1077

The Appenins.

If the river m n, an affluent of the river Loire, were turned with its muddy waters, into the river of Romorantin, this would fatten the land which it would water and would render the country fertile to supply food to the inhabitants, and would make navigable canals for mercantile purposes.

The way in which the river in its flow should scour its own channel.

By the ninth of the third; the more rapid it is, the more it wears away its channel; and, by the converse proposition, the slower the water the more it deposits that which renders it turbid.

And let the sluice be movable like the one I arranged in Friuli [Footnote 19: This passage reveals to us the fact that Leonardo had visited the country of Friuli and that he had stayed there for some time. Nothing whatever was known of this previously.], where when one sluice was opened the water which passed through it dug out the bottom. Therefore when the rivers are flooded, the sluices of the mills ought to be opened in order that the whole course of the river may pass through falls to each mill; there should be many in order to give a greater impetus, and so all the river will be scoured. And below the site of each of the two mills there may be one of the said sluice falls; one of them may be placed below each mill.

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

Notebooks of Leonoardo da Vinci
XVII: Topographical Notes.
. . .
The Alps.
1057,
1058,
1059,
1060,
1061,
1062
The Appenins.
1063,
1064,
1065,
1066,
1067,
1068,
1069,
1070,
1071,
1072,
1073,
1074,
1075,
1076,
1077,
1078,
1079,
1080,
1081,
1082
The straits of Gibraltar.
1083,
1084,
1085
Tunis.
1086
Libya.
1087
Majorca.
1088
The Tyrrhene Sea.
1089
The Levantine Sea.
1090
The Red Sea..
1091,
1092
The Nile.
1093,
1094,
1095,
1096,
1097
. . .