Treatise on Clock and Watch Making: Theoretical and PracticalCarey and Lea, 1832 - 476 páginas |
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Treatise on Clock and Watch Making: Theoretical and Practical Thomas Reid Visualização completa - 1826 |
Treatise on Clock and Watch Making: Theoretical and Practical Thomas Reid Visualização completa - 1832 |
Treatise on Clock and Watch Making: Theoretical and Practical - Primary ... Thomas Reid Prévia não disponível - 2014 |
Termos e frases comuns
arbor astronomical clock axis balance spring balance wheel barrel bell Berthoud brass carries centre circle circumference cock compensation contrate wheel contrived cylinder degree detent dial distance ditto divided divisors edge endless screw equal equation Ferdinand Berthoud fixed force fourth wheel fraction frame fusee give given gridiron pendulum half hammer hole inch in diameter isochronism lever locking lower end means minute wheel month wheel motion multiplied nearly notch number of teeth number of turns number of vibrations pallet pendulum ball pendulum rod pendulum spring piece of brass pitching pivots plate pulley pyrometer quarter quotient rack ratchet ratio regulating remontoir revolution roller round scapement sector seen side socket space square steel rods striking stud supposed swing wheel thick third wheel time-keepers tion tooth tube turret clocks verge watch weight wheel teeth wheels and pinions whole number zinc
Passagens mais conhecidas
Página 229 - ... ways would have brought the vibrations of the balance within a shorter compass. Now, what device must be fallen on, in order to lessen the arc of vibration, so as the balance shall not go so far as to make a second unlocking, keeping still the same train of wheels, and the same force of main-spring ? There is only one way to do this, and that is by increasing the diameter of the balance, which will then require a stronger pendulum spring, and this will of course give a little more opposition...
Página 7 - ... having a spiral groove cut on it : on the bottom of this cone, or fusee, the first or great wheel is put. The arbor, on which the spring barrel turns, is so fixed in the frame, that it cannot turn when the fusee is winding up : the inner end of the spring hooks on to the barrel arbor, and the outer end hooks to the inside of the barrel.
Página 4 - VI, to be of sach consequence, that the king gave the keeping of it, with the appurtenances, to William Warby, dean of St. Stephen's, together with the pay of sixpence per diem, to be received at the Exchequer.
Página 270 - ... on the top of the mucilage. When time has thus completed the operation, the pure oil must be poured off into very small phials, and kept in a cool place, well corked, to preserve it from the air* AERIAL NAVIGATION.
Página 8 - The wheels, in any sort of movement, when at liberty, or free to turn, and when impelled by a force, whether it is that of a weight or of a spring, would soon allow this force to terminate ; for, as the action of the force is constant from its first commencement, the wheels would be greatly accelerated in their course, and it would be an improper machine to register time or its parts. The necessity of checking this acceleration, and making the wheels move with a uniform motion, gave rise to the invention...
Página 467 - Description of two methods, by which the Irregularities in the motion of a Clock, arising from the influence of Heat and Cold upon the rod of the pendulum, may be prevented, etc.
Página 314 - Before the introduction of railways, people used to set their clocks by the sun. But owing to the obliquity of the ecliptic and the eccentricity of the earth's orbit around the sun, the intervals between successive passages of the sun are not exactly equal. The consequence is that, if a clock keeps exact time, the sun will sometimes pass the meridian before and sometimes after twelve by the clock. When this was understood, a distinction was made between apparent...
Página 285 - Thus, supposing the given number of equal divisions of a circle on the dividing plate to be 69 ; subtract 9, and there will remain 60. Every circle is supposed to contain 360 degrees : therefore say, As the given number of parts in the circle, which is 69, is to 360 degrees, so...
Página 164 - RULE.* To three times the square of the radius of its base add the square of its height ; and this sum multiplied by the height, and the product again by .5236, will give the solidity.
Página 407 - Hanway ; namely twenty-one feet, four inches and a half. In the stoutest part, that in which it should have received the blow of the hammer, its thickness equalled twentythree inches. We were able to ascertain this, by placing our hands, under water, where the fracture has taken place : this is above seven feet high from the lip of the bell.