pL On the new Theory 
ing on and through the medium of space upon the planetary 
bodies, or upon any aggregations of matter, would propel them 
into correspouding motions, with forces varying reciprocally as 
the squares of the distances, and directly as the quantities 
of matter to be moved. Hence the orbicular’ motions of the 
planets*. 
If the result of this action were a balance of momenta in the 
moving bodies, as directly exerted and dissipated in the medium of 
space, then the or bicular motion would terminate the phenomena3. 
but, if the continuous mass of the planetary body were unequally 
acted upon, owing to its sides being of different density, then 
the equal action of the prime mover would drive the lighter 
hemisphere round the heavier (as the Pacific Ocean round the 
old Continent); and a rotary motion would necessarily be ge- 
nerated, whose axis would equalize the quantities of matter on 
each of its sides. 
- Of course such an action, constantly exerted on various bodies 
distributed through space, would cause them to vary their re- 
spective motions, according to their positions in relation to each 
ather; because the force on each would be as their mutual po- 
sitions in regard to the sun.— Hence the mutual disturbances of 
the uniform motions of the planets. 
The motion thus created in every mass would, from a like cause, 
occasion each to act on the other, in proportion to its bulk and 
quantity of matter. The earth and moon would be acted upon 
by the sun; but the earth would also act upon the moon, more 
than the moon upon the earth, in the proportion of their matter. 
The common action of the sun on both would occasion them of 
necessity to endeavour to turn on the centre of the quantity of 
motion generated by each.— Hence the revolution of small masses 
round large ones. 
But, as the secondary planets would be governed chiefly and 
proximately by their primaries, and these would possess a power 
of varying the centre of motion by the motion of their fluids, 
which would, from that cause, rise in the parts presented to the 
secondary; so the secondary would not turn on the centre of its 
own mass, but its disposition to do so would be destroyed by the 
varying or accommodating energies of the primary.— Hence the 
peculiar motions of a secondary planet, and the necessary con~ 
nexion of those motions with the tides of the primary. 
Of course also, as the axis of each mass, or of the joint masses 
of primaries and secondaries, would be constantly turning round 
the physical axis or centre balancing their quantity of motion, 
* Tf the velocities were as the forces exerted, and the momenta were as 
the matter compounded of the square of the velocities, then the quantities 
of motion at each end of the line of action would in theory be equal. d 
an 
