A drawing of the last stage of a deluge or a deluge at sea: curling jets of rain descending from the clouds strike into the water, which curls up to meet them and foams and bubbles all round in a whirlpool. Melzi's number 1[46].

During the last years of his life Leonardo repeatedly treated the subject of a cataclysmic storm overwhelming a landscape, in both his drawings (RCIN 912376 - 912386) and his writings. This obsession with death and destruction can be seen as the deeply personal expression of an artist nearing his end – an artist who had seen some of his greatest creations unfinished or destroyed before his eyes, and who had a profound sense of the impermanence of all things, even of the earth itself.

Here all solid matter has been pulverised and swept away, and the scene is dominated by plumes of wind and water. But far from being chaotic, it is drawn with the eye of a scientist, fascinated by the forms and optical qualities of clouds, rain, floodwater, debris and dust.