196

PI. LX.

pS- 5 -

Astronomy.

Contrivance by elliptical Wheels is R ece ^ jto effect it; of which we have

Moon were always in the fame Plane, therecessarily be an Eclipse of the Sun every timecame between the Sun and Earth, that is, at eV 5 shG^Moon. For let X be the Sun, T the Earth, and y ^ci*the Moon’s Orbit in the Plane of the Eclip t] ^’when the Moon comes to be at B in the Fd& cP'TX, which joins the Centres of the Sun aJ1 , Sp eC ^it will be exactly interposed between the Sun an a ^tat or on the Earth at V ; and smee the appar 611 .^ ^nitude or Disk of the Sun is the same nearly Pa^of the Moon, it must necessarily be hid behind 41 .fd 1Disk at that Time, and so eclipsed from the S>g‘ ^ 1$Spectator ; and this must be the Cafe when®J ei c<lMoon comes into the said Line or Point B, vt% 'New Moon. 0 (<K

11. But if (as the Case really is) the Orct.^jjji^Moon he not in the Plane of the Ecliptic, but sthereto under a certain Angle, there may be f#Moon, and yet no Eclipse of the Sun at 1Time. To illustrate this, let A B C D E E® ,^ a n cin the Plane of the Ecliptic, described at the sitf 1of the Moon’s Orbit AGH, and intersecting * ;tbin the Points B and D, making an Angle thet e

A B F, whose Measure is the Arch G C, j w 1

90 Degrees distant from the angular PointsB and D. f n tf e n{

12. Now ’tis evident, if the Arch G C p ,

neater than the Sum of the apparent Semid* 3 e fs° ^he Sun and Moon then at G, and some Dm^ ygt

G towards B, there may be a New Moon, ^4, of*',

the

Eclipse of the Sun, because in this Cafe theMoon G is too much elevated or depressed

Ct°

co

a*

__tx_ A. viV- » ULvU \J I

below the apparent Disk or Face of the Sun ~ r.it, much less to hide or eclipse any Part there >evident from the Figure. tzS

13. At a certain Point M in the Moon’s u J vMoon will have a Latitude equal to they u .^ 3 ^ {<