His theory of vortices--assuming a uniform material regulated by physical laws--as the beginning of the visible universe, though it was but a provisional hypothesis, had ended the whole old theory of the heavens with the vaulted firmament and the direction of the planetary movements by angels, which even Kepler had allowed.

The scientific warriors had stirred new life in him, and he was working over and summing up in his mighty mind all the researches of his time.

The result would have made an epoch in history.

His aim was to combine all knowledge and thought into a Treatise on the World, and in view of this he gave eleven years to the study of anatomy alone.

But the fate of Galileo robbed him of all hope, of all courage; the battle seemed lost; he gave up his great plan forever.( 72) (72) For Descartes's discouragement, see Humboldt, Cosmos, London, 1851, vol iii, p.