Principes de la Montre de M. Harrison, Avec Les Planches Relatives À la Même Montre

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W. Richardson, 1767 - 66 pages
 

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Page 20 - Balance-fpring has; and it muft be allowed, the lefs the Wheels have to do with the Balance, the better.. The Wheels in a common Watch having this great Dominion over the Balance, they can, when the Watch is wound up, and the Balance at...
Page 21 - Angle in Proportion to the Vibration that it is to fetch, than the Force of the Wheels of a common Regulator can move the Pendulum from the Perpendicular, when it is at reft. My Time-keeper's Balance is more than three times the Weight of a large fized common...
Page 21 - ... diameter ; and a common Watch-balance goes through about six Inches of Space in a Second, but mine goes through about twenty-four Inches in that Time : So that had my Time-keeper only these Advantages over a common Watch, a good Performance might be expected from it. But my Timekeeper is not affected by the different Degrees of Heat and Cold, nor Agitation of the Ship ; and the Force from the Wheels is applied to the Balance in such a Manner, together with the Shape of the Balance-spring, and...
Page xii - thermometer kirb,' he himself says,' is composed of two thin plates of brass and steel, riveted together in several places, which, by the greater expansion of brass than steel by heat and contraction by cold, becomes convex on the brass side in hot weather and convex on the steel side in cold weather; whence, one end being fixed, the other end obtains a motion corresponding with the changes of heat and cold, and the two pins at the end, between which the balance spring passes, and which it...
Page 19 - TIME-KEEPER. IN this Time-keeper there is the greateft Care taken to avoid Friction as much as can be, by the Wheels • moving on fmall Pivots, and in Ruby-holes, and high Numbers in the Wheels and Pinions. The Part which meafu res Time goes but the eighth ! Part of a Minute without winding up; fo that Part is very fimple, as this Winding-up is performed at the...
Page 21 - ... Time-keeper's Balance is more than three times the Weight of a large sized common Watch-balance, and three times its diameter ; and a common Watch-balance goes through about six Inches of Space in a Second, but mine goes through about twenty-four Inches in that Time : So that had my Time-keeper only these Advantages over a common Watch, a good Performance might be expected from it. But my Timekeeper is not affected by the different Degrees of Heat and Cold, nor Agitation of the Ship ; and the...
Page 19 - Timple, as this w'|nding-up is performed at the» wheel next to the balance-wheel ; by which means there is always an equal force ac'ting at that wheel, and all the reft of the work has no more to do in mealuring time, than the perfon that winds them up once a day.
Page 20 - Spring fupplies its Place. In common Watches in general the Wheels have about One-third the Dominion over the Balance that the...
Page 21 - ... Advantages over a common Watch, a good Performance might be expected from it. But my Timekeeper is not affected by the different Degrees of Heat and Cold, nor Agitation of the Ship ; and the Force from the Wheels is applied to the Balance in such a Manner, together with the Shape of the Balance-spring, and (if I may be allowed the Term) an artificial Cycloid, which acts at this Spring ; so that from these Contrivances, let the Balance vibrate more or less, all its Vibrations are performed in...
Page 20 - Balance is at reft, and the Spring is wound up, the Force of the Wheels can no more fet it a-going, than the Force of the Wheels of a common Regulator can, when the Weight is wound up, fet the...

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