INTRODUCTORY FABLE
Pedro accepted his explanation of the principle slowly.
"There must be some hidden defect in the device," he insisted. "Look around us. Nowhere does Nature employ the device you call the wheel. Observe the mechanism of the human body; observe the horse's frame; observe . . ."
"Observe that horse and man and waggon with its wheels are speeding from us," replied Luis, laughing. " Cannot you yield to accomplished facts? You tire me with your appeals to Nature. Has man ever accomplished anything worth having except by combating Nature? We do violence to her when we chop down a tree! I would go further than this invention of the waggon. Conceive a more powerful motive force than that horse . . ."
"Attach two horses to the waggon."
"I mean a machine," said Luis.
" A mechanical horse with powerful iron legs!" suggested Pedro.
"No; I would have a motor waggon. If I could find an artificial force I would cause it to act on a point in the circumference of each wheel. Then the waggon could carry its own puller!"
"You might as well attempt to lift yourself
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