^el 0l

Here

^*i$

Astronomy.

,Clt y till it arrives at the Aphelion Point,

moves {lowest of all;

20 X

and fromthence

Ecliptic, P S the Axis of the Equator or of^ e Lr ■’ ^ anc * ^ the North and South Poles ; besides^'Jie s r0p h s an d Polar Circles, here represented by Right^derfl 35 the common Analemma. And by those who

a ^d this! Prriio/O-i^’T flip Trifle of th si ond

. -r> . n.- ^ fVp Disk of the Earth andof she J Shadows over it tray be exhibitedh ace °f the Sun,

^ Vifse ur tne dun, or Declination of the Moon ;• 26. £ ^ ee my Young Trigonometer’s Guide, Vol. II.o Ph e Eclipses are not quite so complicated

f l0 h nor near so tedious and difficult in Calc da-r °,! ar ones. The latter are only apparent, theJ its s uc ^ ; that is, the Moon is really deprivedb ^ st hah' ’ therefore must appear obscured to allsheen - ltantS of the Earth equally, by whom she can.11 ev e ’ V 'Eereas the Sun, not being deficient in Light,Sb* 5 to f a ^P ear !e fpiendent to the le who do not hap-V,‘ Ve on that Part of the Earth where the Lunar2 ), '^PTs.

s a Lunar Eclipse is occasioned by the Itn-A t 0c , t ' le Moon into the Earth’s Shadow, we have3do V/ a c nlate the apparent Semkliameter of the Earth’sa t hi s p at the Moon, in order to delineate an Eclipset Thus let A B be the Earth, T its Centre,

Jj Conical Shadow, D C the Diameter of a■^the ^teof at the Moon ; and drawing TD, we

PI. LNI,Pig- 4 -

outward Angle ADT=DTE+DET;

^gle r £ D T E-AD T — D E T ; that is, theN r t(i’ s g, ■*■ E, under which the Semidiaipeter of the, e tjn 9 j hadow at the Distance of the Moon appears,s Qri tn! p to the Difference between the Moon’s Hori-4,1 D ]£p'* ax ^ D T, and the Semi diameter of the

^ 8 , j/* . *

v *■ ere fore A E represent the Path of the Earth’st|] EfJ p 16 distance of the Moon near the Node q,Ea.-th’ art of the Lunar Orbit, and the Sedlion of' e fEll.iVfhadQw be delineated at &, B, C, D, and

• ,°°n at S , I 3 N, G ; then *tis evident, where

the

fig.