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Venus, Earth with its moon, Mars with two moons, Jupiter with five, ringed Saturn with eight, Uranus with four, Neptune with one, as far as we know at present, and nearly 300 discovered minor planets or asteroids, its meteor belts, probably hundreds, nay it may be thousands in number, of which seventy-six at least follow well-marked tracks; and its own peculiar and its visitant cometsso each of these star-suns has a similar system. Sixty million sun systems! All these belong to the universe which we call "ours. "How many other universes are fulfilling the Creator's purpose in illimitable space, human knowledge knows not. We can only bow in reverence and wonder before the mysteries of our own grand system.
THE SUN'S SIZE.
We start from the fact that our sun is a star. Its relative brilliancy is owing to the circumstance that it is the nearest star to us. We get twenty thousand million times more light from the sun than we do from Vega, the first magnitude star in constellation Lyra; but then Vega is more than a million times further removed from us than is the sun. Although our sun outmeasures all the stars in size to the naked eye, it is not by any means a large star, compared with others. Sirius, the Dog Star, so glorious a sight in the winter's sky, would be equal in bulk to nearly 600 suns such as ours if we only assume his light to be no more brilliant than our sunshine.
What curious estimates we hear of the apparent size of the sun! One compares it to a plate, another to something else. A dime held close to the eye will cover the disk. The astronomical measurement is the best. Its apparent diameter as seen from the earth is, at the maximum, about 321⁄2 minutes of a degree; at the minimum, about 311⁄2 minutes of a degree, the latter the ninetieth part of the distance from the horizon to the zenith. As there are 60 minutes to the degree, it would take less than 180 suns to reach from the zenith to the horizon. As the moon's diameter in telescopic measurement is about 31 minutes of a degree, there is not much difference in the apparent size of the sun and the moon.
"The apparent enlargement of the sun and moon near the horizon is an optical illusion, connected in some measure with the atmosphere, of which various expla
nations have been made since the time of Ptolemy. According to the ordinary laws of vision, the celestial bodies, particularly the moon, which is nearest the earth, ought to appear largest in the meridian (that is, due south and at the highest elevation), because their distance is then less than when they are near the horizon; yet daily experience proves that the contrary takes place.
"To an observer the visual angle subtended by the moon in the horizon is somewhat less than that under which she appears in the zenith; and this fact, a consequence indeed of her circular motion, is proved by accurate measurements of her diameters in those circumstances by the micrometer. The mean apparent diameter of the moon, at her greatest height, is 31 minutes in round numbers, but in the horizon she seems to the eye two or three times larger. The commonly received explanation of this phenomenon was first given by Descartes, and may be stated as follows:
"The opinion which we form of the magnitude of a distant body does not depend exclusively on the visual angle under which it appears, but also on its distance; and we judge of the distance by a comparison with other bodies. When the moon is near the zenith there is no interposing object with which we compare her, the matter of the atmosphere being scarcely visible. Deceived by the absence of intermediate objects, we suppose her to be very near.
"On the other hand we are used to observe a large extent of land lying between us and objects near the horizon, at the extremity of which the sky begins to appear; we therefore suppose the sky, with all the objects which are visible in it, to be at a great distance. The illusion is also greatly aided by the comparative feebleness of the light of the moon in the horizon, which renders us in a manner.sensible of the interposition of the atmosphere. Hence the moon, though seen under nearly the same angle, alternately appears very large and very small."
DIMENSIONS OF THE SUN.
What is true of the moon here is also true of the sun, and yet many persons will not be convinced that the sun does not appear to be larger when he is setting than at mid-day.
It would be impossible in such an article as this to give the methods by which
astronomers have arrived at the true dimensions of the sun. We must simply take their results. Its distance from side to side, that is, its diameter, is 865,000 miles. Its circumference, therefore, will be about three and one-seventh times that number. The diameter of the earth is 7916 miles, and its circumference, roughly speaking, 25,000 miles. These figures convey but indefinite ideas by themselves. We were amused, no doubt, by the romance "Round the Earth in Eighty Days," and "globe trotters" have put the romance into practice and fact. If a railroad were laid down round the earth, and an express train traveled day and night, at 60 miles an hour, the journey would require nearly 17 days. Under the same circumstances, five years would be required for the journey round the sun. And these dimensions are, irrespective of the atmosphere which extends some hundreds of thousands of miles beyond the sun's disk.
As compared with the earth in volume, it would take 13,000,000 earths to make up the sun in volume. Volume for volume, the earth weighs heavier than the sun. Any volume of the sun's matter weighs only a fortieth of the same volume of the matter composing the earth; so that, although it would take 13,000,000 earths to make up the bulk of the sun, it would take only 330,000 earths to make up the sun's weight.
If we were transferred with our present physical powers to the sun's surface, we should experience some curious sensations. Owing to the force of gravity there, pulling out our watches would be like lifting five or six pounds here. Only by a gigantic effort could we get our hands to our heads. We might stand up for a moment, if we had a wall to lean against; but if we got down to the surface, it would be a question whether we should be able to rise. On the earth's surface a stone starting from rest falls through 16 feet during the first second. On the sun such a stone would fall through 441 feet, for the force of gravity there is more than 271⁄2 times what it is here.
DISTANCE OF THE SUN.
The method of finding the distance of the sun is easily understood, although the details and intricacies of the working out of the problem can only be appreciated by the expert mathematician. The principle mainly followed hitherto is that of the
well-known proposition, in the Sixth Book of Euclid's Elements, which tells us that the sides of similar triangles are proportional. The similar triangles, in this instance, are constructed from observations on the transit of planets across the sun's face. Hence the deep interest which has been taken in the transits of Venns, which were supposed to offer the best facilities for the measurement. The results, however, do not satisfy astronomers. Those of the transit of 1869 gave the distance of the sun as 95,000,000 miles; those of 1874, 93,000,000 miles; those of 1882, 92,700,000 miles. As the next transit does not take place until June 8, A. D. 2004, it is probable that other, and, perhaps more definite methods will test, it may be correct, this estimate.
But what notion can we get from the bare figures expressing such a distance? Our minds fail to grasp it. A clock ticks once a second. It must tick three years without intermission to tick off the number of miles which separate the earth from the sun. Suppose our express train, at sixty miles an hour, traveled incessantly on the journey to the sun, it would take about a hundred and seventy-six years to complete it. If the "Father of his Country" had started off on such a tour on July 4, 1776, he would, if endowed with longevity, arrive at his destination in A. D. 1952. Yet light makes the journey in a little over eight minutes.
In measuring the distance of inaccessible terrestial objects we take a base line a few yards in length. In measuring the sun's distance by a transit of Venus, we take the earth's diameter, 7,916 miles, as our base line. For the purpose of measuring the distance of the stars we use twice the sun's distance from the earth, that is, the diameter of the earth's orbit. That is the measuring staff, and yet it is all too small!
ROTATION OF THE SUN.
The sun rotates on its axis, like the earth. The earth's rotation is completed in 23 hours, 54 minutes, 56 seconds. The exact time occupied by the sun is at present uncertain. This rotatory motion is proved by the appearance and disappearance of spots on the sun's face. These spots always appear on the same side, move across the disk and disappear on the opposite side, to appear again as before if they continue long enough. If one near the equator is observed, the rota
tion would take about twenty-five days; | if one about half-way between the equator and either pole is watched, twenty-seven and a half days. If the "proper motion" of the spots, that is, their motion relative to the sun's surface, is taken into consideration, the sun may be said to rotate on its axis in between twenty-five and twenty-six days.
The sun's axis is not vertical, but inclined toward the point occupied by the earth in September. We learn this from the fact that if spots are watched in June they move across in a straight line; in September in a curve, in December in a straight line, in March in a curve again, but the curve takes the opposite direction. The axis of the sun, therefore, is inclined to the ecliptic, like the earth's. This inclination of the earth's axis to the ecliptic is twenty-three and a half degrees.
In addition to the rotatory motion, the sun is partaking in a mighty revolution, or drift, of the whole universe. "To the unaccustomed eye, the stars seem to pre serve the same relative position in the celestial sphere generation after generation. If Job, Hipparchus or Ptolemy should again look upon the heavens, he would to all appearance see Aldebaran, Orion, and the Pleiades exactly as he saw them thousands of years ago, without a single star being moved from its place. But the refined methods of modern astronomy, in which the telescope is brought to measure spaces absolutely invisible to the eye, have shown that this seeming unchangeability is not real, and that the stars are actually in motion, only the rate of change is so slow that the eye would not, in most cases, notice it for thousands of years.'
The sun's motion relatively to the other stars is four miles per second, and at this rate it carries along with it its planets and their satellites and the attendant meteors and comets of its system. This is by no means a high speed. Arcturus is traveling at the rate of at least 54 miles a second, more than 3,000 times as fast as an express train. By means of the spectroscope the astronomer is investigating this motion. Some stars are approaching, some receding in the line of sight. Sooner or later a grand discovery will tell us more, but at present it seems that as we are approaching the constellation Hercules. The centre of the revolu
tion is a point not more than 90 degrees from it.
It is a mighty conception-the moon revolves round the earth, the earth revolves round the sun, the sun revolves round some other centre with all the systems of the universe. If so, one star will require 185,000 years for its revolution, another 340,000 years, others again many millions of years to complete the circuit. Shelley's words are true: Innumerable systems rolled,
And countless spheres diffused
It was a sight of wonder.
BY J. S. KEIFFER, D. d.
THE world must depend chiefly upon broad-gauge men for the work that
needs to be done for mankind. Such men will always be in demand; there can hardly be too many of them; indeed, that is what all men ought to be or to be tending to become. tending to become. A broad-gauge man is what the name implies; he is more largely built; he rests on a broader foundation; he runs on a wider track; he is capable of carrying more, and of rendering more service in general. This sort of man is of an ample intelligence; takes large views; has an instinct for principles; looks at both sides of a question; is capa ble of considering and judging, of giving counsel and making plans, of directing and controlling. He must be, in some sense, a trained and educated man; untrained nature is almost of necessity narrow. "For expert men," says Bacon,
can execute, and perhaps judge of particulars one by one; but the general counsels and the plots and marshaling of of affairs come best from those that are learned."
Not that broad-gauge men are bred only, or bred always, by institutions of learning. A young man may pass through college and likewise through a theological seminary, or a school of law or of medicine, and yet remain a narrowgauge man in spite of it all. On the other hand, a man may have known little of schools and schooling, in the usual sense of these terms; may have learned the most that he learned from books in a log cabin and by the light of a pine knot; and
yet in spite of all these disadvantages may prove in the long run a splendid broadgauge man. There are different kinds of schools. Nothing, it is true, can ever wholly take the place of the liberal education which it is the object of established institutions of learning to furnish; but some men may find an excellent substitute for it, and may grow into largeness of intelligence and influence and power in the great school of human life and human affairs by contact with people on a large scale, by the wide and earnest study of men and things rather than of books. The ability to see into the nature and relations of things-this is one of the chief characteristics of the liberally educated and broad-minded man; it matters comparatively little in what sort of school he may have acquired this ability. The point is, that he must have been to school somewhere; he must somehow have received a broad and liberal training in order to be a broad-gauge man.
Still, making allowance for all exceptions, it is evident that our chief dependence for a sufficient supply of such men must be upon our educational institutions. This is what such institutions are for. It is the object of education to deliver from pettiness and narrowness, from incompetence and inability. It is an emancipating, enlarging, enlightening, enabling force. It belongs to the very idea of a school, college or university, to broaden and liberalize the mind, to furnish in whatever measure may be possible what is very properly called a liberal education.
It may be questioned whether institutions of learning may not themselves sometimes tend to turn out narrow-gauge rather than broad-gauge men. Very recently two liberally-educated gentlemen, engaged in educational work, and having the most enlightened views as to the object of education, complained to the writer of the difficulties they encountered because of the prevalence of false views in regard to this matter. "Parents say," so they reported, we must find out what this boy is going to be, and educate him for that." The result is that boys fourteen or fifteen years of age are taken away from school and placed at the "business college," to learn type writing, book-keeping, telegraphy or stenography. The principal of a business college, in like manner, recently stated to the writer that young persons came to him for such
instruction in these branches as might fit them for a "position," whose schooling had been so scant that they were not even able to read or spell correctly. So far as this tendency is due to the pressure of necessity and the dire struggle for a livelihood, so far as it is a part of the general situation which drives children into the factories, robbing them of the schooling to which they have a right, so far it is entitled to sympathy and a measure of respect. But so far as it is not due to stern necessity, but is the result and expression of the views of education held by well-todo parents, it deserves only condemnation. This is an evil thing, to deprive education of its enlarging, expanding and liberalizing power; to make the schools themselves, as this tendency threatens to make them, the means of turning out narrow-gauge men.
There are some things which may well be postponed, which the very idea of education demands shall be postponed, for a time; among these is the question, what particular vocation the boy who is being educated shall follow. The proper time will come for determining what his lifework shall be, and for making what special preparation for it may be necessary. First educate the boy, taking time to do it well. Put the instrument he is going to use in good condition; whatever he may do with it afterwards will be the better done. Lay a good foundation; whatever building is erected therein will be the better for it. Make the road-bed broad and the track sufficiently wide; it will be able to carry the more; and there is much to carry-you are in no danger of getting too much carrying power.
The education of a boy is like the whetting of a scythe. The workman whets his scythe that it may be capable of cutting. of cutting. He is not whetting it specially and exclusively for wheat, or grass, or oats, or rye; he is simply putting it in good condition generally, that he may afterwards cut with it whatever it may be necessary to cut. Take time to whet the scythe. Let the boy's powers be developed, trained and disciplined; whatever calling his natural bent or the force of circumstances may in the future lead him to choose, his training will tell in the doing of his work.
The education of a boy is like the tilling of a field. The first thing necessary is, that the field should be in thoroughly good condition; not specially that it
should be in good condition for wheat or corn, but, first of all, that it should be in good condition generally for the production of any crops whatever. When the spring was late, and the weather cold, and many farmers had planted their corn prematurely, the corn perishing in the ground, we heard an experienced farmer say: "I do not count much on early planting; a great deal more depends on having your ground in first-rate condition. I harrow and re-harrow my fields; every harrowing tells upon my crops. So I keep harrowing, and have the ground perfectly mellow, and when the warm weather comes I plant my corn, and it grows right along.
The education of a boy is like the drilling of an army. It is simply preparation; not preparation for any particular battle, but for any and all battles which the army may possibly have to fight. The incessant drilling and the various manoeuvres of the German army are the best possible preparation for any particular campaign in the future. Let the powers of the intellectual nature (and of the moral nature no less, but even more) be drilled like an army, and when the proper time comes let them be led forth to perform their appointed service.
It is hardly possible in these days to protest too strongly against the widely prevalent preference for those educational methods which threaten to deluge the land with men of narrow-gauge, or to insist too earnestly on that long-continued and patient process of general training which has always belonged to the idea of a liberal education, and which in times past has given to the country so many broad-gauge men.
Reformed Church Messenger.
OUR FIRST IDEAS.*
JEAN PAUL says of the child, that it learns more in the first three years of its life than an adult in his three years at the University; that a circumnavigator of the globe is indebted for more notions to his nurse than to all the peoples of the world with whom he may have come into contact. It is, in fact, astounding what a relatively immense stock of ideas a human being gains in the first years of life. He becomes acquainted with the thousand
* From Lange's Apperception, as translated by the Herbartian Club.
things of home, street, garden, field, wood, the wonders of the heavens, the manifold phenomena of nature, the localities and the people of the neighborhood, calling most of them by name. He learns not only to use a great part of the vocabulary of his mother-tongue, and its most important forms of word and sentence, but also to think intelligently in the vernacular.
These numerous ideas are, at the same time, among the most important that a human being ever acquires. They are the first and chief harvest of intellectual activity; the main trunk of the material of thought with which the whole after-life of the soul is concerned. As they are the result of the intercourse of the human being with surrounding nature and with the people of the neighborhood, so they serve in turn to facilitate and advance this intercourse. They are certain also of very frequent use, because of their simplicity and directness. They form, as it were, the capital in iron, the most indispensable minimum of stock in thought, without which a human being could not get along in the most limited surroundings, in the most restricted circle of experience, much less take part in the material and intellectual interests or advancement of his people. They are further pre-requisite to all higher intellectual life, the foundation on which all true culture rests.
LOOKING UPON THE UNSEEN.
UR sight is so priceless a blessing that we are very seldom conscious of its limitations. We trust it implicitly, and, while we cling to it as one of our dearest possessions, we are somewhat inclined to ignore or depreciate by comparison the great realm of the unseen. "I will believe it when I see it," is a common expression of this state of mind, implying that what is not seen is deserving of slight credence. Yet the truth is that our physical sight is limited within such narrow bounds that if our minds went no further we should be blind and ignorant indeed.
Even of the material world, our eyes give us but a trifling glimpse. How little do we see of the city, even from the top of the tallest building, or of the broad expanse of the country, even from the summit of the highest mountain! What proportion of the vast universe can the keen