MARS.

Mars is the next planet to receive our attention. It is the first of the superior planets; and by superior, we mean, that its orbit lies outside the orbit of the Earth, thus enabling us to see it at opposition of 180 degrees from the Sun.

Mars, called by the ancients the "god of wars," is a small planet, being a little less than 5,000 miles in diameter. It is the smallest of the superior planets, barring, of course, the Asteroids or telescopic planets, and has a red color.

The seasons on Mars are said to be similar to our own; with this difference, their year is longer. They have snow and rain, summer and winter, and they also have land and water, oceans and continents, as we have here.

Mars rotates on its axis in 24 hours and 37 minutes, and accomplishes a revolution round the Sun in about six weeks less than two years.

THE ASTEROIDS.

The Asteroids, or minor planets, consist of a zone of small telescopic planets lying between the orbits of Mars and Jupiter. Up to a few years ago, over 160 of them had been discovered, but there are, no doubt, many more. The largest of these planets are from 200 to 60 miles in diameter, and the periods of their revolution round the Sun varies from about three to six years.

It is supposed by some astronomers that these were formerly a planet, and that the planet, through some mishap-perhaps struck by a comet-was shattered in pieces. Of course, these pieces would float in the same zone that was occupied by the planet, and hence, would exist as a number of small planets. It is doubtful, however, if these were ever united in one body as we shall see later on.

JUPITER.

From that region of space where we have just seen the smallest of our system circulating in their orbits, we pass to the largest planet-the colossal Jupiter.

To the naked eye Jupiter appears as a star of the first magnitude, the brightness of which, variable with its distance from the Earth, is sometimes, when the Moon is absent, sufficient to throw shadows. Its light is constant, and scintilates but rarely. But if, to examine it, a rather powerful telescope is used, the point expands into a well defined disc, and is generally seen to be accompanied by three or four points of light, which oscillate in short periods of time round the central planet; these are the satellites of Jupiter.

Until recently Jupiter was supposed to have only four satellites, but on September 9, 1892, Professor Bernard, at the Lick Observatory, California, discovered a fifth satellite. This satellite is very small and its orbit lies very close to the planet. Two more satellites of Jupiter have been discovered recently.

This giant planet is over 85,000 miles in diameter, or about 1,300 times as large as the Earth; so large is Jupiter, in fact, that to make a tour of the planet, following the line of the equator, we would have to travel a distance of about 268,000 miles.

But notwithstanding the immense size of Jupiter, it is the most active of the planets, so far as its rotation is concerned; the planet turns on its axis in about ten hours.

Jupiter possesses a quality which is not common to the other planets; the planet is partly self-luminous. The mean distance of Jupiter from the Sun is 475,693,000 miles, and it requires twelve years to make a revolution around the Sun, thus traveling through space at a rate of about 29,000 miles an hour.

SATURN.

If Jupiter be the largest planet in our system, Saturn is by far the most beautiful. Saturn is the most gorgeously attended among the secondary systems of which that system itself is composed. Not by five only, but by even eight satellites, is the central planet encircled; and if these eight moons in their revolutions do not give rise to eclipses as frequently as do those of Jupiter, the inhabitants of Saturn possess a much stranger spectacle-one, as far as we know, unique in the planetary system.

I allude to the wondrous ring system which surrounds the planet at some distance from its equator, and revolves eternally round it.

Some of these rings shine with a golden light, brighter than the planet itself, while others are transparent. We know now that surrounding Saturn, and nearly in the plane of its equator, is extended a system of rings, which may be broadly divided into three, of unequal breadths; of these the thickness is relatively very small.

The exterior ring, the one farthest from the planet, is separated from the intermediate one by a very distinct break, whilst the interior ring, that nearest to Saturn, seems joined onto the second. Their brightnesses are very different; the intermediate ring, the most brilliant of the three, is more luminous than the globe of Saturn; the exterior ring is of a grayish tint, nearly of the same shade as the dark bands of the disk. Both of these are opaque, and throw on Saturn a very distinct shadow. The interior ring, on the contrary, is dusky, and almost of a purple tinge, and transparent; it stands out on the globe of Saturn as a dark band, through which the luminous disk is readily seen.

The exterior diameter of the outer ring is 166,920 miles; its breadth is nearly 10,000 miles. The breadth of the middle or bright ring is 17,600 miles; and the inner, transparent ring is 8,700 miles wide. From the surface of the planet to the inner edge of the ring system is 9,750 miles. So if we add 1,700 for the space between the outer and middle rings, it would give a grand total of 47,750 miles from the surface of the planet to the outer edge of the ring system.

Saturn turns on its axis in ten and one-half hours, and requires nearly thirty years to complete a revolution round the Sun.

The mean diameter of Saturn is about 70,100 miles, or 746 times larger than the Earth.

Notwithstanding the immense size of Saturn and its ring system, it is so far away, being 872,137,000 miles, that it only shines as a star of the first magnitude.

SATURN AND SUBLIMITY.

Some take the ocean for their ideal of sublimity, while others take the Sun; but give me Saturn and his wonderful system of rings and satellites.

The movements with which we are acquainted on the Earth can give us no idea of the spectacle produced by Saturn, a huge ball 70,000 miles in diameter, traveling through the depths of space with a velocity of 21,000 miles an hour. But suppose we could be placed stationary in space, say at a distance of 100,000 miles from Saturn, so that we could take in, as in a bird's-eye view, the wonderful scene—a broadside view of this monster planet as it came thundering past twenty times faster than a cannon ball! Add to this its glorious system of 167,000 miles of rings, shining out in their golden light, reflecting their tints and shades and purple hues, illuminating the whole scene of this grand panorama in the most magnificent splendor! Though these rings never touch the planet, they are, nevertheless, held in place and carried with him as if by an effort of his supreme and mighty will! Add again his satellites, revolving round him with the regularity of clock-work, as he plunges onward through space for ever. Such a sight, I believe, would be the most grand and wonderful! Sublime! that can be met with anywhere within

the confines of our solar system.

URANUS.

The Solar System, as known to the ancients, comprised all those celestial bodies the movements of which we have just studied, with the exception of the telescopic planets and the satellites of Saturn and Jupiter. A little over a century ago the number of planets remained the same as for ages past, and the confines of the system did not extend beyond Saturn. It was reserved for one of the most illustrious observers of modern times, Sir William Herschel, to double the radius of the sphere which embraces the bodies subject to the attraction of the Sun, by the discovery of a new planet-Uranus.