always perpendicular to this line, the circles parallel to the equator will be unequally divided at different parts of the orbit. The inequality in the distribution of the seasons, by which the inhabitants of the northern hemisphere of the globe enjoy a greater portion of the Sun by about eight days in the year, arises from a cause that shall now be illustrated. The imaginary great circle in the heavens, called the ecliptic, is in truth the representation of the ellipse in which the earth travels round the Sun: all the irregularities, therefore, of the ellipse will, by observers, be transferred to the circle which represents it, and the four portions intercepted by the equinoctial and solstitial points, though represented each by an arc of 90°, will not be described in equal times, because they do not represent such portions of the ellipse as are originally so described. The point of the ecliptic, representing that point of the ellipse in which the Sun and earth are nearest to each other, is called the perigee; and the summer and winter months can never be equal, but in the singular instance of the coincidence of the perigee with one or other of the equinoctial points. The solar perigee has a progressive motion in the ecliptic, which it is found to complete in about 20,000 years; and it is a very remarkable circumstance, that this curious coincidence of the perigee with the autumnal equinox took place about the time when chronologists suppose the world to have been created, or about the year 4000 before the birth of Christ. At that time, each hemisphere enjoyed an equal portion of the Sun's light and heat, and since then the northern hemisphere had gradually the advantage, and the maximum of inequality took place in the year 1250. Since that time the advantage has gradually diminished, though it is very considerable. It will diminish till the year 6472, when the perigee, coinciding with the vernal equinox, will again equally divide the summer and winter periods between the P two hemispheres; after which, the southern inhabitants of the globe will enjoy the advantage of having the greatest share of the Sun for above 10,000 years. -We shall resume the subject of the earth in our next month's discussions. The Naturalist's Diary. Hail, bounteous MAY, that dost inspire THIS month is usually considered as the most delightful of the whole year, and has long been the Muse's favourite theme; although much that is said of its beauties applies better to more southern climates, or, indeed, to our month of JUNE, which is, commonly, entitled to all the praises that the poets have lavished upon MAY. This month, however, is remarkable for the profusion of verdure which it exhibits: Nature's carpet is fresh laid, and nothing can be more grateful than to press its velvet surface When May is in his prime, Then may each heart rejoice; When May bedecks each branch with green, The lively sap creeps up Into the blooming thorn; The flowers which cold in prison kept Now laugh the frost to scorn. All Nature's imps1 triumphs Whiles joyful May doth last; When May is gone, of all the year The pleasant time is past2. The scenery of a May morning is, not unfrequently, as beautiful as can possibly be conceived; a serene 1 Sons. 2 Paradise of Dainty Devices, Ed. 1576. sky, a pure air, a refreshing fragrance arising from the face of the earth, and the melody of the feathered tribes, all combine to render it inexpressibly delightful, to exhilarate the spirits, and to call forth a song of grateful adoration. The latest species of the summer birds of passage arrive about the beginning of this month. (1) The goatsucker, or fern-owl (caprimulgus Europeus), makes its appearance only in the dusk of the evening, to search for prey, and, while perched on a tree, utters a dull jarring noise. It feeds on insects, and is a great destroyer of the cock-chaffer or dor-beetle. This bird is found in every part of the old Continent, from Siberia to Greece, África, and India; it leaves England about the end of August. (2) The spotted fly-catcher (musicapa grisola) is the most mute and familiar of all our summer birds; it builds in a vine or sweet briar, against the wall of a house, or on the end of a beam, and sometimes close to the post of a door, where people are going in and out all day long : it returns to the same place year after year. The sedge-bird (motacilla salicaria) is found in places where reeds and sedges grow, and builds its nest there, which is made of dried grass, tender fibres of plants, and lined with hair. It sings incessantly, night and day, during the breeding time, and imitates, by turns, the notes of the sparrow, the skylark, and other birds, from which it is called the English mock-bird. The arduous time of incubation is now come, and birds are sedulously employed in hatching and rearing their young: Each secret nook, each silent shade 1 Thence termed the night-jar by Mr. Bewick. 2 The pied fly-catcher (muscicapa atricapilla) is nowhere common, but is most plentiful in Yorkshire, Lancashire, and Derbyshire. The insect tribes continue to add to their numbers; among these may be named several kinds of moths and butterflies (papilio atalanta, cardamines, ægeria, &c.1), field-crickets (gryllus campestris), the chaffer or may-bug (scarabæus melolontha), and the forest-fly (hippobosca equina), which so much annoys horses and cattle. The female wasp (vespa vulgaris) appears at the latter end of the month. About this time bees send forth their early swarms; and the female glow-worm (lampyris noctiluca) is seen on dry banks, about woods, pastures, and hedgeways, exhibiting, as soon as the dusk of the evening commences, the most vivid and beautiful phosphoric splendour, in form of a round spot of considerable size. The male is smaller than the female, and is provided both with wings and wing-sheaths: it is but rarely seen; and it seems, even at present, not very clearly determined whether it be luminous or not. The splendour exhibited by the female in this species, is probably ordained for the purpose of attracting the male: The chilling night-dews fall; away, retire; For see, the glow-worm lights her am'rous fire! WHITE. In again naming the butterfly, we cannot forbear to copy some exquisite stanzas of an anonymous poet : When, bursting forth to life and light, The butterfly, on pinions bright, Launched in full splendour on the day; Unconscious of a mother's care, Her slender form, ethereal, light, About the commencement of the month the flowers of the lily of the valley (convallaria maialis) and the chesnut tree (fagus castanea) begin to open; the tulip tree (liriodendron tulipfera) hath its leaves quite out, and the flowers of the oak (quercus robur), the Scotch fir (pinus sylvestris), the honeysuckle, and the beech, are in full bloom. Towards the middle, the flowers of the white thorn are quite out, and the mulberry tree (morus nigra) puts forth its leaves; the walnut (juglans regia) hath its flowers in full bloom; the flowers of the garden rose also begin to open. The lilac (syringa vulgaris), the barberry (berberis vulgaris), and the maple (acer campestre), are also in flower. At the latter end of the month, rye (secale hybernum) is in ear; the mountain ash (sorbus aucuparia), laburnum (cytisus laburnum), the guelder rose (viburnum opulus), clover (trifolium pratense), columbines (aquilegia vulgaris), the alder (rhamnus frangula), and the wild chervil (chorophyllium temulum), have their flowers full blown. The germander (veronica chamadrys) is seen in hedges, and various species of meadow-grass are now in flower. Hearts-ease (viola tricolor) in corn-fields; the butter-cup (ranunculus bulbosus1) spread over the meadows; the cole-seed (brassica napus) in cornfields, bryony (brionia dioica), and the arum or cuckoo-pint, in hedges, now show their flowers. In this and in the succeeding month, nothing so much attracts our attention as the order of succes Trembling awhile, with joy she stood, These flowers do not tinge the butter, as erroneously supposed, with its rich yellow colour, at this season; for the cows will not touch them. |