E ARLY in the morning Uncle Paul and his nephew climbed the neighboring hill to see the sunrise. It was still quite dark.
Sheltered by a clump of juniper-trees, Uncle Paul and the three children await the grand spectacle they have come to the top of the hill to see. In the east the sky is getting lighter, the stars turn pale and go out one by one. Flakes of rosy cloud swim in a brilliant streak of light whence gradually there rises a soft illumination. It reaches the zenith, and the blue of day reappears with all its delicate transparency. This cool morning light, this half-daylight that precedes the rising of the sun, is the aurora or morning twilight. In the meantime a lark, the joy of the fields, takes wing to the highest clouds, like a rocket, and is the first to salute the awakening day. It mounts and mounts, always singing, as if to get in front of the sun; and with its enthusiastic songs it celebrates in the high heavens the glory of the day-bringer. Listen: there is a breath of wind in the foliage, which stirs and rustles; the little birds are waking up and chirping; the ox, already led to work in the fields, stops as if thinking, raises its large eyes full of gentleness, and lows; everything becomes animated, and, in its own language, renders thanks to the Master of all things, who with His powerful hand brings us back the sun.
And here it is: a bright thread of light bursts forth, and the tops of the mountains are suddenly illumined. It is the edge of the sun beginning to rise. The earth trembles before the radiant apparition. The shining disc keeps rising: there it is almost whole, now completely so, like a grindstone of red-hot iron. The mist of the morning moderates its glare and allows one to look it in the face; but soon no one could endure its dazzling splendor. In the meantime its rays inundate the plain; a gentle heat succeeds the keen freshness of the night; the mists rise from the depths of the valleys and are dissipated; the dew, gathered on the leaves, becomes warm and evaporates; on all sides there is a resumption of life, of the animation suspended during the night. And all day, pursuing its course from east to west, the sun moves on, flooding the earth with light and heat, ripening the yellow harvest, giving perfume to the flowers, taste to fruit, life to every creature.
Then Uncle Paul, in the shade of the juniper-trees, began his talk.
"What is the sun? Is it large, is it very far away? That, my children, is what I should now like to teach you.
"To measure the distance from one point to another, you know of only one means: that of laying off, as many times as it will go, the unit of length, the meter, from one end to the other of the distance to be measured. But science has methods adapted to the measuring of distances that one cannot travel in person; it tells us what must be done to find the height of a tower or mountain, without going to the top, without even approaching the base. They are methods of the same kind as are employed to calculate the distance that separates us from the sun. The result of the astronomer's calculations is that we are distant from the sun 38 millions of leagues of 4000 meters each. This distance is equivalent to 3800 times the circumference of the earth. I told you that, to make the tour of the terrestrial globe, a man, a good walker, capable of walking ten leagues a day, would take about three years. He would need, then, nearly twelve thousand years to go from the earth to the sun, supposing that the journey were possible. The longest human life is incomparably too short for a journey of this length ever to be accomplished by one person; and a hundred generations of a hundred years each, succeeding one another on the journey and uniting their efforts, would not even be enough."
"And a locomotive," asked Jules, "how long would it take to get over that distance?"
"Do you remember how fast it goes?"
"I saw it myself the day we took the trip with you. If one looks out, the road seems to fly back so fast it frightens you and makes you dizzy."
"The locomotive that drew us went at the rate of about ten leagues an hour. Let us suppose a locomotive that never stops and that goes still faster, or fifteen leagues an hour. Rushing at that speed, the engine would go from one end of France to the other in less than a day; and yet, to cover the distance from the earth to the sun, it would take more than three centuries. For such a journey, the fastest engine ever made by the hand of man is hardly more than a sluggish snail ambitious to make the tour of the world."
"And I who thought, not long ago," said Emile, "that by climbing to the roof and with the aid of a long reed I could touch the sun!"
"To one who trusts to appearances the sun is only a dazzling disc, at the most as large as a grindstone."
"That is what I said yesterday," observed Jules. "But, as it is so far away, it might well be as large as a millstone."
"In the first place, the sun is not flat like a grindstone; it has, like the earth, the shape of a ball. Furthermore, it is much larger than a grindstone, or even than a millstone.
"Objects seem to us small in proportion to their distance from us, until finally they become invisible. A high mountain seen from afar seems only a moderate-sized hill; the cross that surmounts a steeple, seen from below, looks very small despite its very large dimensions. It is the same with the sun: it looks so small only because it is very far off; and as the distance is prodigious, its size must be excessive; if not, instead of looking to us like a dazzling grindstone, it would cease to be visible to us.
"You found the terrestrial globe enormous; and, despite my comparisons, your imagination, I am sure, has not been able to picture things properly. How will it be with the sun, which is one million four hundred thousand times as large as the earth! If we suppose the sun hollow like a spherical box, to fill it would take one million four hundred thousand balls the size of the earth.
"Let us try another comparison. To fill the measure of capacity called the liter, it takes about 10,000 grains of wheat. It would take, then, 100,000 to fill 10 liters or one decaliter, and 1,400,000 to fill 14 decaliters. Well, suppose in one pile 14 decaliters of wheat, and beside it one solitary grain of wheat. For the respective sizes, this isolated grain represents the earth; the pile of 14 decaliters represents the sun."
"How wrong we were!" Claire exclaimed. "This little shining disc, to which, for fear of exaggeration, we should have hesitated to assign the dimensions of a millwheel, is a globe so big that in comparison with its gigantic size the earth is as nothing."
"Oh, God in heaven!" cried Jules.
"Yes, my friend, you may well say, 'God in heaven,' for the mind is bewildered at the thought of this inconceivable mass. Say: God in heaven! how great You are, You who out of nothing have created the sun and the earth, and hold them both in the shadow of Your hand!
"I have not finished, my dear children. One day, in speaking to you of lightning and thunder, I told you that light moves with excessive rapidity. In fact, to come to us from the sun, to cover the distance that a locomotive at its highest speed would take three hundred years to cover, a ray of light needs only the half of a quarter of an hour, or about eight minutes. Now listen to this. Astronomy teaches us that each star, small as it may appear from here, is itself a sun comparable in size to ours; it tells us that these suns, of which we with the naked eye can perceive only a very small part, are so numerous that it is impossible to count them; it tells us that their distance is so great that, to come to us from the nearest star, light, which travels so fast, as I have just told you, takes nearly four years; to reach us from others that are by no means the most distant it takes whole centuries. After that, if you can, estimate the distance that separates us from those far-off suns; think also of their number and size. But no, do not try: the intellect is overwhelmed by these immensities in which is revealed all the majesty of God's handiwork. Do not try, it would be in vain; but let arise from your heart the burst of admiration that you cannot suppress, and bless God, whose infinite power has scattered suns through the boundless regions of celestial space."