Search in Florence for the Ramondina.

Why the falling thing rebounds between equal angles.

The earth stands beneath the water as a body heavier than it, and the water does not weigh upon that earth nor press its bounds, because that part of the earth which is more liquid is more mixed with the water and shares more in that water; and that part of the earth which is more mixed with the water shares more in that water, whereby it becomes lighter and more like it, like the water, and lighter than that other earth which is mixed with less water.

Let the water be let fall around the circle of a b.

That thing will descend with slower motion which has the greater resistance.

There are two qualities of the elements, namely rare and dense; rare is said of fire, air and water; dense can be said only of earth.

There are two quantities of each element, namely continuous and discontinuous.

There are two quantities of the elements that move, namely continuous and discontinuous.

There are two natural motions of the continuous and discontinuous element, namely the motion of elevation and the motion of declination.

There are two figures that the elements make in fleeing discontinuously one from another.

Two there are when the elements continuously flee one from another.

There are two motions that the elements make in fleeing one from another.

There are two causes why one element flees from another.

The lighter the element, the longer its motion will be in fleeing from the element that encloses it.

Never will the element of fire show heaviness in earth, nor lightness, as air and water do, the one and the other accident; for if air goes into fire it acquires heaviness, and if it goes into water it acquires lightness; and so water entering into the air acquires heaviness, and entering into the earth, the earth falls out of that water.

No part of an element weighs within its own element.

The descent that water makes through the air will never be straight.

The motion that air makes in rising through water, whether continuous or discontinuous, will never be straight.

The motion that earth makes through water will partake the more of the straight the more it has of the continuous, and conversely will partake the more of the curved the more it has of the discontinuous.