Avis des internautes - Rédiger un commentaire
Aucun commentaire n'a été trouvé aux emplacements habituels.
Autres éditions - Tout afficher
action altitude amount angle angular angular velocity appear arise ascertained astronomical atmosphere attraction axis body calculation called cause celestial CHAP circle clock comet described determined difference dimensions direction disc distance disturbing force diurnal motion double stars earth earth's surface ecliptic effect ellipse equal equator equinoctial equinox error exact exactly excentricity figure fixed globe gravity heavens heliocentric hemisphere horizon inclination inequality instance instrument interval J. C. Loudon Jupiter latitude latter length light longitude lunar magnitude mass mean measure meridian moon moon's nature 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 204 - Capricorn; because the sun, at the respective solstices, is situated in the division, or signs of the ecliptic so denominated. Of these signs there are twelve, each occupying 30° of its circumference. They commence at the vernal equinox, and are named in order — Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricornus, Aquarius, Pisces.
Page 236 - 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 287 - Jupiter a moderate-sized orange, in a circle nearly half a mile across; Saturn a small orange, on a circle of four-fifths of a mile...
Page 394 - This earth ? reciprocal, if land be there, Fields and inhabitants. Her spots thou seest As clouds, and clouds may rain, and rain produce Fruits in her soften'd soil, for some to eat 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 395 - Thus a yellow colour predominating in the light of the brighter star, that of the less bright one in the same field of view will appear blue ; while, if the tint of the brighter star verge to crimson, that of the other will exhibit a tendency to green — or even appear as a vivid green, under favourable circumstances.
Page 211 - 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 those of terrestrial magnetism and the aurora.
Page 8 - ... that central thread of common sense on which the pearls of analytical research are invariably strung; but which, by the attention the latter claim for themselves, is often concealed from the eye of the gazer, and not always disposed in the straightest and most convenient form to follow by those who string them.
Page 233 - That 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, 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...