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altitude amount angle angular appear arise ascertained astronomical atmosphere attraction axis bright calculation called cause celestial centre centrifugal force circle clock comet course degree described determined deviation diameter difference direction disc distance disturbing force diurnal motion double stars earth earth's surface eccentricity ecliptic effect ellipse equal equator equinoctial equinox error exact exactly fixed globe gravity heavens heliocentric hemisphere horizon inclination instance instrument interval Jupiter latitude latter law of Kepler length less light longitude lunar magnitude mass mean measure meridian moon moon's nearly nodes nutation object observed orbit parallax perihelion period planet planetary pole portion position precession produce proportion radius reckoned refraction respect retrograde revolution revolving right ascension ring rotation round satellites Saturn seen sidereal sidereal period situation solar spectator sphere spherical stars station sun's suppose synodical period telescope tion triangle Uranus variation velocity visible whole zenith
Page 195 - They commence at the vernal equinox, and are named in order — Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricornus, Aquarius, Pisces.* They are denoted also by the following symbols : — T, «, n, ©, SI, nji, &, m., /, Yf, :::, x. Longitude itself is also divided into signs, degrees, and minutes, &c. Thus 5* 27° 0
Page 225 - that every particle of matter in the universe attracts every other particle, with a force whose direction is that of the line joining the two, and whose magnitude is directly as the product of their masses, and inversely as the square of their distances from each other.
Page 201 - ... efficiency which are laid up for human use in our coal strata. By them the waters of the sea are made to circulate in vapour through the air, and irrigate the land, producing springs and rivers. By them are produced all disturbances of the chemical equilibrium of the elements of nature, which by a series of compositions and decompositions, give rise to new products, and originate a transfer of materials.
Page 222 - ... immediate consciousness of effort, when we exert force to put matter in motion, or to oppose and neutralize force, which gives us this internal conviction of power and causation so far as it refers to the material world, and compels us to believe that whenever we see material objects put in motion from a state of rest, or deflected from their rectilinear paths, and changed in their velocities if already in motion, it is in consequence of such an EFFORT somehow exerted, though not accompanied...
Page 11 - Admission to its sanctuary, and to the privileges and feelings of a votary, is only to be gained by one means, a sound and sufficient knowledge of Mathematics, the great instrument of all exact inquiry, without which no man can ever make such advances in this or any other of the higher departments of science, as can entitle him to form an independent opinion on any subject of discussion within their range.
Page 368 - Allotted there; and other suns perhaps, With their attendant moons, thou wilt descry, Communicating male and female light, Which two great sexes animate the world, Stored in each orb perhaps with some that live.
Page 201 - The sun's rays are the ultimate source of almost every motion which takes place on the surface of the earth. By its heat are produced all winds, and those disturbances in the electric equilibrium of the atmosphere which give rise to the phenomena of lightning, and probably also to terrestrial magnetism and the aurora.
Page 221 - It is our own immediate consciousness of effort, when we exert force to put matter in motion, or to oppose and neutralize force, which gives us this internal conviction of power and causation, so far as it refers to the material world...
Page 201 - Tidal action (itself partly due to the sun's agency) exercises here a comparatively slight influence. The effect of oceanic currents (mainly originating in that influence), though slight in abrasion, is powerful in diffusing and transporting the matter abraded ; and when we consider the immense transfer of matter so produced, the increase of pressure over large spaces in the bed of the ocean, and diminution over corresponding portions of the land, we are not at a loss to perceive how the elastic...
Page 352 - Herschel, whose powerful telescopes first effected a complete analysis of this wonderful zone, and demonstrated the fact of its entirely consisting of stars. * So crowded are they in some parts of it, that by counting the stars in a single field of his telescope, he was led to conclude that 50000 had passed under his review in a zone two degrees in breadth, during a single hour's observation.