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their never ending journies.—Thus far, the only moving bodies known, were the sun and moon. These large and brilliant bodies, by their magnitude and splendor, stood out conspicuously, from among the multitude of stars, leaving these minute but beautiful points of light, in one great class, unchangeable among themselves, fixed in their groupings and configurations, furnishing admirable points of reference, in watching and tracing out the wanderings of the sun and moon.
To follow the moon as she pursued her journey among the stars was not difficult; but to trace the sun in his slower and more majestic motion, and to mark accurately his track, from star to star, as he heaved upward to meet the coming constellations, was not so readily accomplished. Night after night, as he sunk below the horizon, the attentive watcher marked the bright stars near the point of setting which first appeared in the evening twilight.— These gradually sunk towards the sun on successive nights, and thus was he traced from constellation to constellation, until the entire circuit of the heavens was performed, and he was once more attended by the same bright stars, that had watched long before, his sinking in the west. Here was revealed the measure of the Year. The earth had been verdant with the beauties of spring,-glowing with the maturity of summer,-rich in the fruits of autumn,-and locked in the icy chains of winter, while the sun had circled round the heavens. His entrance into certain constellations marked the coming seasons, and man was beginning to couple his cycle of pursuits on earth with the revolutions of the celestial orbs.
While intently engaged in watching the sun as it blowly heaved up to meet the constellations, some ardent devotee to this infant science, at length marked in the early twilight a certain brilliant star closely attendant
the The relative position of these two objects was noted, for a few consecutive nights, when with a degree of astonishment, of which we can form no conception, he discovered that this brilliant star was rapidly approaching the sun, and actually changing its place among the neighboring stars,— night after night he gazes on this unprecedented phenomenon, a moving star! and on each successive night he finds the wanderer coming nearer and nearer to the sun.
At last it disappears from sight, plunged in the beams of the upheaving sun. What had become of this strange wanderer ? was it lost forever? were questions which were easier asked than answered. But patient watching had revealed the fact, that when a group of stars, absorbed into the sun's rays, disappeared in the west, they were next seen in the eastern sky, slowly emerging from his morning beams. Might it not be possible, that this wandering star would pass by the sun, and re-appear in the east ? With how much anxiety must this primitive discoverer have watched in the morning twilight ? Day after day he sought his solitary post, and marked the rising stars, slowly lifting themselves above the eastern horizon. The gray dawn came, and the sun shot forth a flood of light, the stars faded and disappeared, and the watcher gives over, till the coming morning. But his hopes are crowned at last. Just before the sun breaks above the horizon, in the rosy east, refulgent with the coming day, he descries the pure white silver ray of his
long lost wanderer. It has passed the sun,-it rises in the east, the first planet is discovered!
With how much anxiety and interest did the delighted discoverer trace the movements of his wandering star. Here was a new theme for thought, for observation, for investigation; would this first planet sweep round the heavens, as did the sun and moon ? would it always move in the same direction ? would its path lie among those groups of stars among
which the sun and moon held their course ? Encouraged by past success, he rejoicingly enters on the investigations of these questions. For some time the planet pursues its journey from the sun, leaving it farther and farther behind. But directly it slackens its pace,
-it actually stops in its career, and the astonished observer, perhaps thinks that his wandering star had again become fixed. Not 80,-a few days of watching dispels this idea. Slowly at first, and soon more swiftly, the planet seeks again the sun, moving backwards on its former path, until finally its light is but just visible in the east at early dawn. Again it is lost in the sun's beams for a time, and contrary to all preceding analogy, when next seen, its silver ray comes out pure and bright, just above the setting sun. It now recedes from the sun, on each successive evening increasing its distance, till it again reaches a point never to be passed -here it stops—is stationary for a day or two, and then again sinks downward to meet the sun. How wonderful and inexplicable the movements of this wandering star must have appeared in the early ages! oscillating backward and forward, never passing its prescribed limits, and ever closely attendant upon the sun. Where the sun sunk to repose, there did the
faithful planet sink, and where the sun rose, at the same point did the wandering star make its appearance. The number of days was accurately noted, from the stationary point in the east above the sun, to the stationary point in the west above the sun, and thus the period, 584 days, from station to station, became known.
The discovery of one planet, led the way to the rapid discovery of several others. If we may judge of their order by their brilliancy, Jupiter was the second wanderer revealed among the stars. Then followed Mars, and Saturn, and after a long interval Mercury was detected, hovering near the sun, and imitating the curious motions of Venus.
Here the progress of planetary discovery was suddenly arrested, keen as was the vision of the old astronomer, long and patient as was his scrutiny, no depth of penetration of unaided vision could stretch beyond the mighty orbit of Saturn, and the search was given over.-A close examination of the planets revealed many important facts. Three of them, Mars, Jupiter, and Saturn, were found to perform the circuit of the heavens, like the sun and moon, and in the same direction, with this remarkable difference, that while the sun and moon, moved steadily and uniformly in the same direction, the planets occasionally slackened their pace, would then stop, move backwards on their track, stop again, and finally resume their onward motion. Their periods of revolution were discovered by marking the time which elapsed, after setting out from some brilliant and well known fixed star, until they should perform the entire circuit of the heavens and once more return to the same star. The times of
revolution were found to differ widely from each other; Mars requiring about 687 days, Jupiter 4,332 days, and Saturn 10,759 days, or nearly thirty of our years.
The planets all pursued their journics in the heavens, among the same constellations which marked the paths of the sun and moon, and hence these groups
of stars concentrated the greatest amount of attention among the early astronomers, and became distinguished from all the others.
Whatever light may be shed upon antiquity by deciphering the hieroglyphic memorials of the past there is no hope of ever going far enough back, to reach even the nation, to which we are indebted for the first rudiments of the science of the stars.
Thus far in the prosecution of the study of the heavens, the eye and the intellect had accomplished the entire work. Rapidly as we have sketched the progress of early discovery, and short as may have been the period in which it was accomplished, no one čan fail to perceive, how vast is the difference be tween the light that thus early broke in upon the mind, heralding the coming of a brighter day, and the deep and universal darkness which had covered the world, before the dawn of science. Encouraged by the success.which had thus far rewarded patient toil, the mind of man pushes on its investigations deeper and deeper into the domain of the mysterious and unknown.
In watching the annual revolution of the sun among the fixed stars, one remarkable peculiarity had long been recognized. While the interval of time, from the rising to the setting of the stars, was ever the same