A study of a cascade of falling water issuing from a hole and falling on the surface of a pool, with accompanying notes; two studies of waveforms and more notes. Originally joined to RCIN 912664. The drawing shown in RCIN 912660v s the most masterly of Leonardo’s drawings of the movement of water. The principal study shows the eddies and bubbles resulting from water falling from a sluice into a pool; the same topic is studied on RCIN 912661 and 912662 (the upper studies inverted), with each drawing recording a different pattern. They exemplify Leonardo’s uncanny ability to fix a momentary impression in his mind and capture it on paper with absolute conviction, as if the endlessly changing scene had been frozen before him. The movement of water haunts Leonardo’s work in many fields. In his landscapes it is a symbol of natural processes over unconscionable timespans (eg. RCIN 912395, 912387); in his civil engineering projects it is a powerful but tractable adversary (RCIN 912278, 912279); and in his scientific studies it is a pure element, responding perfectly to external forces in a manner that can be observed and analysed. Leonardo’s work on water reached a peak during his years in Milan between 1506 and 1513, and several notebooks from that time, particularly the Codex Leicester, are rich with observations on the movement of water. Text adapted from Leonardo da Vinci: A life in drawing, London, 2018