The Elements of Astronomy: A Text-book

altitude angle astronomical astronomical units atmosphere axis azimuth bright Cassiopeia celestial equator celestial sphere centre circle comet constellation corona dark declination density determine disc Dist distance Double Stars earth earth's orbit earth's surface east eclipse equal equatorial eye-piece feet force globe gravity heat heavenly bodies heliometer horizon inches instrument Jupiter known latitude libration light longitude lunar lunar eclipse magnitude Mags mass mean measured meridian meridian circle meteoric method miles minutes moon moon's motion moving naked eye nearly nebula node object object-glass observations parallax perihelion period perturbations photosphere planet pole Pole-star position probably radius right ascension ring rotation satellite seen shadow sidereal sidereal period Sirius solar spectroscope spectrum star's Sun Spots sun's surface synodic synodic period telescope tide tion transit Uranus velocity Venus vernal equinox visible zenith