2 3 *

to Lecture XL ,

The Days are the next Part of

* Ih-v _

i!R e

These may be

(3; . We shall consider^ e d into Solar and Sidereal Days. The( e r Bay is that Space of Time which in-^ Cries between the Sun’s departing from

s;

^ °ne Meridian, and its Return to the

a >iii

again -

But a Sidereal Day is theof Time which happens between theto * f^re of a Star from and its ReturnOf fame Meridian again. And eacho f ^ e fe are divided into 24 equal Parts,

ours.

Because the Diurnal Motion of the11 about its Axis is equable, every Revo

Mi,

0ri Will be performed in the lame Time ;

^Wefore all the Sidereal Days, and thes °f those Days, will be equal. AndMe ^ other hand, the Solar Days are alland that on two Accounts, viz.0 ^. Ufe °f the Elliptic Figure of the Earth’sand because of the Obliquity of theto the Equator.

tie (-f' iMis will appear as follows. Let 8Me r? ^ Un > AB a Part of the Ecliptic, AMM entre of the Earth, and M D a Me-N 0v ^, w hose Plane passes through the Sun.t s the Time of one Revolution aboutf XlS ’ * et the Earth be carried about thero m A to B, and then the MeridianQ^4 will

PlateLXIV.Fig. 4.