Book I. Of the apparent motions of the celestial bodies. Book II. Of the real motions of the celestial bodies. Book III. Of the laws of motionRichard Phillips, Bridge Street, Blackfriars. ... W. Flint, printer, Old Bailey., 1809 - 380 pages |
Common terms and phrases
altitude angle angular apparent diameter appear astronomical atmosphere augments celestial centre of gravity centrifugal force CHAP circle circumference comet contrary curve degree density described determined diminishes direction disk displaced fluid diurnal motion duration eclipses equal equator equilibrium extremely fixed stars fluid greater axis height horizon inequality instant interval Jupiter latitude laws length light lunar manner Mars mass material points mean distance measure Mercury metre Moon motion of rotation move nature nearly nodes observed orbit oscillations parallax parallel pendulum perigee perihelion perpendicular phenomena planet pole position produce proper motion proportional quadratures quantity radius vector rays real motion relative retrograde retrograde motion revolution right ascension round the Earth round the Sun Saturn sidereal sine solar solicited solid of revolution solstice square straight line suppose surface system of bodies sysygies tangent temperature terrestrial meridian tion unity Uranus variations velocity Venus vernal equinox vertical vis viva
Popular passages
Page 113 - ... there seems to be a disposition to assent to it from the simplicity of the statement. 3. The spherical is one of the most simple of all re-entering figures, since it depends only on a single element, the size of its radius. The natural inclination of the human mind, to attribute that form to bodies which it comprehends with the greatest facility, disposed it to give the earth a spherical form. But the simplicity of nature should not always be measured by our conceptions. It was no sooner discovered...
Page 269 - ... that the mean longitude of the first satellite, minus three times that of the second, plus twice that of the third, is always equal to two right angles.
Page 341 - ... is equal to the weight of a prism of the fluid whose base is the same as the bottom of the vessel, and whose altitude is, the distance between the bottom and the upper surface of the fluid...
Page 65 - Mercury's oscillation from west to east, or from east to west, is really accomplished in just half the time of its revolution, which is about 44 days; but as the Earth, in the meantime, follows the Sun in the same direction, the apparent elongations will be prolonged to between 55 and 55 days.
Page 214 - All these bodies will appear to move from west to east; already this identity in the direction indicates a motion of the Earth, but that which demonstrates it evidently is the law which exists between the times of the revolutions of the planets, and their distance from the Sun. They revolve round it slower as their distances are greater, and in such a manner that the squares of the periodic time are in proportion to the cubes of their mean distances.
Page 93 - The appearance of comets followed by these trains of light, has for a long time terrified mankind, always agitated by extraordinary events, of which the causes are unknown. The light of science has...
Page 365 - ... the centre, and by its distance from the same centre, is always independent of any mutual action which the bodies...
Page v - Of all the natural sciences, Astronomy is that which presents the longest series of discoveries; There is an immense distance from, the first view of the heavens, to that general view by which, at the present day, we comprehend the past and future state of the system of the world. To arrive at this, it was necessary to observe the heavenly bodies during a long succession of ages,— to recognize from their appearances the real motion of the Earth, — to develop...
Page 204 - But since the heavenly bodies present the same appearances to us, whether the firmament carries them round theearth, considered as immoveable, or whether the earth itself revolves in a contrary direction, it seems much more natural to admit this latter motion, and to regard that of the heavens as only apparent. The earth is a globe, not 8000 miles in diameter; but the diameter of the Sun is nearly 100 times larger.
Page 148 - ... derived in a manner the least arbitrary from a fundamental measure, indicated by nature itself, would be one of the greatest services which science and government can render to the human race. A people who should adopt such a system of measures, would unite to the advantage of gathering the first fruits of it, that of seeing their example followed by other nations, of which it would thus become the benefactor. For the slow but irresistible empire of reason, at length overcomes all the national...