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pose that, in consequence of some concussion, or other cause, the outer shell fell down to the inner body, and left only the ring at the greater distance from the centre. This conjecture is, in some measure, corroborated from the consideration that both the planet and its ring perform their rotations about the same common axis, and in very nearly the same time. Dr. Herschel, from the observations he made on the planet, concludes in the following words: • It does not appear to me that there is sufficient ground for admitting the ring of Saturn to be of a very changeable nature, and I guess that its phenomena will hereafter be so fully explained as to reconcile all observations. In the mean time, we must withhold a final judgment of its construction, till we can have more observations. Its division into two very unequal parts can admit of no doubt.'
The diameters of Saturn are not equal; they are, probably, in the proportion of about 11 to 10. This » form, compared with that of Jupiter, leads one to conclude that Saturn turns rapidly round his shorter axis, and that the ring moves in the plane of his equator. Huygens observed five belts upon this planet nearly parallel to the equator. Besides the ring above mentioned, Saturn has seven satellites or moons continually circulating about him. The orbits of all these satellites, except the fifth, are nearly in the same plane, which makes an angle with the plane of Saturn's orbit of about 31°; and, by reason of their being inclined at such large angles, they cannot pass across their primary, or behind it, with respect to the earth, except when very near their nodes ; so that eclipses of them happen much more seldom than of the satellites of Jupiter,
Till the time of Herschel, five satellites only were known as connected with this planet: this astronomer, in the years 1787 and. 1788, discovered two others: these are nearer to Saturn than any of the other five, but, to prevent confusion, they were de
Till the connected with and. 1788, disc any of the
nominated the 6th and 7th satellites. The fifth satellite has been observed to turn once round its axis exactly in the time in which it revolves round Saturn ; and, in this respect, it resembles our Moon.
The Naturalist's Diary.
Sad wears the hour! heavy and drear
GLOOMY as this month usually is, yet there are some intervals of clear and pleasant weather: the mornings are, occasionally, sharp, but the hoarfrost is soon dissipated by the Sun, and a fine open day follows. Of November scenery, on the other side of the Tweed, WALTER Scott has drawn a pleasing picture; much of it, however, applies equally to more southern regions.
November's sky is chill and drear,
And yet a watery sunbeam shines ; !
The withered sward and wintry sky, .
His dogs 'no merry circles wheel,
The trees are now stripped of their foliage. The separation of the leaves from their branches is termed the fall; and, in North America, the season in which this takes place is universally known by that name. The falling of leaves is not always in consequence of the injuries of autumnal frosts, for some trees have their appropriate period of defoliation, seemingly independent of external causes. The lime (tilia europæa) commonly loses its leaves before any frost happens; the ash seems, on the contrary, to wait for that'event; and at whatever period the first rather sharp frost takes place, all its leaves fall at once. The fall of the leaf can be considered only as a sloughing or casting off diseased or worn-out parts,' whether the injury to their constitution may arise from external causes or from an exhaustion of their vital powers. · Hence a separation takes place, either in the footstalk, or more usually at its base; and the dying part quits the vigorous one, which is promoted by the weight of the leaf itself, or by the action of autumnal winds upon its expanded form'. Sometimes, as in the hornbeam, the beech, and some oaks, the swelling of the buds for the ensuing season is necessary to accomplish the total separation of the old stalks from the insertions,
How fall’n the glories of these fading scenes!
they decay often parhieit heates a related is thime, o
Leaves undergo very considerable changes before they fall: ceasing to grow for a long time previous to their decay, they become gradually more rigid and less juicy, often parting with their pubescence, and always changing their healthy green colour to more or less of a yellow, sometimes a reddish hue'. One of the first trees that becomes naked is the walnut; the mulberry, horse-chesnut, sycamore, lime, and ash, follow. The elm preserves its verdure for some time longer : the beech and ash are the latest deci. duous forest trees in dropping their leaves. All lopped trees, while their heads are young, carry their leaves a long while. Apple-trees and peaches remain green very late, often till the end of November: young beeches never cast their leaves till spring, when the new leaves sprout, and push them off: in the autumn, the beechen leaves turn of a yellow deep chesnut colour.'-(White.) . .
That highly-esteemed fish, the salmon, now ascends rivers to deposit its spawn in their gravelly beds, at a great distance from their mouths. In order to arrive at the spots proper for this purpose, there are scarcely any obstacles which the fish will not surmount. They will ascend rivers for hundreds of miles; force themselves against the most rapid streams, and spring with amazing agility over cataracts of several feet in height. They are taken, according to Mr. Pennant, in the Rhine, as high as Basil: they gain the sources of the Lapland rivers, in spite of their torrent-like currents : they surpass the perpendicular falls of Leixlip, Kennerth, and Pont Aberglasslyn. At the latter of these places, Mr. Pennant assures us that he has himself witnessed the efforts of the salmon, and seen
"American trees and shrubs in general, and such European ones as are botanically related to them, are remarkable for the richtints of red, purple, or even blue, which their leaves assume before they fall. Hence the autumnal foliage of the woods of North America is, beyond all imagination, rich and splendid.
scores of fish, some of which succeeded, while others miscarried in the attempt, during the time of observation. At this time, nets or baskets are placed under the fall, and numbers are taken after an unsuccessful leap'. It may be added, that the salmon, like the swallow, is said to return, each season, to the self-same spot to deposit its spawn.'
The value of this article of life has advanced equally with every kind of food, even in situations where salmon were most abundant. The amazing disproportion in the present price of Severn salmon to that of twenty or thirty years ago, when it was sold from threepence to sixpence per lb., is attributed, in a great degree, to the several weirs (contrary to Act of Par. liament) upon the river, constructed so as to prevent the smallest salmon fry from escaping, as they proceed towards the sea. It is a known fact, that the fry have been taken in such quantities, that the captors have been obliged to throw them away. Another mode of incalculable destruction arises from the practice of netting the fords when the water is low, by which means the salmon spawn, deposited upon the sand and gravel, being loosened by the net, is swept away, and becomes food for fish of an inferior quality, such as chub, roach, dace, &c. The above, combined with other causes, such as the speedy conveyance now afforded, not only to the metropolis, but to all
! A curious mode of taking this fish, called salmon-hunting (as practised at Whitehaven), is mentioned by Mr. Bingley: When the tide récedes, what fish are left in the shallows are discovered by the agitation of the water ;—the hunter, with a three-pointed barbed spear, fixed to a shaft fifteen feet long, plunges into these pools at a trot, up to the belly of his horse. He makes ready his spear, and, when he overtakes the salmon, strikes the fish with alinost unerring aim; that done, by a turn of the band, he raises the salmon to the surface, wheels his horse towards the shore, and ruós the fish on dry land without dismounting. From forty to fifty fish have been killed in a day; ten are, however, no despicable booty.'