993

Other problems.

You now have to prove that the shells cannot have originated if not in salt water, almost all being of that sort; and that the shells in Lombardy are at four levels, and thus it is everywhere, having been made at various times. And they all occur in valleys that open towards the seas.

Taken from The Notebooks of Leonardo da Vinci edited by Jean Paul Richter, 1880.

Notebooks of Leonoardo da Vinci

XVI: Physical Geography.

. . .

973,

Whirlpools.

On the alterations in the channels of rivers.

The origin of the sand in rivers.

977,

The formation of mountains.

979,

980,

981,

982,

The authorities for the study of the structure of the earth.

984,

Doubts about the deluge.

That marine shells could not go up the mountains.

The marine shells were not produced away from the sea.

Further researches.

989,

990,

Other problems.

992,

993,

Constituents of the atmosphere.

On the motion of air.

996,

997,

998,

The globe an organism.