Drilling machine

"If you wanted easily dig a hole underground, be provided with the instrument depicted above; in order to dig the hole, you shall then turn the screw with the lever, and the screw will drive itself into the ground, and, as a female it will meet the earth"

This machine makes drilling and digging possible. It worked in the following way: the drill was driven into the ground by rotating the upper bar, while, by rotating the second bar, the drill was heaved back up without turning and it lifted out of the ground all the earth which had collected on it. The double-movement drilling machine was conceived by Leonardo before his arrival in Milan.
Manuscript B, sheet 65 recto