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looked up with a sudden flush; she had scarcely ever heard him name Charley's name, since his last letter came.
They had a quiet wedding; a few friends of Colonel Hermance, the father, and Rose. Pure and delicate, Mary looked in her simple bridal dress, with rose-buds in her braided her. 'More beautiful to me than even the Mary Wilmerdings of old,' Colonel Hermance had whispered, as she came from her chamber to join him, just before the ceremony. The guests went away early with the clergyman, leaving the family to themselves. The room was very quiet, a faint scent of roses everywhere. The two were happy-so was the little child. The father sat apart, a mist gathering in his eyes; while his thoughts went back into the past, one hot tear fell upon his
hand. The door stood open which led to the kitchen, where the tall old clock was ticking in the silence. The door leading in from the porch opened with a sharp click as the latch fell. Stepsheavy, uneven, came through the kitchen. 'Some of the guests must have forgotten something,' thought Mary. A tall figure stooped to enter the low doorway; the group stared at the intruder. 'Don't you know me? Father! Mary! I've written, but I was in prison; perhaps my letters didn't come! I escaped at last. O father! father!' and he knelt down before the old man. The gray head was bowed over the dark curls; the father's heart sang 'Te deum laudamus;' the lost was found, the dead was alive again. For it was Charley.
PROVINGS OF CURRENT THEORIES IN SCIENCE.
Lunar Origin of Meteoric Stones.
LAPLACE, in support of his doctrine that meteoric stones have their origin in lunar volcanoes, calculated that the projectile force necessary to throw them without the moon's sphere of attraction within that of the earth, would be only about four times that of a ball from a
To find the diameter of the moon's sphere of attraction, compared with that of the earth's sphere, say as the moon's mass (1) is to the earth's mass, (80,) so is the square of the diameter of the moon's sphere (x2 miles) to the square of the diameter of the earth's sphere, ([two hundred and forty thousand-x] miles,) making the diameter of the moon's sphere twenty-four thousand miles. It would require many thousands of times, instead of only four times, the force of a cannon-charge to hurl so far stones of the weight of some
that have fallen. Of course it will not be presumed that any volcano upon the moon is capable of giving such a force. In the March and May numbers of Silliman's Journal of Science for 1855, Professor J. Lawrence Smith has an elaborate and very interesting memoir advocating the lunar theory. The Professor seems not to have examined for himself 'the difficulty that there appears to be in the way of the moon's projecting masses of matter beyond the central point of attraction between the earth and herself,' but to have, instead, relied for decision in the case upon Laplace, who, he says, with all his mathematical acumen, 'saw no difficulty, although we know he gave special attention to it at three different times during a period of thirty years, and died without discovering any physical difficulty in the way.' We think no one, not even Professor
Smith, will question the correctness of our calculation indicating the volcanic force necessary to project a stone thus beyond the lunar influence, nor hesitate to conclude with us that there never could have been a volcano upon the moon capable of supplying so great a force. Then we might take for granted that there is already a verdict declared against the claim that meteorites do at all originate at our satellite. However, we offer for consideration one other point of objection to the Professor's claim.
It is an axiom that the whole of a thing is greater than any one of its parts. So it is a truth, which is fully entitled to be received as axiomatic, that the undivided power of any self-controlling machine cannot be overcome by whatever power may be brought to bear by any separate part of the same machine. For instance, no man is able to lift his whole person by the force, acting directly, of one of his arms. Neither can a wheel, which is revolving in a certain direction, beneath the pressure of a column of water, be made to turn in an opposite direction by half of the same column falling back upon it from a height equal to the height from which the whole is falling. Neither is it possible to bring together, and to bear, the elements of the largestpower existing in any portion of our earth, even though this portion should consist of all the powderproducing materials capable of being gathered from the entire face and bowels of the globe, and of the whole circumambient atmosphere whirled into a tornado, and of all earth's fires, external and internal, surging forth in one mighty volcano. Neither is it possible to bring to bear the elements of power existing in any such portion of the earth, so as to carry a mass of matter - whether a bullet, or a stone, or any other-outside of the influence which the whole earth exerts upon it to hold it in her embrace, nor so as to give it a motion away from the earth swifter than the motion with which it rotates as a part of the rotating
earth. So it is an impossibility—an impossibility such as contradicts the very laws of thought-that the moon should, by any force or any combination of forces she can ever generate, cast a meteorite beyond the influence which has served to bind it to her, be this influence great or small.
A word, in passing, touching the following passage from Professor Smith's memoir: 'No mention will be made of the phenomena accompanying the fall of meteorites, since the omission will affect in no way the theoretical views under consideration.'
One of these 'phenomena' is the direction--whether forward with, or contrary to the earth's rotation in which the meteorites pass while falling. In order to show them to have had a lunar origin, it is indispensably necessary to show also, first, that the direction of each meteorite is the same with that of every other; secondly, that no one meteorite ever changes its course before reaching the earth. Then the Professor's omission does affect most essentially his theoretical views.
How is it with regard to the two points named? Certainly, no one will be presumptuous enough to attempt a maintenance of the first; for all the facts are against it. The second will be disposed of differently, according to the difference in the preconceived opinions of those who take it upon themselves to decide in the case, some receiving for testimony what others would throw out as not to be depended upon fully. For ourselves, we incline to the belief that the directions of meteorites may be, and are sometimes, changed, partially at least; and we rely for evidence mainly upon Professor Upham Shepard's Report on Meteorites, referred to in the memoir under notice. It appears from that Report that the stone which was found to have struck the south-western side of a tree in Little Piney, Missouri, had been observed at Potosi, eighty miles east of Little Piney, moving westerly, indicating
its route to have been along circuitous atmospheric currents, rather than direct from the moon.
Suppose it possible for a lunar volcano to throw a stone beyond the line dividing the moon's and the earth's attractions—namely, a line twenty-four thousand miles distant from the moon. The stone, in rising to such height, then in falling through the remaining distance which the moon and earth are apart, (two hundred and sixteen thousand miles,) would take three hours, (according to the law of falling bodies namely, the law that a body will fall sixteen feet during the first second, three times sixteen feet during the second second, five times sixteen feet during the third second, and so on,) gaining by its fall (according to the same law) a velocity of one hundred and eighty-four thousand miles per hour. The moon passes in her orbit at the rate of twentytwo hundred miles per hour, which rate of motion the stone would carry with it in its departure, receiving thus a direction, not in a right line towards the centre of the earth, but in advance of this line, so that, at the expiration of the three hours, it would be sixty-six hundred miles forward of the earth's centre. Now, with the projectile force imparted to it by a speed of one hundred and eighty-six thousand miles per hour that acquired in falling, united with that received from the moon it could not, upon the principle of the Newtonian theory, come to the earth at all, but must revolve about her in an orbit so elliptical as to have its apogee a million miles farther outward than that of the moon's orbit, while its perigee would be two hundred and thirty-three thousand four hundred miles farther inward than that of the moon's orbit.
The diameter of the moon's sphere of attraction, compared with that of the sun's sphere, is less than it is, compared with that of the earth's sphere. As the moon's mass (1) is to the sun's mass,
(twenty-eight millions,) so is the square of the diameter of the moon's sphere (x2 miles) to the square of the diameter of the sun's sphere, ([ninety-five millions-x] miles,) making the diameter of the moon's sphere eighteen thousand miles, only three fourths of what it is, reckoned in relation with the diameter of the earth's sphere. Then, a stone cast from the moon beyond the limit of her attraction, whether this limit be distant the eighteen thousand or the twenty-four thousand miles, would seek, not the earth, but the sun, as its centre of gravity. The earth could not govern it, unless when in a line between it and the sun, or when so near such line that it would, in passing, intersect the line bounding her sphere of attraction. In order to this, the stone must come from the moon at or very near the time of her full.
The moon, in her passage with the earth round the sun, has an average velocity of sixty-eight thousand miles per hour. So a stone, sent from one of her volcanoes within the sun's attraction, would have a speed of sixty-eight thousand miles per hour, which would make its path a curve forward of the sun, instead of a straight line cutting his centre. It would be fifty hours in falling through the distance of ninety-five million miles, at the end of which time it would be at a point three million miles away from the sun's surface, having a velocity of thirty-eight thousand miles per hour. Such velocity would give it an hundred times the projectile force-(this force being as the square of the velocity)—an hundred times the projectile force needed, according to the gravitation doctrine, to retain it in a planetary orbit. So it must be driven into a cometary orbit one so elliptical as to have its aphelion three hundred and fifty million miles from the sun's centre-further outward than the orbit of the outermost asteroid; while its perihelion would be not three million five hundred thousand miles from the same centre, as shown already.
Query: Whether our little, modest matron of a moon is not the mother of the comets, after all?
Suppose a stone to have fallen out of the earth's orbit—that is, from the moon revolving with the earth-into an orbit of its own about the sun. It was fifty hours in falling, which time, multiplied by the hourly velocity of its passage while a part of the moon, is the measure of the distance from the sun's centre forward to the point where its descent from its old annual path terminated, and where its new annual path commenced. A line from this point forms, at the centre of the sun, a right angle with a line from the point at which its descent began; so that, when it started in its new course, (from the perihelion point of its orbit,) it was one quarter of the whole circle of the zodiac in advance of the position which it left in its original course. The breadth of its new orbit, also, is measured by its velocity in its old orbit multiplied into the time occupied in falling therefrom, being twice the length of its perihelion line-that is, seven million miles. The elongation of this orbit is measured by the stone's excess of projectile force above what was needed, according to the Third Law of Kepler, to balance its excess of gravitating force obtained by its near approach to the sun. Kepler's law increases the velocity of a body revolving about the centre of gravity in proportion to the square root of the distance towards that centre passed through by the body. Thus, the stone in the earth's orbit ninety-five million miles from the sun - had a velocity of sixtyeight thousand miles per hour; then its velocity in an orbit three million five hundred thousand miles from the sun will bear the same proportion to the other, as the square root of the latter distance bears to that of the former distance, making the new velocity three hundred and fifty thousand miles per hour. The projectile force imparted to the stone by this additional speed-being according to the square of the speed
-was sufficient to cancel its increase of gravity produced by its fall, and to direct it into a circular orbit seven million miles in diameter. But it acquired, in falling, ten times the speed — three million eight hundred thousand miles per hour-therefore an hundred times the projectile force; by means of which force the orbit was lengthened from seven million to three hundred and fiftythree million five hundred thousand miles, taking thence the shape of a parallelogram with its ends rounded, rather than that of a regular planetary ellipse. The circumference of such an orbit is equal to that of a circular one of two hundred and forty million miles in diameter; and the stone, governed by Kepler's law, (that is, decreasing its speed of three million eight hundred thousand miles per hour, at three million five hundred thousand miles distance from the sun's centre, according to the distance which it passes outward to reach its aphelion,) performed a revolution in this orbit in forty-six days, crossing the earth's path both on its course outward and on its return inward. The distance, in a straight line, between these two points of crossing, is seven million miles. The earth, at the time of the stone's departure from her orbit, wanted half this distance of being three quarters of the extent of her circuit behind the first of those points; then she will reach it at the expiration of two hundred and seventy-two days from that time, when the stone will lack six days of having completed its sixth revolution, and will be a day and an half's journey behind the other point of intersection. By the time of its arrival at the latter point, the earth will have passed along her orbit to within four or five million miles of it, at which position the stone, supposing it to be partially vaporized, therefore enlarged, by the heat to which it is subjected in its near and frequent approaches to the sun, as is supposed of the comets, might be seen as a 'shooting star,' moving in the direction of the earth's movement on her axis. The
earth, in her second subsequent revolution, will have passed the same crossingpoint two or three hundred thousand miles when the stone has arrived there in its twenty-first revolution; so that this will be seen shooting in a direction contrary to that of the earth's rotation. Now, allowing for the deviations from a direct line to which the stone must be
subject in its passage among the planets and asteroids, it might come so near the earth, in the second case especially, as to fall a meteorite into her embrace. Question: Whether we shall not be claimed as supporters of the Lunar Theory, notwithstanding our demon-. strations of its falsity?
'As that new grave was covered, the beauty of a sunset of extraordinary splendor was poured over it as a last farewell; and as the sun went down over the Rockland Hills, and the gold of the clouds faded into gray, and the glory of the rolling river died in the leaden dulness of the night, there were few of the thou sands returning homeward from that day's pilgrimage whose hearts were not moved within them.'--Paper of the day.
THEY have laid him at rest, and that sun-gilded hill
At whose base his loved Hudson rolls sparkling and still,
Is his monument now, and his pillow its sod,
As that river, his life-stream flowed tranquil and kind,
They have laid him at rest, and his spirit has fled,
Rear o'er him no column, no vainly-carved stone,
In the scenes he has pictured is mirrored his fame
Shall scroll his loved name, on his own native land,
And his beautiful grave tell his story.
IRVING'S BIRTHDAY, April 5.
C. W. L.