A high-school astronomy: in which the descriptive, physical, and practical are combined .. (1859)
Mattison, Hiram, 1811-1868 · New York, Mason brothers · leaf 85
by long andcareful observationthat the earth reachesthe equinoctial pointabout 22 minutesand 23 seconds ear-lier every year thanon the year preced-ing. This is equalto 50J of arc in theecliptic. In thismanner the equinoc-tial points are slowlyreceding westward, 157. What said of the orbits of… … PRECESSION OF THE EQUINOXES. 81 or falling back upon the ecliptic, at the rate of 50} ayear, or 1° every 71f years. This would amount to 80°,or one whole sign in 2,140 years, and to the entire circleof the ecliptic in 25,868 years. This very interesting phenomenon may be explained by the preceding…
Astronomy
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![An illustration from Cosmographia in qvatvor libros distribvta summo ordine, miraqve facilitate, ac breuitate ad magnam Ptolemæi mathematicam constructionem, ad vniuersamque astrologiam institutens. Francisco Barocio ... avtore. Cum præfatione eiusdem autoris, in qua perfecta quidem astrologiæ diuisio, & enarratio autorum illustrium, & voluminum ab eis conscriptorum in singulis astrologiæ partibus habetur: Joannis de Sacrobosco verò 84 errores, et alij permulti suorum expositorum, & sectatorum ostenduntur. rationibusq[uam] redarguuntur. Præcesserunt etiam quædam communia mathematica, necnon arithmetica, & geometrica principia, nonnullæq[uam] propositiones, de quibus in toto opere sæpe fit mentio: ac demum locupletissimus index eorum, quæ ipsa Cosmographia continentur .. (1585)](https://img.insideoutlibrary.com/img/200/ia-cosmographiainqv00baro-160-63.webp)
