“Only four leagues! All the same I was played out. At the end I could hardly put one foot before the other. It would take me, then, from seven to eight years to go round the world, walking every day as far as my strength would let me.”
“Your calculation is right.”
“The earth then is a very large ball?”
“Yes, my friend, very large. Another example will help you to understand it. Let us represent the terrestrial globe by a ball of greater diameter than a man’s height—by a ball two meters in diameter; then, in correct proportion, represent in relief on its surface some of the principal mountains. The highest mountain in the world is Gaurisankar, a part of the Himalaya chain, in central Asia. Its peaks rise to a height of 8840 meters. Rarely are the clouds high enough to crown its crest, and its base covers the extent of an empire. Alas! what does man become, materially, in face of such a prodigious colossus! Well, let us raise the giant on our large ball representing the earth; do you know what will be needed to represent it? A tiny little grain of sand which would be lost between your fingers, a grain of sand that would stand out in relief only a millimeter and a third! The gigantic mountain that overwhelmed us with its immensity is nothing when compared with the earth. The highest mountain in Europe, Mont Blanc, whose height is 4810 meters, would be represented by a grain of sand half as large as the other.”
“When you told us of the roundness of the earth,” put in Claire, “I thought of the enormous mountains and deep valleys, and asked myself how, with all these great irregularities, the earth could nevertheless be round. I see now that these irregularities are a mere nothing in comparison with the immensity of the terrestrial ball.”
“An orange is round in spite of the wrinkles in its skin. It is the same with the earth: it is round in spite of the irregularities of its surface; it is an enormous ball sprinkled with grains of dust and sand proportioned to its size, and these are mountains.”
“What a big ball!” exclaimed Emile.
“To measure the circumference of the earth is not an easy thing, you may be sure; and yet they have done more than that: they have weighed the immense ball as if it were possible to put it in a scale-pan with kilograms for counterweights. Science, my dear children, has resources demonstrating in all its grandeur the power of the human mind. The immense ball has been weighed. How it was done cannot be explained to you to-day. No scales were used, but it was accomplished by the power of thought with which God has endowed us, to solve, to His glory, the sublime enigma of the universe; by the force of reason, for which the burden of the earth is not too heavy. This burden is expressed by the figure 6 followed by twenty-one zeros, or by 6 sextillions of kilograms.”
“That number means nothing to me; it is too large,” Jules declared.
“That is the trouble with all large numbers. Let us get around the difficulty. Suppose the earth placed on a car and drawn on a surface like that of our roads. For such a load, what should the team be? Let us put in front a million horses; and in front of that row a second million; then a third row, still of a million; a hundredth, finally a thousandth. We shall thus have a team of a thousand millions of horses, more than could be fed in all the pastures of the world. And now start; apply the whip. Nothing would move, my children; the power would be insufficient. To start the colossal mass, it would need the united efforts of a hundred millions of such teams!”