2lS

ON THE EQUATION OF TIME.

Apogee, and not the distance he has to go toit, though it be ever so little, is called his meanAnomaly; and is always reckoned in signs, de-grees, minutes, &c. allowing thirty degrees toa sign. Thus, for example, when the fun hasgone a hundred and seventy-four degrees fromhis apogee at A, he, is said to be live signs,twenty-four degrees from it, which is his meananomaly. And, in like manner, when he hasgone three hundred and fifty-five degrees fromhis apogee, he is said to be eleven signs, twenty-five degrees from it; although he be but fivedegrees short of A, in coming round to it again.

So that from what has been said, it appears,that when the fun’s anomaly is less than sixsigns, that is, when he is any where between Aand C, in the half of his orbit ABC, the solarnoon will precede the clock noon: but whenhis anomaly is more than six signs, that is, whenhe is any where between C and A, in the halfof his orbit C D A, the clock noon will precedethe solar noon. On the contrary, when hisanomaly is o signs o degrees, that is, when he isin his apogee at A; or, when it is exactly sixsigns, which is when he is in his perigee at G,he will come to the meridian at the fame timewith the star, and it will be noon by them bothat the fame instant.

The obliquity of the ecliptic to the equator,which is the first mentioned cause of the equa-