Chapter 32: 315-326
Contents
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in the design of the Remontoire
In mechanical horology, a remontoire, (from the French remonter, meaning 'to wind') is a small secondary source of power, a weight or spring, which runs the timekeeping mechanism and is itself periodically rewound by the timepiece's main power source, such as a mainspring. In precision clocks and watches it is often used to place the source of power closer to the escapement thereby increasing the accuracy by evening out variations in drive force caused by unevenness of the friction in the geartrain. In spring-driven precision clocks a gravity remontoire is often used to replace the uneven force delivered by the mainspring running down by the more constant force of gravity acting on a weight. In turret clocks it serves to separate the large forces needed to drive the hands from the modest forces needed to drive the escapement which keeps the pendulum swinging. A remontoir should not be confused with a maintaining power spring, which is used only to keep the timepiece going while it is being wound. From WIKI
Prandium gratis non est
There is no such thing as a free lunch
"Power may be borrow'd, as needed, against repayment dates deferrable indefinitely."
The watch runs on some major credit
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Compound Interest
Compound interest was once regarded as the worst kind of usury, and was severely condemned by Roman law, as well as the common laws of many other countries. Richard Witt's book Arithmeticall Questions, published in 1613, was a landmark in the history of compound interest. It was wholly devoted to the subject (previously called anatocism), whereas previous writers had usually treated compound interest briefly in just one chapter in a mathematical textbook. Witt's book gave tables based on 10% (the then maximum rate of interest allowable on loans) and on other rates for different purposes, such as the valuation of property leases. Witt was a London mathematical practitioner and his book is notable for its clarity of expression, depth of insight and accuracy of calculation, with 124 worked examples. From WIKI
