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Pàgina 36 - A singular law obtains among the mean motions and mean longitudes of the first three satellites. It appears from observation that the mean motion of the first satellite, plus twice that of the third, is equal to three times that of the second ; and 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. It is proved by theory, that if these relations had only been...
Pàgina 399 - ... the firmament of large stars, into which the central cluster would be seen projected, and (owing to its greater distance) appearing like it to consist of stars much smaller than those in other parts of the heavens. "Can it be,'' asks Sir J. Herschel, " that we have here a brother system, bearing a real physical resemblance and strong analogy of structure to our own ?
Pàgina 2 - The heavens afford the most sublime subject of study which can be derived from science. The magnitude and splendour of the objects, the inconceivable rapidity with which they move, and the enormous distances between them, impress the mind with some notion of the energy that maintains them in their motions, with a durability to which we can see no limit. Equally conspicuous is the goodness of the great First Cause, in having endowed man with faculties, by which he can not only appreciate the magnificence...
Pàgina 421 - The circumference of every circle is supposed to be divided into 360 equal parts called degrees, and each degree into 60 equal parts called minutes, and each minute into 60 equal parts called seconds, and these into thirds, fourths, &c.
Pàgina 28 - Omnipotent, and with his words All seem'd well pleas'd ; all seem'd, but were not all. That day, as other solemn days, they spent In song and dance about the sacred hill ; Mystical dance, which yonder starry sphere Of planets, and of fix'd, in all her wheels Resembles nearest, mazes intricate, Eccentrick, intervolv'd, yet regular, Then most when most irregular they seem ; And in their motions harmony divine So smooths her charming tones, that God's own ear Listens delighted. Evening now approach'd...
Pàgina 25 - But, in the midst of all these vicissitudes, the length of the major axes and the mean motions of the planets remain permanently independent of secular changes. They are so connected by Kepler's law, of the squares of the periodic times being proportional to the cubes of the mean distances of the planets from the sun, that one cannot vary without affecting the other.
Pàgina iii - If I have succeeded in my endeavour to make the laws by which the material world is governed, more familiar to my countrywomen, I shall have the gratification of thinking, that the gracious permission to dedicate my book to your Majesty has not been misplaced.
Pàgina 256 - ... miles in a second — a fragment of it alone reached the earth. The obliquity of the descent of meteorites, the peculiar substances they are composed of, and the explosion accompanying their fall, show that they are foreign to our system.
Pàgina 51 - The variation, therefore, in the distances of the sun and moon from the centre of the earth, and of the moon from her node at the instant of conjunction, occasions great varieties in the solar eclipses. Besides, the height of the moon above the horizon changes her apparent diameter, and may augment or diminish the apparent distances of the centres of the sun and moon, so that an eclipse of the sun may occur to the inhabitants of one country, and not to those of another. In this respect the solar...
Pàgina 213 - The spritsail yard and mizen boom w«re lighted by the reflection, as if gas lights had been burning directly below them; and until just before daybreak, at four o'clock, the most minute objects were distinctly visible. Day broke very slowly and the sun rose of a fiery and threatening aspect. Rain followed.