Evershed, M. A. (Orr) · London : Gall & Inglis · leaf 166
ptic. This may best be seen by takingtwo rings or hoops (two large curtain rings, forinstance), one of which just fits inside the other. Tiltthe inner ring, so that half of it is above and halfbelow the other ring, and they touch at two points,1 and 2 (Fig. 27). The outer ring is the Ecliptic,… … Fig. 2ti. The moveuieut of Earths axis, which is the truecause of Precession. V is the vernal equinox, at the intersection of the equator and plane of theecliptic: APX the earths axis, which always preserves the same inclination(2;U%) to the plane of the ecliptic. As AFX slowly revolves round 2 in…
Dante Alighieri, 1265-1321 · Astronomy
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