981

The formation of mountains.

The summits of mountains for a long time rise constantly.

The opposite sides of the mountains always approach each other below; the depths of the valleys which are above the sphere of the waters are in the course of time constantly getting nearer to the centre of the world.

In an equal period, the valleys sink much more than the mountains rise.

The bases of the mountains always come closer together.

In proportion as the valleys become deeper, the more quickly are their sides worn away.

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

Notebooks of Leonoardo da Vinci
XVI: Physical Geography.
. . .
Theory of the circulation of the waters.
961,
962
Observations in support of the hypothesis.
963,
964,
965,
966,
967,
968,
969
On the way in which the sources of rivers are fed.
970
The tide in estuaries.
971
confluence.
972,
973,
974
Whirlpools.
975
On the alterations in the channels of rivers.
976
The origin of the sand in rivers.
977,
978
The formation of mountains.
979,
980,
981,
982,
983
The authorities for the study of the structure of the earth.
984,
985
Doubts about the deluge.
986
That marine shells could not go up the mountains.
987
The marine shells were not produced away from the sea.
988
Further researches.
989,
990,
991
Other problems.
992,
993,
994
Constituents of the atmosphere.
995
On the motion of air.
996,
997,
998,
999
The globe an organism.
1000
. . .