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planets be denoted by D and d, and their times of revolution by T and t; we shall have

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Now as the distance between the Sun and the earth has been found, and the time of its revolution also ascertained, if these be substituted instead of d and t in this formula, the mean distance of any of the planets from the Sun will be attained in terms of the earth's distance from the Sun. Reducing this formula to numbers, and taking the earth's distance for unity, which is the term in which astronomers usually compute the planetary distances, gives

3

D=V

T2
(365.2564)2

.01957 T3.

Now, by applying this formula to each of the planets respectively, we shall obtain their relative mean distances from the Sun, as stated in the following table; viz.

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As these relative distances are expressed in that of the earth from the Sun, if they be severally multiplied

by the number of miles already found for that distance, we shall have their absolute distances in English miles, as follow, viz.

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The immense distance of these bodies from the centre of the system, when expressed in miles, renders the numbers difficult to be remembered; but this difficulty may be avoided, and sufficient accuracy preserved for all common purposes, by taking only the millions and the nearest small fraction, as follows:

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Besides the real and comparative distances of the planets from the Sun, as above stated, their greatest and least distances from the earth are sometimes computed by astronomers. The greatest distance of a planet from the earth is equal to the sum of the aphelion distances of the earth and the planet.

The least distance of an inferior planet from the earth is the difference between the perihelion distance of the earth and the aphelion distance of the planet. But for a superior planet, the least distance is equal to the difference between the perihelion distance of the planet and the aphelion distance of the earth. The least distance of each of the old planets from the

earth, in English miles, is contained in the following

table; viz.

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The least distance of the Sun and Moon from the earth are also,

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birds sing,

Thy beams are sweet, beloved Spring!
The winter shades before thee fly;
The bough smiles green, the young
The chainless current glistens by;
Till countless flowers, like stars, illume
The deepening vale and forest gloom.
Oh! welcome, gentle guest from high,
Sent to cheer our world below,
To lighten sorrow's faded eye,
To kindle nature's social glow:
Oh! he is o'er his fellows blest,

Who feels thee in a guiltless breast.

THE superabundant moisture of the earth is now 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; and the various appearances of nature announce the approach of SPRING'. The latest springs, however,

See a beautiful Elegy on the Approach of Spring' in our last volume, p. 85.

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.

Slow teeming Nature, struggling, meets the day,
Though ample promise smiles in every bud;
And silken softness all the tender leaves
Unfolds, while the rude breeze, with lips of ice,
Imprints a fatal kiss, and cruel chills
The mild and purple flush of early hope.
Fresh verdure delicately clothes the shrub ;
First of the garden train, the gooseberry bursts,
And puts its fearless blossom forth. More slow
The currant swells. The lilac's emerald gems
Seem eager to expand.

BIDLAKE.

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.

Sweet thrush! whose wild untutored strain
Salutes the opening year;

Renew those melting notes again,

And sooth my ravished ear.

Though in no gaudy plumage drest,
With glowing colours bright;
Nor gold, nor scarlet, on thy breast,
Attracts our wond'ring sight;

Yet not the pheasant, or the jay,
Thy brothers of the grove,
Can boast superior worth to thee,
Or sooner clain our love.

M. RIDDELL.

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 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.)

Among the numerous singing birds which delight us with their notes in the spring, the lark must not be forgotten. The melody of this little creature continues during the whole of the summer. It is chiefly, however, in the morning 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.-See some interesting particulars of this bird in our last volume, p. 76.

Sweetest warbler of the skies,
Soon as inorning's purple dyes
O'er the eastern mountains float,
Wakened by thy merry note,
Thro' the fields of yellow corn,
That Mersey's winding banks adorn,
O'er green meads I gaily pass,
And lightly brush the dewy grass.

I love to hear thy matin lay,
And warbling wild notes, die away;
I love to mark thy upward flight,
And see thee lessen from my sight:
Then, ended thy sweet madrigal,
Sudden swift I see thee fall,

With wearied wing, and beating breast,
Near thy chirping younglings' nest.

Ah! who that hears thee carol free
Those jocund notes of liberty,
And sees thee independent soar,
With gladsome wing, the blue sky o'er,
In wiry cage would thee restrain,
To pant for liberty in vain ;
And see thee 'gainst thy prison grate
Thy little wings indignant beat,
And peck and flutter round and round
Thy narrow, lonely, hated bound;
And yet not ope thy prison door,
To give thee liberty once more?

W. SMITH.

In this month, trouts begin to rise; blood-worms. appear in the water; black ants (formica nigra) are

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