Of these the more noteworthy dealt with the distribution of stars, starclusters and nebulae, and the construction of the sidereal universe.
Their sidereal year was 4zm too long, s and they kept the ecliptic stationary among the stars, making no allowance for the shifting of the equinoxes.
In this remarkable work Kant, proceeding from the Newtonian conception of the solar system, extends his consideration to the entire sidereal system, points out how the whole may be mechanically regarded, and throws out the important speculation which has since received the title of the nebular hypothesis.
The eye end presents an refractor appearance too complicated to be figured here; it has a micrometer and its illumination for the position circle, a micrometer head, and a bright or dark field, clamps in right ascension and declination and quick and slow motion in the same, a finder, microscopes for reading the hour and declination circles, an illuminated dial showing sidereal time and driven by an electric current from the sidereal clock, and counter weights which can be removed when a spectroscope or other heavy appliance is added.
Hence if the earths axis of rotation deviates slightly from the axis of figure, it should describe a cone about the latter in 320 sidereal days.
Among the most representative are: the Popular Science Monthly, New York; the monthly Boston Journal of Education; the quarterly American Journal of Mathematics, Baltimore; the monthly Cassier's Magazine (1891), New York; the monthly American Engineer (1893), New York; the monthly House and Garden, Philadelphia; the monthly Astrophysical Journal, commenced as Sidereal Messenger (1882), Chicago; the monthly American Chemical Journal, Baltimore; the monthly American Naturalist, Boston; the monthly American Journal of the Medical Sciences, Philadelphia; the monthly Outing, New York; the weekly American Agriculturist, New York; the quarterly Metaphysical Magazine (1895) New York; the bi-monthly American Journal of Sociology, Chicago; the bi-monthly American Law Review, St Louis; the monthly Banker's Magazine, New York; the quarterly American Journal of Philology (1880), Baltimore; the monthly Library Journal (1876), New York; the monthly Public Libraries, Chicago; Harper's.
Hipparchus fixed the chief data of astronomy - the lengths of the tropical and sidereal years, of the various months, and of the synodic periods of the five planets; determined the obliquity of the ecliptic and of the moon's path, the place of the sun's apogee, the eccentricity of his orbit, and the moon's horizontal parallax; all with approximate accuracy.
While sharing the opinion of Tycho as to the origin of such bodies by condensation of nebulous matter from the Milky Way, he attached a mystical signification to the coincidence in time and place of the sidereal apparition with a triple conjunction of Mars, Jupiter and Saturn.
Owing to the precession of the equinoxes it is longer than a tropical or sidereal year by 25 minutes and 2.3 seconds.