II
13. Isaac possessed a wonderful power of gaining knowledge by the simplest means. For instance, what method do you suppose he took to find out the strength of the wind? You will never guess how the boy could compel that unseen, inconstant, and ungovernable wonder, the wind, to tell him the measure of its strength.
14. Yet nothing can be more simple. He jumped against the wind; and by the length of his jump he could calculate the force of a gentle breeze or a tempest. Thus, even in his boyish sports he was continually searching out the secrets of philosophy.
15. Not far from his grandmother's house there was a windmill which worked on a new plan. Isaac was in the habit of going thither frequently, and would spend whole hours in examining its various parts. While the mill was at rest he pried into its machinery.
The windmill
16. When its broad sails were set in motion by the wind, he watched the process by which the millstones were made to turn and crush the grain that was put into the hopper. After gaining a thorough knowledge of its construction, he was observed to be unusually busy with his tools.
17. It was not long before his grandmother and all the neighborhood knew what Isaac had been about. He had constructed a model of the windmill. Though not so large, I suppose, as one of the box traps which boys set to catch squirrels, yet every part of the mill and its machinery was complete.
18. Its little sails were neatly made of linen, and whirled round very swiftly when the mill was placed in a draught of air. Even a puff of wind from Isaac's mouth or from a pair of bellows was sufficient to set the sails in motion. And, what was most curious, if a handful of grains of wheat was put into the little hopper, they would soon be converted into snow-white flour.
19. Isaac's playmates were enchanted with his new windmill. They thought that nothing so pretty and so wonderful had ever been seen in the whole world.
"But, Isaac," said one of them, "you have forgotten one thing that belongs to a mill."
20. "What is that?" asked Isaac; for he supposed that, from the roof of the mill to its foundation, he had forgotten nothing.
"Why, where is the miller?" said his friend.
"That is true; I must look out for one," said Isaac; and he set himself to consider how the deficiency should be supplied.
21. He might easily have made a little figure like a man; but then it would not have been able to move about and perform the duties of a miller. It so happened, however, that a mouse had just been caught in the trap; and, as no other miller could be found, Mr. Mouse was appointed to that important office.
22. The new miller made a very respectable appearance in his dark gray coat. To be sure, he had not a very good character for honesty, and was suspected of sometimes stealing a portion of the grain which was given him to grind. But perhaps some two-legged millers are quite as dishonest as this small quadruped.
23. As Isaac grew older, it was found that he had far more important matters in his mind than the manufacture of toys like the little windmill. All day long, if left to himself, he was either absorbed in thought or engaged in some book of mathematics or natural philosophy.
24. At night, I think it probable, he looked up with reverential curiosity to the stars and wondered whether they were worlds like our own, and how great was their distance from the earth, and what was the power that kept them in their courses. Perhaps, even so early in life, Isaac Newton felt that he should be able some day to answer all these questions.
25. When Isaac was fourteen years old, his mother's second husband being now dead, she wished her son to leave school and assist her in managing the farm at Woolsthorpe. For a year or two, therefore, he tried to turn his attention to farming. But his mind was so bent on becoming a scholar that his mother sent him back to school, and afterwards to the University of Cambridge.