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CONTENTS
OF
THE SYSTEM OF THE WORLD.
| That the matter of the heavens is fluid, | 511 |
| The principle of circular motion in free spaces, | 512 |
| The effects of centripetal forces, | 512 |
| The certainty of the argument, | 514 |
| What follows from the supposed diurnal motion of the stars, | 514 |
| The incongruous consequences of this supposition, | 514 |
| That there is a centripetal force really directed to the centre of every planet, | 515 |
| Centripetal forces decrease in duplicate proportion of distances from the centre of every planet, | 516 |
| That the superior planets are revolved about the sun, and by radii drawn to the sun describe areas proportional to the times, | 517 |
| That the force which governs the superior planets is directed not to the earth, but to the sun, | 518 |
| That the circum-solar force throughout all the regions of the planets decreaseth in the duplicate proportion of the distances from the sun, | 519 |
| That the circum-terrestrial force decreases in the duplicate proportion of the distances from the earth proved in the hypothesis of the earth s being at rest, | 519 |
| The same proved in the hypothesis of the earth's motion, | 520 |
| The decrement of the forces in the duplicate proportion of the distances from the earth and planets, proved from the eccentricity of the planets, and the very slow motion of their apses, | 520 |
| The quantity of the forces tending towards the several planets : the circum-solar very great, | 521 |
| The circum-terrestrial force very small, | 521 |
| The apparent diameters of the planets, | 521 |
| The correction of the apparent diameters, | 522 |
| Why the density is greater in some of the planets and less in others; but the forces in all are as their quantities of matter, | 524 |
| Another analogy between the forces and bodies, proved in the celestial bodies, | 525 |
| Proved in terrestrial bodies, | 525 |
| The affinity of those analogies, | 526 |
| And coincidence, | 526 |
| That the forces of small bodies are insensible, | 527 |
| Which, notwithstanding, there are forces tending towards all terrestrial bodies proportional to their quantities of matter, | 528 |
| Proved that the same forces tend towards the celestial bodies, | 528 |
| That from the surfaces of the planets, reckoning outward, their forces decrease in the duplicate, but, reckoning inward, in the simple proportion of the distances from their centres, | 529 |
| The quantities of the forces and of the motions arising in the several cases, | 529 |
| That all the planets revolve about the sun, | 529 |
| That the common centre of gravity of all the planets is quiescent. That the sun is agitated with a very slow motion. This motion defined, | 531 |
| That the planets, nevertheless, are revolved in ellipses having their foci in the sun; and by radii drawn to the sun describe areas proportional to the times, | 531 |
| Of the dimensions of the orbits, and of the motions of their aphelions and nodes, | 532 |
| All the motions of the moon that have hitherto been observed by astronomers derived from the foregoing principles, | 532 |
| As also some other unequable motions that hitherto have not been observed, | 533 |
| And the distance of the moon from the earth to any given time, | 533 |
| The motions of the satellites of Jupiter and Saturn derived from the motions of our moon, | 534 |
| That the planets, in respect of the fixed stars, are revolved by equable motions about their proper axes. And that (perhaps) those motions are the most fit for the equation of time, | 534 |
| The moon likewise is revolved by a diurnal motion about its axis, and its libration thence arises, | 535 |
| That the sea ought twice to flow, and twice to ebb, every day; that the highest water must fall out in the third hour after the appulse of the luminaries to the meridian of the place, | 535 |
