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map, and lines be drawn connecting these points, we shall have the path of the centre of the Moon's shadow across the globe. Whence it will be seen that the centre of the shadow, having entered the Earth's disc near the North Pole, will proceed between the Shetland Islands, and the coast of Norway, down the North Sea, and enter the continent of Europe on the coast of Westphalia, about half way between the Ems and the Weser. It will thence proceed, nearly in a straight line, across Germany and the Tyrol country, and enter the Gulf of Venice about midway between Trieste and Venice. Traversing that Gulf, it will cross the heel of Italy; and after skirting the coasts of Morea and Candia, will pass directly
over Alexandria, in Egypt; and finally leave the Earth in Arabia, near the Persian Gulf.'
The eclipse will also be more or less annular for about 130 geographical miles on each side of this dine; and the limb of the Moon will come into nearer contact with the upper or lower limb of the Sun, as the observer is situated on the west or the east of this central line of the shadow. Though the eclipse will not be annular beyond the limits above specified, it will be visible to the whole of Europe, and a great part of both Asia and Africa; but greater or less in magnitude, according to the situation of the spectator.
Mr. B. also suggests the principal phenomena which it would be desirable for those who have an opportunity to attend to. Such persons as are furnished with suitable instruments should carefully attend to and note down, not merely the phases of the eclipse, but such other appearances as present themselves. There is also one important part of these observations which may be ascertained with tolerable accuracy by any competent person, even without the aid of any particular apparatus, or at least with a common telescope of a small magnifying power; this is the formation and dissolution of the annulus. This may even be accomplished by means of a coloured glass and a clock or watch that beats seconds. The clock or watch should be regulated to mean time on the day of the eclipse; but if this cannot be done, the duration of the annular appearance may nevertheless be ascertained with the same accuracy, whether the watch indicate correct time or not; as all that is required for ascertaining this point is, that the watch should keep true time during the short interval of this duration.
Those persons who possess proper instruments, and have opportunities of using them, will of course attend to the usual circumstances in such cases: viz.
1. The time of the commencement of the eclipse.
4. The time of the end of the eclipse. Should any of our young readers not be provided with a coloured or smoked glass at the time the eclipse takes place, they may observe the image of the Sun in a bucket of water, or a vessel of oil, placed in a situation where the surface is not agitated by the wind. But it will be much better to be provided with a proper glass for this purpose; and one of the best that can be used is so easily prepared, and so effectual when properly done, that we shall insert the late Dr. Maskelyne's method of smoking glasses for this purpose. He observes, * Dark glasses should be used to defend the eye from the intensity of the Sun's light. - Transparent glasses, smoked over the flame of a candle or lamp, will give a more distinct and agreeable vision of the disc of the Sun than any tinged or coloured glasses will do. Provide two pieces of glass of a convenient length, not too thick (the common crown glass used for windows will do as well as any), wipe them clean and dry; warm them a little by the fire (if the weather be cold), to prevent their cracking when
applied to the flame of the candle; then draw one of them gently, according to its whole length, through the flame, and part of the smoke will adhere to the glass. Repeat the same operation, only leaving a little part at the end untouched, and so each time leave a further part of the same end untouched, til at last you have tinged the glass with several dyes, increasing gradually in blackness from one end of the glass to the other. Smoke the other glass in like manner; and apply the two glasses one against the other, only separated by a rectangular border, cut of glass or card paper, the smoked faces being opposed to each other, and the deepest tingés of both placed together at the same end. Tie the glasses firmly together with waxen thread, and they are ready for use. The tinge at one end should be the slightest possible, and at the other end so dark that you cannot see the candle through. By this contrivance, applied between your eye and the Sun, you will have the advantage not only of seeing the Sun's light white, according to its natural colour, and his image more distinct than through common dark glasses, but also of being able to intercept more or less of his light as you please, and, as the clearness or thickness of the air requires it, by bringing a dark er or lighter part of this combined dark glass before your eye; which will be a great convenience at all times, but particularly when the brightness of the Sun is liable to sudden changes from flying clouds.'
The Naturalist's Diary
For OCTOBER 1820.
Steams upwards as the cloudless orb of day
Basks in the splendour of his parting ray!
These deep'ning shadows, and that golden glow,
Athwart the glooin their mingled radiance throw.
The general state of the weather toward the close of autumn has a tendency to revive the natural spirits of those whose constitutions have been debilitated by the preceding heats. A great part of the day during the summer is too sultry for exercise ; but, as autumn advances, the air becomes more temperate, and the evenings, particularly, are serene and pleasant'.
The groves now lose their leafy honours; but, before they are entirely tarnished, an adventitious beauty, arising from that gradual decay which loosens the withering leaf, gilds the autumnal landscape with a temporary splendour, superior to the verdure of spring or the luxuriance of summer.
See yon huge oaks, bathed in the amber flood;
See, through its brightness shiues their mellow green,
And what their strength and beauty once have been.
O'er yon smooth meadow, as in ages past:
Deep anchored still, the fury of the blast.
Shelter the Hocks, as they recline, or graze
Full on the withered turf bis fiercest blaze.
Now to the dust, in ruins down they go,
Verdure above, but canker all beneath ;
Where ebbing life contends in vain with death.
From youth to age, from vigour to decay,
Among the meteorological phenomena of this month, may be oamed a very heavy full of snow and storm which happened on the 21st of October, 1819.
'Lines written at Ampthill Park. See also our last volame, p. 265.
Hips, haws, sloes, and blackberries, now adorn our hedges; and the berries of the barberry (berberis vulgaris), bryony (tamus communis), honeysuckle, elder, holly, woody-nightshade, and privet (ligustrum vulgare), afford a valuable supply of food for many of the feathered race, while passing their winter with us.
About the middle of the month, the common mar tin disappears; and, shortly afterwards, the smallest kind of swallow, the sand-martin, migrates. The Royston or hooded crow (corvus cornix) arrives from Scotland and the northern parts of England, being driven thence by the severity of the season. The woodcock retums, and is found on our eastem coasts.
Various kinds of waterfowl make their appearance; and, about the middle of the month, wild geese leave the fens, and go to the rye lands, to devour the young corn. Rooks sport and dive, in a playful manner, before they go to roost, congregating in large numbers. Stares assemble in the fen countries, in vast multitudes, and, perching on the reeds, render them unfit for thatching, and thus materially injure the property of the farmer.
The appearance of the gossamer, in this and the preceding month, leads us to speak of its cause in those wonderful spiders which produce the gossamer webs, by the buoyancy of which, it is conceived, they are enabled to sail in the air, and to mount to , prodigious elevations. These webs, which so frequently cover the surface of fallow and stubble fields, or form a delicate tracery upon our hedges, strung with the pearl-like drops of the morning dew, are most common in the autumn. In Germany, their appearance is so constant at this period, and so closely connected with the change of season, that they are popularly denominated by the expressive name, Der fliegender sommer,--the flying summer. The production of these webs was, with the natu