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according amount angle angular appear ascertained astronomers axis body called cause celestial centre changes circle comet complete constellation course Describe determined diameter difference direction discovered disk distance earth east eclipse entire equal equator exist Explain extent fact figure fixed force four Give given globe Grammar greater half heavens hemisphere Herschel horizon hundred illumination illustrated inclination known Latin latitude latter length less light lunar magnitude manner mean measured meridian miles minutes months moon moon's motion mountains move nature nearly night nodes observations obtained occur opposite orbit parallax passing perihelion period planet pole position present Prof proved quarter refraction regard represents respecting revolve ring rotation round School seen shadow side solar solstice space stars sun's supposed surface telescope termed tides tion true vernal equinox visible zenith
Page 296 - The fourth term is found by multiplying the second and third terms together and dividing by the first § 14O.
Page 164 - These phenomena do not, however, occur at every new and full moon ; and the reason is, that the plane of the moon's orbit is inclined to that of the ecliptic, and that these two planes' meet one another only in their line of common section, which passes through the centre of the earth.
Page 305 - On a careful re-examination of the heavens, too, and a comparison of catalogues, many stars are now found to be missing-; and although there is no doubt that these losses have often arisen from mistaken entries, yet in many instances it is equally certain that there is no mistake in the observation or entry, and that the star has really been observed, and as really has disappeared from the heavens...
Page 24 - A SPHERE is a solid bounded by a curved surface, every part of which is equally distant from a point within, called the centre.
Page 162 - In some of the principal ones, decisive marks of volcanic stratification, arising from successive deposits of ejected matter, and evident indications of Lava currents streaming outwards in all directions, may be clearly traced with powerful telescopes.
Page 13 - Dodd, I find it greatly superior to all others which have come under my notice, in system, completeness, and nomenclature. The arrangement is natural, the system complete, and the nomenclature greatly improved. These improvements are not slight; they are fundamental— eminently worthy the attention of the mathematical teacher, and give a character of unity to the work which at once distinguishes it from all others on this subject.
Page 50 - ... the sun. More Accurate Computations. — A more accurate determination of the phases as visible at any point of the earth's surface may be obtained from the Besselian elements which are given for every ten minutes of Greenwich mean time. Their geometric signification is as follows: — Let us imagine a plane passing through the centre of the earth, perpendicular to the right line joining the centres of the sun and moon. This latter line is the axis of the moon's shadow, and the plane is called...
Page 51 - Circles are great circles passing through the zenith of an observer, and perpendicular to his horizon. The vertical circle passing through the east and west points of the horizon is called the Prime Vertical ¡ that passing through the north and south points coincides with the celestial meridian.
Page 318 - This is an irresolvable nebula, figured by Sir John Herschel, during his residence at the Cape of Good Hope. Its favourable position, as seen in southern latitudes, enabled Herschel to trace the outline of the nebula much farther than any preceding observer had done. The singular figure of this object seems to suggest some power of attraction operating on the particles of matter, or the...