. Sea. I. Of the SOLAR SYSTEM.

if visible, appears horned} that Face ofhers which is towards the Sun, is eitherwholly turned from the Earth, or only asmall Part of it can be seen by the Earth ;and in this cafe she must of necessity bebetwixt us and the Sun. Let S be the Sun,T the Earth, and V Ferns, having thesame Face presented both towards the Sunand Earth: Here it is plain, that the Sun isbetwixt us and Venus, and therefore we musteither place Venus in an Orbit round the Sun,and likewise betwixt him and us, as in Fig.i. or else we must make the Sun to moveround the Earth in an Orbit within thatof Venus, as in Fig. 2. Again, after Ve-nus disappears, or becomes horned, at her* </ with the D, slie then must be betwixtus and the Sun, and must move either inan Orbit round the Sun, and betwixt us andhim, as in Fig. 1. or else round the Earth,and betwixt us and the Sun, as in Fig. 2.But Venus cannot move sometimes withinthe Sun’s Orbit, and sometimes without it,as we must suppose, if she moves round theEarth} therefore it is plain that her Motionis round the Sun.

Besides the foregoing; there is another Ar-gument to prove that Venus turns round theSun, in an Orbit that is within the Earth’s;because the is always observed to keep near

the

* rf Is a Mark commonly used for Conjunction: Thuswith the ®, is to be read Conjunction with the Sun.

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Plate r.Fig. i. 2.