularly, and by successive springs, into the air, where it frequently hovers over its nest, and the objects of its dearest affections, at a vast height, without once losing sight of them. Its descent is in an oblique direction, unless when it is alarmed or attracted by its mate, when it drops to the earth like a stone.

So the sweet lark, high poised in air,

Shuts close his pinions to his breast,
If chance his mate's shrill call he hear,

; And drops at once into her nest. When it begins to rise, its notes are feeble and interrupted; but they gradually swell, as it ascends, to their full tone, and delight every ear that is enamoured of nature.

For nearly three months before Christmas, larks lose their voice, begin to assemble in flocks, grow fat, and are taken in prodigious numbers by the birdcatchers. As many as four thousand dozen have been caught in the vicinity of Dunstable alone, between September and February; nor are they less an

« 上一頁繼續 »