Again if the lowest part of the bank which lies across the current
of the waters is made in deep and wide steps, after the manner of
stairs, the waters which, in their course usually fall
perpendicularly from the top of such a place to the bottom, and wear
away the foundations of this bank can no longer descend with a blow
of too great a force; and I find the example of this in the stairs
down which the water falls in the fields at Sforzesca at Vigevano
over which the running water falls for a height of 50 braccia.