“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!” “I don’t grasp it any better,” said Jules. “Nor I, it is so enormous,” assented his uncle. “Yes, enormous, Uncle.” “So that the mind gets lost in it,” said Claire. “That is what I wanted to make you acknowledge,” concluded Uncle Paul. ------------------------------------------------------------------------ CHAPTER LIII THE ATMOSPHERE