Elements of Natural Philosophy

a₁ adjustment altitude angular distance axis azimuth B₂ body called celestial sphere centre circle of latitude computed conjunction corr cos² D₁ declination circle denote diameter diff difference direction disk diurnal diurnal motion earth east eclipse ephemeris equal equation equatorial equinoctial error formulæ geocentric give greatest Greenwich Greenwich mean heliocentric horizon horizontal parallax hour angle hourly motion inclination instrument latitude latter limb limits line of collimation longitude lunar M₁ mean distance meridian moon moon's node object observation parallactic parallel pass perihelion perpendicular phase plane polar distance pole position proper motion radius vector reading reduced refraction right ascension satellites screws shadow side sidereal sidereal day sin² solar solar eclipse star sun's telescope tion transit triangle true true anomaly vernal equinox vernier whence wires zenith distance ΙΟ