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To ADELAIDE PROCTER.
Thou dove, who tidings bring'st of calmer hours !
Thou rainbow, who dost shine when all the showers
Untouched, untainted! O my Flower of flowers !
Welcome - a thousand welcomes ! Care, who clings
New hope springs upward, and the bright world seems
Cast back into a youth of endless Springs ! Sweet mother, is it so ? or grow I old,
Bewildered in divine Elysian dreams?
COME, LET US GO TO THE LAND.
Where the violets grow!
There, in the beautiful south,
Where the sweet flowers lie,
Under the light of the evening sky,
RICHARD ANTHONY PROCTOR.
PROCTOR, RICHARD ANTHONY, a distinguished English astronomer; born at Chelsea, March 23, 1834; died at New York, September 12, 1888. He was graduated at St. John's College, Cambridge, in 1860, and devoted himself especially to the study of astronomy, and to elucidating its leading facts and principles, frequently in popular lectures. He visited America for this purpose several times, and in 1885 became a citizen of the United States. He had passed the summer of 1888 in Florida, where the yellow fever broke out with great violence, which he contracted, with fatal result. His practical work in measuring the rotation of Mars and charting the 324,198 stars of Argelander's catalogue is worthy of mention. Among his most important astronomical works are “ Saturn and its System” (1865); “ Handbook of the Stars” (1866); “Half-hours with the Telescope” (1868); “ Other Worlds than Ours” (1870); “Myths and Marvels of Astronomy” (1877); “Old and New Astronomy” (1888). He also put forth several works of a semiscientific character, among which are “Light Science for Leisure Hours," three series (1871, 1873, 1878); “The Great Pyramid;" “Observatory, Tomb, Temple” (1883); “How to Play Whist” (1885); “Chance and Luck” (1887); and numerous “Essays" upon miscellaneous topics.
JUPITER, THE GIANT OF THE SOLAR SYSTEM.
(From "Other Worlds than Ours.") PASSING over the zone of asteroids, we come now to the noblest of all the planets — the giant Jupiter. If bulk is to be the measure of a planet's fitness to be the abode of living creatures, then must Jupiter be inhabited by the most favored races existing throughout the whole range of the solar system. Exceeding our earth some one thousand two hundred and thirty times in volume, and more than three hundred times in mass, this magnificent orb was rightly selected by Brewster as the crowning proof of the relative insignificance of the earth in the scale of creation.
Or if we estimate Jupiter rather by the forces inherent in his system, if we contemplate the enormous rapidity with which his vast bulk whirls round upon its axis, or trace the stately motion with which he sweeps onward on his orbit, or measure the influences by which he sways his noble family of satellites, we are equally impressed with the feeling that here we have the prince of all the planets, the orb which, of all others in the solar scheme, suggests to us conceptions of the noblest forms of life.
The very symmetry and perfection of the system which circles round Jupiter have led many to believe that he must be inhabited by races superior in intelligence to any which people our earth. The motions of these bodies afford, indeed, to our astronomers a noble subject of study. Our most eminent mathematicians have given many hours of study to the phenomena which the four moons present to the terrestrial observer. But we can trace only the general movements of the satellites of Jupiter. Their minor disturbances, the effects of the varying influences which the sun and Jupiter exert upon them, and which the moons exert upon each other, must tax the powers of far abler mathematicians even than he who “surpassed the whole human race in mental grasp.”
But, after all, we must judge of Jupiter rather according to the evidence we have, and the analogies which are most directly applicable to the case, than according to fancies such as these. We know that the sun, which surpasses Jupiter in weight and volume even more than Jupiter surpasses the earth, is yet not the abode of life, so that mere size and mass must not be held to argue habitability. We know that many meteors and comets sweep through space more swiftly than the vast bulk of Jupiter, so that the energies indicated by mere velocity of motion, whether orbital or rotational, must be equally disregarded. Nor must we forget that, ages before men studied the motions of our own moon, she presented the same noble subject of study that she forms in our day for an Adams, a Leverrier, or a Delaunay. Even now a thousand grand problems are presented to our men of science which escape their notice, and we might as reasonably argue that there must be creatures existing unperceived among us, who deal with these problems, as that, out yonder in space, there must be beings who study the complicated motions of the Jovian satellites.
Jupiter presents the following principal physical habitudes:
He has a diameter of about eighty-five thousand miles, or nearly eleven times as large as the earth’s, a surface one hundred and fifteen times larger, and, as I have said, a volume more than one thousand two hundred times larger. Gravity at his surface is about two and a half times as great as on our earth's, so that such creatures as exist around us would find their weight much more than doubled if they were removed to Jupiter. He lies more than five times further from the sun than our earth, and the light and heat which he receives from that orb are reduced to about one-twenty-fifth of our supply. He rotates on his axis in rather less than ten hours (9 hours, 55 minutes, 26 seconds), so that the length of his day is considerably less than half of ours. His axis is nearly perpendicular to his orbit, so that there are no appreciable seasonal changes as he sweeps round the sun in his long year of 4,332) days.
It will be convenient to consider, first, the probable influence of the great attractive power of Jupiter upon the dimensions of the various orders of living creatures existing upon his surface.
The grandeur of his orb naturally suggests, at first sight, the idea of beings far exceeding, both in might and bulk, those which live upon the earth. Old Wolfius was led to a similar conclusion in another way. I quote his quaint fancies as quaintly presented by Admiral Smyth. 6 Wolfius,” says the genial sailor, “not only asserts that there are inhabitants in Jupiter, but also shows that they must necessarily be much larger than those of the earth ; in fact, that they are of the giant kind, and nearly fourteen feet high by eye-measurement. And thus he proves it. It is shown in optics that the pupil of the eye dilates and contracts according to the degree of light it encounters. Wherefore, since in Jupiter the sun's meridian height is much weaker than on the earth, the pupil will need to be much more dilatable in the Jovian creature than in the terrestrial one. But the pupil is observed to have a constant proportion to the ball of the eye, and the ball of the eye to the rest of the body; so that, in animals, the larger the pupil the larger the eye, and consequently the larger the body. Assuming that these conditions are unquestionable, he shows that Jupiter's distance from the sun, compared with the earth's, is as 26 to 5; the intensity of the sun's light in Jupiter is to its intensity on the earth in a duplicate ratio of 5 to 26." The eyes of the Jovians and their dimensions generally must be correspond
ingly enlarged, and “it therefore follows that even Goliath of Gath would have cut but a sorry figure among the natives of Jupiter. That is, supposing the Philistine's altitude to be somewhere between eight feet and eleven, according as we lean to Bishop Cumberland's calculation, or the Vatican copy of the Septuagint. Now, Wolfius proves the size of the inhabitants of Jupiter to be the same as that of Og, king of Bashan, whose iron camp-bed was nine cubits in length and four in breadth — or rather he shows, in the way stated, the ordinary altitude of the Jovicolæ to be 13-816 Paris feet, and the height of Og to have been 131228 feet. See his Works, vol. iii., p. 438."
This exact determination of the dimensions of Jovian men would be very pleasing and satisfactory were it not that another line of argument guides us at least as conclusively to a very different view. If we are to assume that beings resembling men in all attributes except size actually exist on Jupiter, we might claim for these beings the power of moving from place to place as freely as we do, with quite as much reason as Wolfius claimed for them the same powers of vision that we possess. Proceeding according to this view, we are led to the conclusion that the Jovicolæ are pygmies about two and a half feet, on the average, in height. For we know that a man removed to Jupiter would weigh about two and a half times as much as he does on our own earth. He would thus be oppressed with a burden equivalent to half as much again as his own weight. This would render life itself an insupportable burden; and we have to inquire what difference of size would suffice to make a Jove-man as active as our terrestrial men. Now, the weight of bodies similarly proportioned varies as the third power of the height; for example, a body twice as high as another – in other respects similar — will be eight times as heary. But the muscular power of animals varies as the cross-section of corresponding muscles, or obviously as the square of the linear dimensions; so that of two animals similarly constituted, but one twice as high as the other, the larger would be four times the more powerful. Ile would weigh, however, eight times as much as the other. He would therefore be only half as active. Similarly, an animal three times as high as another of similar build, would be only one-third as active; and so on for all such relations. Now, since a terrestrial man removed to Jupiter would be two and a half times as heavy as on the earth, it follows, obviously, that a man on Jupiter proportioned like our terres