Equal weights at equal distances are in equilibrium and equal weights at unequal distances are not in equilibrium but incline towards the weight which is at the greater distance.
ArchimedesThe diameter of the earth is greater than the diameter of the moon and the diameter of the sun is greater than the diameter of the earth.
ArchimedesI am persuaded that this method [for calculating the volume of a sphere] will be of no little service to mathematics. For I foresee that once it is understood and established, it will be used to discover other theorems which have not yet occurred to me, by other mathematicians, now living or yet unborn.
Archimedes