The Impetus of Water and Mutual Penetration of Jets
The stronger stream bends the weaker and carries it along its own course
Continuing the study of water striking water in the air, Leonardo notes that a jet is more powerful in motion the lower it issues from the vessel that held it. When two jets collide, the more powerful penetrates the weaker, twisting it and carrying with it all the water that falls upon it while the rest follows its natural course. Three vessel-and-jet diagrams run down the right margin, one bearing the Institut de France stamp.
On this page
The more powerful jet bends and carries the weaker
Of waters that strike one another in the air, the more powerful penetrates the less powerful, twisting it and carrying with it all the water that falls upon it, while the remainder follows its natural course. If the water pouring from vessel a b with the motion b c is struck by the water from vessel d e moving e f, the stream e f bends at the blow and continues along line f m together with b c, nothing of it falling along its original path.
Outlet height and the power of a jet
Water of equal thickness will be the more powerful in motion the lower it pours within the vessel from which it was enclosed. Here d e takes from a b without losing anything of itself.
Impetus of water in the air
The heading frames the whole page: the impetus of water in the air and the penetration of one stream by the other. It sets up the paired demonstrations that follow.