Library of Useful Knowledge: Natural philosophy, Volumen3Baldwin and Cradock, 1834 |
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Términos y frases comunes
aberration altitude apogee apparent diameter ascer ascertained astronomers axis calculated called centre circle comet consequently corresponding course declination deduced degree determined direction ecliptic effect equal equator equinox excentricity fixed stars given greater greatest heavenly body heavens Hipparchus horizon hour angle inferior planet instance Jupiter Kepler known latitude latter length less longitude lunar mean anomaly measured meridian method moon moon's nearly node nutation obliquity observed orbit parallax parallel passing perigee perpendicular planet pole position precession proportion Ptolemy quantity radius refraction remarkable respect retrograde retrograde motion revolution revolve right angle right ascension rotation round the earth round the sun satellites seen side sidereal sine solar solstice South sphere spherical sun's superior planet supposed supposition Surya Siddhanta synodic period tables tance tangent tion triangle true tude variation varies velocity whole zenith distance
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Página 18 - If two triangles have one angle of the one equal to one angle of the other and the sides about these equal angles proportional, the triangles are similar.
Página 155 - D'Alembert, was the Precession of the equinoxes and the Nutation of the earth's axis, according to the theory of gravitation.
Página 46 - Having given the radius of an arc of any colour in the secondary rainbow, find the ratio of the sine of incidence to the sine of refraction when rays of that colour pass out of air into water.
Página 9 - The lowest and most level parts of the earth, when penetrated to a very great depth, exhibit nothing but horizontal strata composed of various substances, and containing almost all of them innumerable marine productions. Similar strata, with the same kind of productions, compose the hills even to a great height. Sometimes the shells are so numerous as to constitute the entire body of the stratum. They are almost...
Página 28 - Scotland was divided into two provinces — the one on the north, and the other on...
Página 187 - ... the squares of the periodic times are as the cubes of the distances from the common centre, the centripetal forces will be inversely as the squares of the distances.
Página 14 - ... invisible. These animals are of a great variety of shapes and sizes, and in such prodigious numbers, that, in a short time, the whole surface of the rock appears to be alive and in motion. The most common...
Página 2 - In experimental philosophy we are to look upon propositions collected by general induction from phenomena as accurately or very nearly true, notwithstanding any contrary hypotheses that may be imagined, till such time as other phenomena occur, by which they may either be made more accurate, or liable to exceptions.
Página 15 - ... mark ; but the coral sand and other broken remnants thrown up by the sea, adhere to the rock, and form a solid mass with it, as high as the common tides reach. That elevation, surpassed the future remnants, being rarely covered, lose their adhesive...
Página 14 - The most common worm is in the form of a star, with arms from four to six inches long, which are moved about with a rapid motion, in all directions, probably to catch food. Others are so sluggish, that they may be mistaken for pieces of the rock, and are generally of a dark colour, and from four to five inches long, and two or three round.