When you put together the science of the motions of water, remember to include under each proposition its application and use, in order that this science may not be useless.—
[Footnote: A comparatively small portion of Leonardo’s notes on water-power was published at Bologna in 1828, under the title: “Del moto e misura dell’Acqua, di L. da Vinci”.]
Taken from The Notebooks of Leonardo da Vinci edited by Jean Paul Richter, 1880.