Design notes for an earth-moving excavation machine
A wheel, box and jib that lift dug earth onto an embankment by one man
Two long crossed-out passages, worked with the page turned on its side, argue for the merits of a machine that digs and carries earth. Leonardo praises how the soil goes by itself into the box, how his wheel always turns one way and is moved by a single man, and how the instrument throws the heaped earth up two levels. A second block compares his device against ordinary labour and against a rival machine (the Pesaro one): barrow-men bring 150 pounds of soil onto the embankment with great effort, while his carries 400 without effort, so that two of his men move a far greater weight in less time. A figure at upper right is labelled all the men.
On this page
A wheel driven by one man, always turning one way
My soil goes by itself into the box, my wheel always turns, my wheel always turns in one direction, my instrument is moved by one man, my instrument throws the heaped earth up two levels. Leonardo counts the timber a lasting cost because it does not spoil.
Excavated earth leaps by itself into the box
The greatest merit claimed is that the soil, of its own accord, leaps from every part of the ditch onto the instrument that carries it out. The full box empties itself and returns empty as the other goes full, without loss of time.
Carrying 400 lb without effort against 150 by barrow
Those who carry barrows bring 150 pounds of soil onto the embankment with great effort; his machine, without effort, brings 400. Therefore his two men carry a weight 250 greater than the first, and in a shorter time.
