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disk: that is, the disk is supposed to be divided by twelve parallel lines; and, if half of the disk is eclipsed, the quantity of the eclipse is said to be six digits; if one-fourth or one-twelfth part be obscured, then the quantity of the eclipse is said to be three digits or one digit. When the diameter of the shadow, through which the Moon must pass, is greater than the diameter of the Moon, then the quantity of the eclipse is said to be more than twelve digits.

Eclipses of the Moon are visible from all parts of the earth that have the Moon above the horizon at that time; but they are not seen at the very same time from places that differ in their longitude: thus, if one observer be fifteen degrees westward of another, this last must see the commencement or the termination of an eclipse an hour later than the former, because, on account of their difference of longitude, when it is ten o'clock with the one it will be eleven by the other. Hence from attentive observation, made at two different places, of the commencement or of the end of the eclipse, or of the arrival of the shadow at any particular spot of the Moon, the difference of longitude between those two places may be. determined.

The Moon always enters the shadow with its eastern side, and comes out of it with the same eastern side foremost; for the proper motion of the Moon being swifter than that of the Earth's shadow, the Moon approaches the shadow from the west, and passes through it with its eastern side foremost, leaving the shadow westward.

The duration of an eclipse is various, but it is never totally in darkness more than two hours, though, from the commencement to the termination of an eclipse, it may continue more than four hours.

To calculate the time, duration, and quantity of an, eclipse, the following particulars must be known or ascertained, and these may be obtained from the

Ephemeris, Nautical Almanack, and other astronomical tables, viz :—

The true time of the Moon's opposition, for the particular place for which the computation of the eclipse is intended.

The apparent time of the same, and for the same place.

The Sun's and also the Moon's place in the ecliptic.

The place of the Moon's node, and the Moon's latitude.

The Moon's distance from the Earth, or its apparent diameter, at the time; also

The Sun's and the Moon's horary motion.

The following particulars, relating to the approaching eclipse, are taken from the Nautical Almanack :→→ June 9th, Moon eclipsed, visible at Greenwich.

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Digits eclipsed 14° 56' from the south side of the shadow.

TABLE

Of the Eclipses of Jupiter's first Satellite, for the Month of June, that are visible in London and its Neighbourhood.

THE EMERSIONS MAY BE OBSERVED,

June 6, at 25 m. past 12 at night.

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On the 11th, at 44 m. past 9 at night, with a good glass, an eclipse of the second satellite may be observed.

The Naturalist's Diary.

Short is the reign of night, and almost blends
The evening twilight with the morning dawn.

WARM weather is, generally, established in June, yet the heat is rarely excessive :-showers of rain are very acceptable at the commencement of the month, as they tend to promote the growth of the young herbage. This month, however, is often cold and windy, like its predecessor, MAY, particularly within the last few years; so that we may well exclaim with the poet :

The seasons alter: hoary-headed frosts
Fall in the fresh lap of the crimson rose:
And on old Hyems' thin and icy crown,
An odorous chaplet of sweet summer buds
Is, as in mockery, set: the spring, the summer,
The childing autumn, angry winter, change
Their wonted liveries.

The innumerable beautiful herbs and flowers which, at this season of the year, meet our eye in every direction, appear designed only to ornament our earth, or to gratify our sense of smelling; but, upon a more intimate acquaintance with their peculiar properties and operations, we find, that, while they contribute to embellish our gardens, they also promote the purification and renovation of the atmosphere, which becomes contaminated from various causes.-We cannot again mention flowers, without quoting the pretty description of a modern poet :

Then the flowers on all their beds-
How the sparklers glance their heads!
Daisies with their pinky lashes,
And the marigold's broad flashes,

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The marigold, whose courtier's face
Echoes the sun, and doth unlace
Her at his rise, at his full stop
Packs, and shuts up her gaudy shop.

CLEAVLAND.

Hyacinth with sapphire bell
Curling backward, and the swell
Of the rose, full-lipped and warm,
Round about whose riper form
Her slender virgin-train are seen
In their close-fit caps of green:
Lilacs then, and daffodillies;
And the nice-leaved lesser lilies,
Shading, like detected light,
Their little green-tipt lamps of white;
Blissful poppy, odorous pea,
With its wings up lightsomely;
Balsam with his shaft of amber,
Mignonette for lady's chamber,
And genteel geranium,

With a leaf for all that come;
And the tulip, tricked out finest,
And the pink, of smell divinest;
And as proud as all of them
Bound in one, the garden's gem,
Heartsease, like a gallant bold,
In his cloth of purple and gold.—

Hunt's Descent of Liberty, pp. 28, 29.

The fields of clover (trifolium pratense), which are now in blossom, produce a delightful fragrance. Of this plant there are two varieties, the white and the purple; from the latter, the bees extract much honey. The bean blossoms also shed a still more exquisite odour.

Among the insect tribe, one of the most interesting is, in its perfect state, the angler's may-fly (ephemera vulgata), which appears about the 4th, and continues nearly a fortnight. It emerges from the water, where it passes its aurelia state, about six in the evening, and dies about eleven at night. Innumerable species of insects are called into life by the heat in this month. Among the most remarkable may be named the grasshopper (gryllus), the golden-green beetle (scarabæus auratus), various kinds of flies; the cuckoo-spit insect (cicada spumaria), and the stag-beetle (lucanus cervus). For a description of the two last, see T. T. for 1815, p. 214.

The several species of the gad-fly (œstrus bovis---

equi-and ovis), the ox, horse, and sheep gad-fly make their appearance in this month. When attacked by this insect, cattle endeavour to escape their tormentor, by taking refuge in the nearest pond; it being observed, that the gad-fly rarely attacks them when standing in the water.-See also T. T. for 1815, p. 216.

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About the beginning of the month, the pimpernel (anagallis arvensis), thyme (thymus serpyllum), the bitter sweet nightshade (solanum dulcamara), white bryony, the dog rose (rosa canina), and the poppy (papaver somniferum), have their flowers full blown. The poppy (says Cowley) is scattered over the fields of corn, that all the needs of man may be easily satisfied, and that bread and sleep may be found toge

ther:

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The fern owl may be seen, in the evening, among the branches of oaks, in pursuit of its favourite repast, the fern-chaffer (scarabæus solstitialis).

As yet the thrush roosts on the bloomy spray,
With head beneath his dew-besprinkled wing.

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