Pump drives, a self-turning water-and-lead wheel, and a stream-driven screw
Figures 4-7 with a lettered perpetual-motion instrument (a-g)
The page gathers several water machines: three toothed wheels driving three piston pumps (Fig. 4); wheels and Archimedean screws that move a rod, and a pivoted semicircle that lifts two containers and pours out water (Fig. 5); a truncated-cone wheel turned by a flowing stream that in turn drives a double Archimedean screw (Fig. 6); and a four-wheel system working a pair of piston pumps (Fig. 7). At the centre a rotating instrument is lettered a-g, with a long note describing chambers of water, air and lead that overbalance and keep the device 'always in motion' — one of Leonardo's perpetual-motion schemes. Dense mirror-script fills the lower-left margin.
On this page
Self-turning instrument of water, air and lead (a-g)
Water falling from mouth g is pressed out of tank f by the lead d; when that tank empties, water rises into tank a through an inward-opening valve. With the lower part lightened and the upper part weighted, the device turns over and lead c presses on tank a, so that it 'is always in motion'.
Figure 6: stream-driven cone wheel turning a double screw
A truncated-cone wheel set in a flowing stream is turned by the current and in turn drives a double Archimedean screw. The arrangement uses running water both as power source and as the medium to be raised.
Figure 4: three toothed wheels driving three piston pumps
A train of three toothed wheels drives three piston pumps in sequence. It is one of several pump-driving gear arrangements studied across these folios.