THE BEAUTY OF THE HEAVENS.

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The upper figure of the scene represents that portion of the Milky way which traverses our hemisphere; the lower figure, a section through its sup-posed length. Our solar system is supposed to be in the centre ; and thelonger branches to be the direction of the brightest spots we see ; the shorterdistances the parts where there are fewest stars.

Scene No. LXXXI.— Clusters of Stars.

In the apparently unequal distribution of the stars, there are many whichseem nearly close together, and at equal distances from each other, withoutpossessing any determinate figure. These collections are called groups ofstars. There are other collections of stars which differ from these in thegreater beauty of their arrangement : these clusters are considered the mostmagnificent objects in the heavens ; their form is generally round ; and thewhole appearance of a cluster indicates the existence of a central power by whichthey are drawn, or held together. Herschel found, on examination of such clus-ters, that the number of stars in each often exceeded 300,000.

In the scene, we have examples of various modes of clustering. The firstfigure, on the left, is a thinly scattered cluster, of uniform arrangement ; in thesecond figure, a similar cluster is seen, in which the stars towards the centre aredrawn more closely together; in the third, two instances in which they are clusteredmore closely, and in a more determinate form ; in the fourth, the clustering takesa determinate figure, and becomes more dense as it approaches the centre ; thefifth figure is a space of circular form, which seems to be composed of starsclosely clustered together, and placed at an immense distance ; the sixth, andlast figure, is an instance of an appearance that frequently occurs—a brilliantcentral point, having a uniformly luminous atmosphere.

Scene No. LXXXII.— Nebulous Stars and Nebula:.

The appearances, termed nebulae, seem to be clusters of stars so distant, orso numerous, as to present the effect of a bright or luminous cloud. We haveaccurate catalogues of several thousands of these phenomena made from actualobservation. Of these, the scene gives examples of each variety. The firstfigure, on the left of the picture, is a close mass of stars, intermixed with afainter light; it presents the appearance of a solid sphere composed of stars,compressed into one blaze of light, with detached stars surrounding it. Thesecond figure is double ; the two parts appear to be composed of stars like thelast; they are of different degrees of brightness. The third figure, is an instanceof a single small and bright star, having close to it a luminous stripe, or ray.The fourth, is a very bright central figure of an oval form, and surrounded by aspace of mottled, or uneven light. The fifth figure is a portion of a larger