Newton and the Counterfeiter Read Online Free PDF Page A

what he and his contemporaries thought they knew about the most basic concepts of matter and motion just to arrive at a set of definitions that he could turn to account. For example, he was still groping for a way to express the crucial conception of force that would allow him to bring the full force of mathematics to bear. By 1666, he had got this far: "Tis known by y e light of nature ... y t equall forces shall effect an equall change in equall bodys ... for in loosing or ... getting y e same quantity of motion a body suffers the y e same quantity of mutation in its state."
    The core of the idea is there: that a change in the motion of a body is proportional to the amount of force impressed on it. But to turn that conception into the detailed, rich form it would take as Newton's second law of motion would require long, long hours of deep thought. The same would prove to be true for all his efforts over the next twenty years as they evolved into the finished edifice of his great work,
Philosophiœ naturalis principia mathematica
—The Mathematical Principles of Natural Philosophy—better known as the
Principia.
For all his raw intelligence, Newton's ultimate achievement turned on his genius for perseverance. His one close college friend, John Wickens, marveled at his ability to forget all else in the rapt observation of the comet of 1664. Two decades later, Humphrey Newton, Isaac Newton's assistant and copyist (and no relation), saw the same. "When he has sometimes taken a turn or two [outdoors] has made a sudden stand, turn'd himself about and run up y e stairs, like another Archimedes, with an Eureka, fall to write on his Desk standing, without giving himself the Leasure to draw a Chair to sit down in." If something mattered to him, the man pursued it relentlessly.
    Equally crucial to his ultimate success, Newton was never a purely abstract thinker. He gained his central insight into the concept of force from evidence "known by y e light of nature." He tested his ideas about gravity and the motion of the moon with data drawn from his own painstaking experiments and the imperfect observations of others. When it came time to analyze the physics of the tides, the landlocked Newton sought out data from travelers the world over; barely straying from his desk in the room next to Trinity College's Great Gate, he gathered evidence from Plymouth and Chepstow, from the Strait of Magellan, from the South China Sea. He stabbed his own eye, built his own furnaces, constructed his own optical instruments (most famously the first reflecting telescope); he weighed, measured, tested, smelled, worked—hard—with his own hands, to discover the answer to whatever had sparked his curiosity.

    Newton labored through the summer. That September, the Great Fire of London came. It lasted five days, finally exhausting itself on September 7. Almost all of the city within the walls was destroyed, and some beyond, 436 acres in all. More than thirteen thousand houses burned, eighty-seven churches, and old St. Paul's Cathedral. The sixty tons of lead in the cathedral roof melted; a river of molten metal flowed into the Thames. Just six people are known to have died, though it seems almost certain that the true number was much greater.
    But once the fire destroyed the dense and deadly slums that cosseted infection, the plague finally burned itself out. That winter, reports of cases dropped, then vanished, until by spring it became clear that the epidemic was truly done.
    In April 1667, Newton returned to his rooms at Trinity College. He had left two years earlier with the ink barely dry on his bachelor of arts degree. In the interval, he had become the greatest mathematician in the world, and the equal of any natural philosopher then living. No one knew. He had published nothing, communicated his results to no one. So the situation would remain, in essence, for two decades.

3. "I Have Calculated It"
    I SAAC NEWTON CLAMBERED up the