At Epping Forest, the scene is very different, but not a whit the less lively. There are no picture-galleries or pleasure-gardens, but there is the Forest to roam in, full of noble trees, in endless sinuous avenues, crowned with the 'scarce intruding sky,' among which the joyous holiday-makers form a finer picture than was ever painted yet. Then there are friendly foot-races and jumping-matches, and leap-frogging, and black-berrying, and foot-balling, and hockey-and-trapping, and many other games besides, in addition to the dancing and the ring-kissing. Epping and Hainault Forests are essentially the lungs of Whitechapel and Spitalfields. Their leafy shades are invaded all the summer long by the van-borne hosts of laborious poverty. Clubs, whose members invest but a penny a week, start into existence as soon as the leaves begin to sprout in the spring; with the first gush of summer, the living tide begins to flow into the cool bosom of the forest; and until late in the autumn, unless the weather is prematurely wintry, there is no pause for a day or an hour of sunshine in the rush of health-seekers to the green shades. The fiat has gone forth from the government for the destruction of these forests, for the felling of the trees and the enclosure of the land. Will the public permit the execution of the barbarous decree? We trust not.

Notwithstanding all that has been said, and so justly said, of the notorious improvidence of the poor, it will be seen from the above hasty sketches, that they yet can and do help themselves to many things which are undeniably profitable and advantageous to them: they only want, in fact, a motive for so doing—a foregone conviction that the thing desiderated is worth having. Now, here is ground for hope—an opening, so to speak, for the point of the wedge. That the very poor may be taught to practise self-denial, in the prospect of a future benefit, these clubs have proved; and we may confess to a prejudice in their favour, not merely from what they have accomplished, but from a not unreasonable hope, that they may perchance foster a habit which will lead to far better things than even warm chimney-corners, greenwood holidays, roast geese, and plum-pudding.

ARAGO ON THE SUN

In the Annuaire of the Bureau des Longitudes, recently published in Paris, appears a paper by the distinguished astronomer Arago—'On the Observations which have made known the Physical Constitution of the Sun and of different Stars; and an Inquiry into the Conjectures of the Ancient Philosophers, and of the Positive Ideas of Modern Astronomers on the Place that the Sun ought to occupy among the Prodigious Number of Stars which stud the Firmament'—in which all that appertains to the subject is so ably condensed, as to afford material for a popular summary, which we purpose to convey in the present article. The eclipse of the sun of last July, by enabling observers to repeat former observations and test their accuracy, furnished some of the results which serve to complete the paper in question, and which may be considered as settled, owing to the improvements continually taking place in the construction of instruments. Although astronomy is the exactest of sciences, its problems are not yet all fully solved; and for the determination of some of these, observers have to wait for years—in certain instances, for a century or more, until all the circumstances combine for a favourable observation. From the days of the Epicurean philosopher, who, judging from appearances, declared the sun to be no more than a foot in diameter, to those of living calculators, who give to the orb a diameter of 883,000 miles, there has been a marvellous advance. In these dimensions, we have a sphere one million four hundred thousand times larger than the earth. 'Numbers so enormous,' says M. Arago, 'not being often employed in ordinary life, and giving us no very precise idea of the magnitudes which they imply, I recall here a remark that will convey a better understanding of the immensity of the solar volume. If we imagine the centre of the sun to coincide with that of the earth, its surface would not only reach the region in which the moon revolves, but would extend nearly as far again beyond.' By the transit of Venus in 1769, it was demonstrated that the sun is 95,000,000 miles from the earth; and yet, distant as it is, its physical constitution has been determined; and the history of the successive steps by which this proof has been arrived at, forms one of the most interesting chapters in the progress of science.

It was in 1611 that Fabricius, a Dutch astronomer, first observed spots on the eastern edge of the sun, which passed slowly across the disk to the western edge, and disappeared after a certain number of days. This phenomenon having been often noted subsequently, the conclusion drawn therefrom is, that the sun is a spherical body, having a movement of rotation about its centre, of which the duration is equal to twenty-five days and a half. These dark spots, irregular and variable, but well defined on their edge, are sometimes of considerable dimensions. Some have been seen whose size was five times that of the earth. They are generally surrounded by an aureola known as the penumbra, and sensibly less luminous than the other portions of the orb. From this penumbra, first observed by Galileo, many apparently singular deductions have been made: namely, 'The sun is a dark body, surrounded at a certain distance by an atmosphere which may be compared to that of the earth, when the latter is charged with a continuous stratum of opaque and reflecting clouds. To this first atmosphere succeeds a second, luminous in itself, called the photosphere. This photosphere, more or less remote from the inner cloudy atmosphere, would determine by its outline the visible limits of the orb. According to this hypothesis, there would he spots on the sun every time that there occurred in the two concentric atmospheres such corresponding clear spaces as would allow of our seeing the dark central body uncovered.'

This hypothesis is considered by the most competent judges to render a very satisfactory account of the facts. But it has not been universally adopted. Some writers of authority have lately represented the spots as scoriæ floating on a liquid surface, and ejected from solar volcanoes, of which the burning mountains of the earth convey but a feeble idea. Hence observations become necessary as to the nature of the incandescent matter of the sun; and when we remember the immense distance of that body, such an attempt may well appear to be one of temerity.

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