“The power of a locomotive is no doubt considerable; however, if it is able to draw with great speed a long train of cars, all heavily loaded, this is due, above all, to the preparation of the road on which it runs. Strong bars of iron, called rails, are fixed solidly on the road, all along its length, in two parallel lines, on which all the wheels of the train roll without ever running off. A light flange with which the wheels are furnished keeps the train from slipping off the rails.

“The iron road not having the inconveniences of other roads, that is to say the ruts, pebbles, and inequalities that impede the progress of carriages and cause the waste of much energy, the whole traction of the locomotive is utilized, and the results obtained are wonderful. A passenger engine draws at a rate of twelve leagues an hour a train weighing as much as 150,000 kilograms. A freight engine pulls at about seven leagues an hour a total weight of 650,000 kilograms. More than 1300 horses would be necessary to replace the first locomotive, and more than 2000 to replace the second, if they were employed to transport similar loads with the same velocity and to the same distances by the aid of cars running on rails. What an army of horses it would require with wagons running on ordinary roads having all the inequalities that cause such a great loss of energy!

“And now, my little friends, think of the thousands of locomotives running daily in all parts of the world, annihilating distances, as it were, and bringing the most distant nations together; think what a vast number of machines of all kinds, moved by steam, are ceaselessly working for man; think how the engine that makes a warship move, sometimes represents in itself the united strength of 42,000 horses; think of all these things, and see what inconceivable development of power man’s genius has given to him with a few shovelfuls of coal burning under a pot of water!”

“Who first thought of the use of steam?” asked Jules. “I should like to remember his name.”

“The use of steam as a mechanical power was proposed nearly two hundred years ago by one of the glories of France, the unfortunate Denis Papin, who, after giving the first suggestion of the steam-engine, source of incalculable riches, languished in a foreign land, poverty-stricken and forlorn. To realize his fruitful idea, which was to increase man’s motive power a hundredfold, he could hardly find a paltry half-crown.”

CHAPTER L
EMILE’S OBSERVATION

EMILE’S turn came to tell what he had seen.

“When you made me a sign to be silent,” said he, “it seemed to me as if the trees were walking. Those along the railroad were going very fast; farther away, the big poplars, ranged in long rows, were going with their heads waving as if saying good-by to us. Fields turned around, houses fled. But on looking closer I soon saw that we were moving and all the rest was motionless. How strange! You see something running that is really not moving at all.”

“When we are comfortably seated in the railway car,” his uncle replied, “without any effort on our part to go forward, how can we judge of our motion except by the position we occupy in relation to the objects that surround us? We are aware of the way we are going by the continual changing of the objects in sight, and not by any feeling of fatigue, since we do not move our legs. But the objects and people nearest to us and always before our eyes, our traveling companions and the furnishings of the car, remain for us in the same position. The left-hand neighbor is always at the left, the one in front is always in front. This apparent immobility of everything in the car makes us lose consciousness of our own movement; then we think ourselves immobile and fancy we see flying in an opposite direction exterior objects, which are always changing as we look at them. Let the train stop, and immediately trees and houses cease moving, because we no longer have a shifting point of view. A simple carriage drawn by horses, a boat borne along by the current, lend themselves to this same curious illusion. Every time we ourselves are gently moved along, we tend, more or less, to lose consciousness of this movement, and surrounding objects, in reality immobile, seem to us to move in a contrary direction.”