283
A Dynamic Role for Water in Agriculture
FIGURE 25.3 Spiral vortex in free water, viewed from above. (Photo credit: Simon Charter.)
FIGURE 25.4 Ring vortex, smoke in air. (Photo credit: stock image from pinterest.com.)
Leonardo da Vinci, often seen as a forerunner of modern natural scientists, appears to have been
aware of both these gestures. He made a close study of fow in water and is known to have used
sawdust as a marker to observe the streaming of the liquid. He illustrated both of these gestures in
a drawing (see Figure 25.6). The rings rising in the centre he called welling, and the spiral vortices
around them he called eddying.
Da Vinci did not draw the way the surface looks, but rather his pen followed the paths of movement, and in doing, so he drew out the curved path of the water to fnd the gestures that the fow
is making. For him, the drawing may have been a research methodology; he was looking for the
lawfulness in nature as an aspect of the divinity (Kemp, referring to Leonardo’s Codex Madrid II,
1989: 13).