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ſaid to riſe: the ſame way the Weſtern Horizon doth elevate itſelf above thoſe bodies that are the moſt Weſtern, and they are ſaid to ſet; and so thoſe bodies, that are on the eaſtern ſide of the Meridian, will, by this motion of the Earth, culminate, or tranſit the Meridian, and in turn will ſet; as alſo the imaginary Circles of the Sphere, ſuch as the Equinoctial, the Ecliptic with the Sun, and Planets therein, will, by the rotation of the Earth, all appear to riſe, culminate and ſet, cauſing day and night to all; this is called the Diurnal, and Horary Motions of the Spheres; this is the part of Aſtronomy that is peculiarly noticed by, and uſeful to every one; it is theſe motions, that my Planisphere is chiefly intended to illuſtrate, and render familiar to the capacity and practice of every Lover of Aſtronomy; and this leads me to the following Precepts, on the Properties and Uſes of the Circles of the Planisphere.
Precept 1. Declination of the Celestial Bodies, is an Arc of the Meridian, beginning at the Equinoctial, and counting it North and South to the Poles, ſo any celeſtial object, while it is ſituated on the North ſide of the Equinoctial, is ſaid to have North Declination; but, while they are on the South ſide of the Equinoctial, are ſaid to have South Declination; and note! on my Planisphere, a Scale of Declination, North and South, is laid down upon the Meridian of the Index with 0° degrees, revolving in the Equinoctial.
Precept 2. Right Ascension in Time, and Degrees, is an Arc of the Equinoctial, beginning at the firſt
