On April 15th, 1452, a young peasant girl called Caterina gave birth to a son in the small town of Vinci not too far from Florence. His father, Ser Piero da Vinci, was a lawyer, and the little boy was Leonardo. He was to achieve fame in his lifetime as a painter, sculptor and architect, but it was only long after his death that it was discovered he was a gifted scientist. His anatomical drawings remain unsurpassed in detail, and he had worked out in essence the laws of physics that Newton and Galileo were to formulate years afterwards to great acclaim.
Leonardo's scientific talents were unknown because of a strange quirk of character: he was very secretive. Either from neurotic disinclination or from sober caution, da Vinci did not publish any of his scientific work, but kept it hidden in coded notebooks. They were closely packed with drawings and queries, explanations and experiments, all written in "mirror-image" handwriting from right to left.
Many of Leonardo's ideas concerned matters meteorological. On lunar coronae, for example, he says: "I find that those circles which at night seem to surround the moon, varying in circumference and in their degrees of redness, are caused by the different degrees of thickness of the vapours which are situated at different altitudes between the moon and our eyes. Where there appears greater redness there is a greater quantity of vapours."
And on thunderstorms he writes: "Immediately upon its creation, the lightning becomes visible to the eye, while the thunder requires time to travel after the manner of a wave, and makes the loudest noise when it meets with most resistance."
And he was also, in a general way, aware of a phenomenon known nowadays to meteorologists as a microburst, a spreading out in all directions at ground level of a strong descending current of air from within a thundercloud, often resulting in quite violent squalls: "The winds, descending from above to below at various angles, and, striking earth or water, set up lateral motions along various lines."
He also deduced the concept of air masses, a cornerstone of meteorology today: "Every wind," he wrote, "is by its nature cold and dry, but it takes to itself as many different attributes as are those of the places through which it passes; it leaves behind it, in passing, dampness and cold to the dry and hot places, and takes from these hot places their dryness and heat."
We might quarrel with the detail of some of these assessments, but Leonardo was close to the mark for someone who lived 500 years ago.