by GEOFFREY WEBB
Leonardo's drawings of floods and storms develop far beyond the theme of traditional apocalypse. 'The destruction has only happened because the creative intelligence has thought up something better yet, and is impatient to start some new creation. But the new creation - so Leonardo implies - will use the same vocabulary of forms, these spirals and curves and circles, that he has observed a thousand times already, whether in wind or water, or clouds or grasses, or a woman's hair '