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crescent, when it should next appear, would be found. But in this he was disappointed; for when the moon became first faintly visible in the western sky, the group of stars which had ushered her in before had disappeared below the horizon, and a new group had taken its place; and thus it was discovered that each successive new moon fell farther and farther backward among the stars. By counting the days from new moon to new moon, and those which elapsed while the moon was passing round the heavens from a certain fixed star to this same star again, it was found that these two periods were different; the revolution from new to new occupying twenty-nine and a half days, while the sidereal revolution, from star to star, required twenty-seven one-third days.

This backward motion of the moon among the stars must have perplexed the early astronomers; and for a long while it was utterly impossible to decide whether the motion was real or only apparent. Analogy would lead to the conclusion that all motion must be in the same direction; and as the heavens revolved from east to west, it seemed impossible that the moon, which manifestly participated in this general movement, should have another and a different motion from west to east. There was one solution of this mystery, and I have no doubt it was for a long while accepted and believed. It was this. By giving to the moon a slower motion from east to west than the general motion of the heavens, she would appear to lag behind the stars, which would by their swifter velocity pass by her, and thus occasion in her the observed apparent motion from west to east. We shall see presently how this error was detected.

The long and accurate vigils of the moon, and the necessity of recognizing her place by the clusters or groups of stars among which she was nightly found, had already familiarized the eye with those along her track, and even thus early the heavens began to be divided into constellations. The eye was not long in detecting the singular fact that this stream of constellations, lying along the moon's path, was constantly flowing to the west, and one group after another apparently dropping into the sun, or at least becoming invisible, in consequence of their proximity to this brilliant orb. A closer examination revealed the fact, that the aspect of the whole heavens was changing from month to month. Constellations which had been conspicuous in the west, and whose brighter stars were the first to appear as the twilight faded, were found to sink lower and lower towards the horizon, till they were no longer seen; while new groups were constantly appearing in the east.

These wonderful changes, so strange and inexplicable, must have long perplexed the early student of the heavens. Hitherto, the stars along the moon's route had engaged special attention; but at length certain bright and conspicuous contellations towards the north arrested the eye; and these were watched to see whether they would disappear. Some were found to dip below the western horizon, soon to re-appear in the east; while others, revolving with the general heavens, rose high above the horizon, swept steadily round, sank far down, but never disappeared from the sight. This remarkable discovery soon led to another equally important. In watching the stars in the north through an entire night, they all seemed to describe circles; having a common centre, these circles grew smaller and smaller as the stars approached nearer to the centre of revolution, until finally one bright star was found whose position was ever fixed, alone unchanged while all else was slowly moving. The

discovery of this remarkable star must have been hailed with uncommon delight by the primitive observer of the heavens. If his deep devotion to the study of the skies had created surprise among his rude countrymen, when he came to point to his never-changing light hung up in the heavens, and explained its uses in guiding their wanderings on the earth, their surprise must have given place to admiration. Here was the first valuable gift of primitive astronomical science to man.

But to the astronomer this discovery opened up a new field of investigation, and light began to dawn on some of the most mysterious questions which had long perplexed him. He had watched the constellations in the moon's track slowly disappear in the effulgence of the sun; and when they were next seen, it was in the east, in the early dawn, apparently emerging from the solar beams, having actually passed by the sun. Watching and reflecting, steadily pursuing the march of the northern constellations, which never entirely disappeared, and noting the relative position of these, and those falling into the sun, it was at last discovered that the entire starry heavens were slowly moving forward to meet and pass by the sun, or else the sun itself was actually moving backward among the stars. This apparent motion had already been detected in the moon, and now came the reward of long and diligent perseverance. The grand discovery was made, that both the sun and moon were moving among the fixed stars, not apparently but absolutely. The previously received explanation of the moon's motion could no longer be sustained; for the starry heavens could not at the same time so move as to pass by the moon in one month, and to pass by the sun in a period twelve times as great. A train of the most important conclusions flowed at once from this great discovery. The starry heavens passed beneath and around the earth; the sun and moon were wandering in the same direction, but with different velocities among the stars; the constellations actually filled the entire heavens above the earth and beneath the earth; the stars were invisible in the day-time, not because they did not exist, but because their feeble light was lost in the superior brilliancy of the sun. The heavens were spherical, and encompassed like a shell the entire earth, and hence it was conceived that the earth itself was also a globe, occupying the centre of the starry sphere.

It is impossible for us, familiar as we are at this day with these important truths, to appreciate the rare merit of him who, by the power of his genius, first rose to their knowledge and revealed them to an astonished world. We delight to honour the names of Kepler, of Galileo, of Newton; but here are discoveries so far back in the dim past, that all trace of their origin is lost, which vie in interest and importance with the proudest achievements of any age.

With a knowledge of the sphericity of the heavens, the revolution of the sun and moon, the constellations of the celestial sphere, the axis of its diurnal revolution, astronomy began to be a science, and its future progress was destined to be rapid and brilliant. A line drawn from the earth's centre to the north star formed the axis of the heavens, and day and night around this axis all the celestial host were noiselessly pursuing their never-ending journeys. Thus far, the only moving bodies known were the sun and moon. These large and brilliant bodies, by their magnitude and splendour, 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 con

figurations, 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 sank below the horizon, the attentive watcher marked the bright stars near the point of setting which first appeared in the evening twilight. These gradually sank 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.

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While intently engaged in watching the sun as it slowly 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 upon the sun. 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 neighbouring stars. Night after night he gazes on this unprecedented phenomena, a moving star! and on each successive night he finds the wanderer coming nearer and nearer to the sun. last it disappears from sight, plunged in the beams of the upheaving sun. What had become of this strange wanderer? Was it lost for ever? 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 grey 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 investigation 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 so; 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.-Mitchell on the "Planetary and Stellar Worlds."

MISCELLANEOUS ARTICLES, ANECDOTES, &c.

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A MYSTERIOUS SHIELD IN THE DAY OF BATTLE. It was on one of those days of feverish excitement which, in 1798, spread such terror and dismay through the length and breadth of Ireland, that Adam Averell felt "pressed in spirit" to visit Monasterevan. It required no ordinary courage to venture from home at such a time, as the country was literally distracted, and his own little "villa," at Tentower, was still in ruins, having been attacked but a few days before by the "United Irishmen." Speaking of that assault he says, They forced the doors, broke open all my lockers, destroyed much of my furniture, took about seven cwt. of lead from the roof of the house (I suppose

to make balls), and cut about one hundred of my young ash trees, of course to make pike-handles." Yet in the face of all this devastation, and though perfectly aware of the danger to which he would be exposed by travelling abroad, mounted his horse and set out for Monasterevan. Nothing particular transpired by the way, but his reception at the end of the journey and the scenes which immediately followed, sufficiently accounted for that extraordinary impression" which

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led him to set out on such an errand of mercy.

In his own account of that visit, he says, Brother Fox's family were

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at dinner when I arrived; and, on my entering the dining-room, sister Fox, after an exclamation of surprise, burst into a flood of tears, and all the rest of the family were deeply affected. I stood in silent wonder, until sister Fox, having regained somewhat of her composure, said,

Mr. Averell, you are come to die with us!' On asking for an explanation, I was informed by brother Fox that a priest who had been taken prisoner, and from whom secret information had been extorted by flogging, had stated that the rebels, from their encampment on the Curragh of Kildare, were that night to attack the town. I then inquired what force there was to repel them, and he told me there were of soldiers, yeomen, and Protestants, only about eighty men. 'Of these,' continued he, ten are pious young men belonging to our (Methodist) Society, who were formerly enrolled amongst the yeomanry; but as they would not violate the Sabbath by unnecessarily joining in military exercises on that day, they were deprived of their arms. On their making an offer of their services for the defence of the town to-day, and requesting to be supplied with arms, they were abused as men whose loyalty could not be depended on, as they had withdrawn from the yeomanry, and the arms were refused. A second application, however, was more successful: the commanding-officer declaring, with a tremendous oath, that they should be stationed where they would get their courage tried. They are, added brother Fox, 'placed under the direction of a steady, religious man of the name of Johnston, who was a sergeant in the army, and he is at present drilling them in an adjoining field.' I now proposed, as it was probable we might never have another opportunity, that we should have preaching; which having been announced, we had a large congregation; and seldom did any people ever before meet under similar views and apprehensions to worship God. It was a solemn assembly; and we had a deeply solemn and affecting time in waiting upon the Lord. Sergeant Johnston and his party at

tended, but kept at the door with their bayonets fixed, as they knew not the moment their services might be required. Nothing, however, interrupted us: we concluded in peace, and parted as if we were to meet no moré in this world.

"After returning to brother Fox's, and committing ourselves to the care of Him who never slumbers nor sleeps, I retired to bed; but the family, or most of them, remained up. I slept until I was awoke by the sun beaming strongly in my face a little before five o'clock in the morning, and arose with a heart truly thankful to Him who had been my preserver throughout the night. While dressing, I was suddenly enveloped in a thick gloom: a dense fog had arisen, which so obscured the sun that objects only a few yards distant could not be discerned; and soon after were heard volleys of firing. Brother Fox coming into my room, informed me the engagement had commenced, and begged me to come to the parlour, as the family were in great confusion. I felt for a moment a sensation of alarm; but having told him to go down, and I would soon follow, I fell on my knees in prayer; and my ever-gracious God so filled my soul with his peace, that all my fears subsided, and I could with unwavering confidence commit myself to his care. On joining the family, I requested that the windows might be closed, and we went to prayer, brother Fox and I praying alternately. Nor did we seek God in vain. We had blessed indications of his gracious presence, and I felt it strongly impressed on my mind that he would be on this occasion our shield and our defence. We continued in prayer for about an hour and a half, when, after rising from our knees, a pious servant-maid of the family opened one of the windows to look out, and breathlessly exclaimed,The battle's won. I see a yeoman throwing up his cap into the air!' We all got to the windows, and soon saw that it was so; that God had given us the victory! Our chief concern now was about sister Dennis and the inmates of her establishment. This lady kept a boarding-school in the town, and had

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