It was considered by Biot to have been originally twenty-four, but to have been enlarged to twenty-eight about i ioo B.C., by the addition of determinants for the solstices and equinoxes of that period.
In The Arrangement Of The Civil Year, Two Objects Are Sought To Be Accomplished, First, The Equable Distribution Of The Days Among Twelve Months; And Secondly, The Preservation Of The Beginning Of The Year At The Same Distance From The Solstices Or Equinoxes.
KOXos, shortened, and ovpfi, tail), in astronomy, either of the two principal meridians of the celestial sphere, one of which passes through the poles and the two solstices, the other through the poles and the two equinoxes; hence designated as solstitial colure and equinoxial colure, respectively.
As to the astronomical knowledge of Thales we have the following notices: - (1) besides the prediction of the solar eclipse, Eudemus attributes to him the discovery that the circuit of the sun between the solstices is not always uniform; 6 (2) he called the last day of the month the thirtieth (Diog.
He taught, if he did not discover, the obliquity of the ecliptic, is said to have introduced into Greece the gnomon (for determining the solstices) and the sundial, and to have invented some kind of geographical map. But his reputation is due mainly to his work on nature, few words of which remain.
Already, in the third millennium B.C., equinoxes and solstices were determined in China by means of culminating stars.
In the other letters written in 1685 and 1686 he applies to Flamsteed for information respecting the orbits of the satellites of Jupiter and Saturn, respecting the rise and fall of the spring and neap tides at the solstices and the equinoxes, respecting the flattening of Jupiter at the poles (which, if certain, he says, would conduce much to the stating the reasons of the precession of the equinoxes), and respecting the difference between the observed places of Saturn and those computed from Kepler's tables about the time of his conjunction with Jupiter.