CHAP. XXXI.
On Long and Round Stones.
ieces of iron join more firmly with a long stone than with a round one, provided that the pole of the stone is at the extremity and end of its length; because, forsooth, in the case of a long stone, a magnetick is directed at the end straight towards the body in which the virtue proceeds in straighter lines and through the longer diameter. But a somewhat long stone has but little power on the side, much less indeed than a round one. It is demonstrable, indeed, that at A and B the coition is * stronger in a round stone than at C and D, at like distances from the pole.
CHAP. XXXII.
Certain Problems and Magnetick Experiments about
the Coition, and Separation, and regular Motion
of bodies magnetical.
qual loadstones come together with equal incitation. *
Also magnetick bodies of iron, if alike in all respects, * come together when excited with similar incitation.
Furthermore, bodies of iron not excited by a * loadstone, if they are alike and not weighed down by their bulk, move towards one another with equal motion.
Two loadstones, disposed on the surface of some water in suit-able
