Chapter III: Book II

~CHAP. 1.~ _That the planets move in a space
empty of sensible matter_ p. 161
_The system of the world described_ p. 162
_The planets suffer no sensible resistance in their
motion_ p. 166
_They are not kept in motion by a fluid_ p. 168
_That all space is not full of matter without vacancies_ p. 169

~CHAP. 2.~ _Concerning the cause that keeps in
motion the primary planets_ p. 171
_They are influenced by a centripetal power directed to
the sun_ p. 171
_The strength of this power is reciprocally in the
duplicate proportion of the distance_ ibid.
_The cause of the irregularities in the motions of the
planets_ p. 175
_A correction of their motions_ p. 178
_That the frame of the world is not eternal_ p. 180

~CHAP. 3.~ _Of the motion of the moon and the other
secondary planets_
_That they are influenced by a centripetal force
directed toward their primary, as the primary are
influenced by the sun_ p. 182
_That the power usually called gravity extends to
the moon_ p. 189
_That the sun acts on the secondary planets_ p. 190
_The variation of the moon_ p. 193
_That the circuit of the moons orbit is increased by the
sun in the quarters, and diminished in the
conjunction and opposition_ p. 198
_The distance of the moon from the earth in the quarters
and in the conjunction and opposition is altered by
the sun_ p. 200
_These irregularities in the moon’s motion varied by the
change of distance between the earth and sun_ p. 201
_The period of the moon round the earth and her distance
varied by the same means_ ibid.
_The motion of the nodes and the inclination of the
moons orbit_ p. 202
_The motion of the apogeon and change of the
eccentricity_ p. 218
_The inequalities of the other secondary planets
deducible from these of the moon_ p. 229

~CHAP. 4.~ _Of comets_

_They are not meteors, nor placed totally without the
planetary system_ p. 230
_The sun acts on them in the same manner as on the
planets_ p. 231
_Their orbits are near to parabola’s_ p. 233
_The comet that appeared at the end of the year 1680,
probably performs its period in 575 years, and
another comet in 75 years_ p. 234
_Why the comets move in planes more different from
one another than the planets_ p. 235
_The tails of comets_ p. 238
_The use of them_ p. 243 244
_The possible use of the comet it self_ p. 245 246

~CHAP. 5.~ _Of the bodies of the sun and planets_

_That each of the heavenly bodies is endued with an
attractive power, and that the force of the same
body on others is proportional to the quantity of
matter in the body attracted_ p. 247
_This proved in the earth_ p. 248
_In the sun_ p. 250
_In the rest of the planets_ p. 251
_That the attractive power is of the same nature in
the sun and in all the planets, and therefore is
the same with gravity_ p. 252
_That the attractive power in each of these bodies is
proportional to the quantity of matter in the body
attracting_ ibid.
_That each particle of which the sun and planets are
composed is endued with an attracting power, the
strength of which is reciprocally in the duplicate
proportion of the distance_ p. 257

_The power of gravity universally belongs to all matter_ p. 259

_The different weight of the same body upon the surface
of the sun, the earth, Jupiter and Saturn; the
respective densities of these bodies, and the
proportion between their diameters_ p. 261

~CHAP. 6.~ _Of the fluid parts of the planets_

_The manner in which fluids press_ p. 264
_The motion of waves on the surface of water_ p. 269
_The motion of sound through the air_ p. 270
_The velocity of sound_ p. 282
_Concerning the tides_ p. 283
_The figure of the earth_ p. 296
_The effect of this figure upon the power of gravity_ p. 300
_The effect it has upon pendulums_ p. 302
_Bodies descend perpendicularly to the surface of
the earth_ p. 304
_The axis of the earth changes its direction twice a
year, and twice a month_ p. 313
_The figure of the secondary planets_ ibid.