N. B. I propose the Five first as Arguments exceeding probable; but this last as a really certain Demonftration.

PROP. II.

The Annual Motion, or that which occafions the Succeffion of Summer and Winter, and the apparent Motion of the Sun through the Ecliptick, in the Space of 365 Days, which we call a Tear, belongs to the Earth, and not to the Sun.

DEMONSTRATION.

(1.) All the Phænomena or Appearances re lating to this Matter, are now certainly known to be equally natural and necessary Consequences of an Annual Revolution of the Earth, as of the Sun; as all Aftronomers confess. And he who confiders the prodigious Greatness of the Sun's Body, and the comparative Smallness of the Earth, will be under no Temptation to suppose that the vast Sun revolves round this little Earth; especially when he reflects, that all things will be the very fame, if this little Earth be suppos'd to revolve about that vast Sun in the fame time.

(2.) There are no known Laws of Motion according to which so great a Body as the Sun can revolve about so small a Body as the Earth; nay, this is directly contrary to all fuch known Laws whatsoever. For let the Occafion or Influence derived from these two Bodies be of what fort you please, either Gravitation, or Magnetism, or Impulse, &c. still the greater Body,

D

Body, as in all like Cafes, must have the greatest Force and Efficacy to move the other. And we may full as well expect that a Sling, containing a Milftone in it, may be fasten'd to a Pebble, and continue its Motion about that Pebble, without removing it, as that the Sun can revolve about our Earth, while the Earth continues immoveable in the Center of that Motion.

(3.) There is no Instance of such a thing in the visible World, as a great Body thus revolving about a small one, that continues it self immoveable all the while; but all the Instances are on the other side. The smaller Moon revolves about the larger Earth; the smaller Circumjovials and Circumsaturnals revolve about the larger Jupiter and Saturn; Saturn, Jupiter, Mars, Venus, and Mercury, revolve all, not about the smaller Earth, but about the larger Sun; as is now confefs'd by the whole Astronomical World; and as is certainly demonstrated by the Phases of Venus and Mercury seen See Fig. I. through a Telescope. And tho' in a strict Sense all these larger Bodies may be so far said to revolve about those smaller, as they may still, on both fides, revolve about the common Center of Gravity; yet because the common Center of Gravity of the Sun and Earth must be so very near the Center of the Sun, and so very far from the Center of the Earth; and by consequence, the Motion of the Sun, if compar'd with that of the Earth about it, must be so very insensible; it follows, that the most sensible Annual Motion, of which we are now speaking, must still, by all parallel Instances, belong to the Earth, and not to the Sun.

(4.) The

The Copernican, or true Solar System. Pag. 34

Saturn with his Ring and five Moons. "

Jupiter and his 4 Moons

Fig. I.

These

are

the three Famous Systems of Aftronomy In the Copernican the the Phases of Venus and Mercury, which are Full in one Conjunction with the Sun, when they are beyond it as s to to the the Earth, Earth Demonstrate 1 that y PtolemaickSystem in nhich that situation is impoßible, Nor is there the least evidence.

shens to

in

utterly falfe.

the

very Figure

the World for the Tychonick:which be absurd and monstrous: That the Valt Sun with its Prodigious System

of the Planets, should be as in as in the Copernican; and yet that this System of the Sun and Planets should all Revolve round this little Earth in a Years Years time!

I Senex foulp

2

(4.) The Hypothefis that this Annual Motion belongs to the Sun, and not to the Earth, introduces the utmost Confufion among the Celeftial Motions, and that without any proper occafion in the World. For what strange confusion is it for us to imagine that the single Earth, which is now confefs'd by all to be situate between Mars above, and Venus below it; while all the rest of the Planets, Saturn with his Satellites, Jupiter with his, and Mars, Venus, and Mercury, without any, do all revolve not about the Earth, but about the Sun; nay that the Superior revolve about it in longer, and the Inferior in shorter Periods or Years, while the Annual Period, is in a mean between them; that I say the single Earth be exempted from the common Law of the whole System? What a heap of Absurdities are here? That while all the rest of the Planetary World revolve about the Sun, in their several regular Periods or Years, that yet our Earth, contrary to all Probability, should be suppos'd to carry not the Sun only, but all the Solar System also round it self in a Year's time, as it certainly must, if the Annual Motion belong to the Sun? See Fig. II, This Hypothesis of the famous Tycho, which is the only one that is not absolutely impossible to be true, is yet so wild, groundless, and extravagant in it self, and so prodigiously improbable, that I should exceedingly wonder at its first Introduction, and much more at its Admission still in Roman-Catholick Countries, did I not know that Injudicious Persons have interpreted Scripture against the true System; and that an Infallible Church has Establish'd that Interpretation; nay, has condemn'd the true one