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but couldn't remember where he had put the formula. Pressed by Halley, Newton agreed to redo the calculations and produce a paper. He did as promised, but then did much more. He retired for two years of intensive reflection and scribbling, and at length produced his masterwork: the Philosophiae Naturalis Principia Mathematica or Mathematical Principles of Natural Philosophy, better known as the Principia. Once in a great while, a few times in history, a human mind produces an observation so acute and unexpected that people can't quite decide which is the more amazing—the fact or the thinking of it. Principia was one of those moments. It made Newton instantly famous. For the rest of his life he would be draped with plaudits and honors, becoming, among much else, the first person in Britain knighted for scientific achievement. Even the great German mathematician Gottfried von Leibniz, with whom Newton had a long, bitter fight over priority for the invention of the calculus, thought his contributions to mathematics equal to all the accumulated work that had preceded him. “Nearer the gods no mortal may approach,” wrote Halley in a sentiment that was endlessly echoed by his contemporaries and by many others since. Although the Principia has been called “one of the most inaccessible books ever written” (Newton intentionally made it difficult so that he wouldn't be pestered by mathematical “smatterers,” as he called them), it was a beacon to those who could follow it. It not only explained mathematically the orbits of heavenly bodies, but also identified the attractive force that got them moving in the first place—gravity. Suddenly every motion in the universe made sense. At Principia's heart were Newton's three laws of motion (which state, very baldly, that a thing moves in the direction in which it is pushed; that it will keep moving in a straight line until some other force acts to slow or deflect it; and that every action has an opposite and equal reaction) and his universal law of gravitation. This states that every object in the universe exerts a tug on every other. It may not seem like it, but as you sit here now you are pulling everything around you—walls, ceiling, lamp, pet cat—toward you with your own little (indeed, very little) gravitational field. And these things are also pulling on you. It was Newton who realized that the pull of any two objects is, to quote Feynman again, “proportional to the mass of each and varies inversely as the square of the distance between them.” Put another way, if you double the distance between two objects, the attraction between them becomes four times weaker. This can be expressed with the formula
A Short History of Nearly Everything
Bill Bryson
But while the southern price index rose to 686 (February 1861 = 100) by the end of 1862, the northern index then stood only at 114. For the war as a whole the Union experienced inflation of only 80 percent (contrasted with 9,000 percent for the Confederacy), which compares favorably to the 84 percent of World War I (1917–20) and 70 percent in World War II (1941–49, including the postwar years after the lifting of wartime price controls). While the greenbacks’ lack of a specie backing created a speculator’s market in gold, the “gold premium” did not rise drastically except in periods of Union military reverses. During the four months after passage of the Legal Tender Act, the gold premium rose only to 106 (that is, 100 gold dollars would buy 106 greenback dollars).
The Illustrated Battle Cry of Freedom
James M. McPherson
It’s worth noting that the lower lungs are loaded with parasympathetic nerve receptors that, when stimulated through belly breathing, help spread a sense of calm throughout the body and mind. When you chest breathe, those lovely lower-lung receptors go untouched. Chest breathing does, on the other hand, do a stellar job of triggering the sympathetic nerve receptors located in the upper part of the lungs. As a result, your fight-or-flight reaction gets switched on when it doesn’t need to be . . . sometimes 24/7. You’ll feel stressed, anxious, tired, and on edge while increasing your risk of a host of chronic diseases, including heart disease, depression, cancer, and more.
Heart Breath Mind
Leah Lagos
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