Being in tempera it cannot be cleaned, and a dulness is overlaying it; but nothing can deprive the figure of Spring of her joy and movement, a floating type of conquering beauty and youth.

The most wonderful thing about this wonderful picture is that it should have been painted when it was: that, suddenly, out of a solid phalanx of Madonnas should have stepped these radiant creatures of the joyous earth, earthy and joyful.

And not only that they should have so surprisingly and suddenly emerged, but that after all these years this figure of Spring should still be the finest of her kind.

That is the miracle! Luca Signorelli's flowers at the Uffizi remain the best, but Botticelli's are very thoughtful and before the grass turned black they must have been very lovely; the exquisite drawing of the irises in the right-hand corner can still be traced, although the colour has gone.

The effect now is rather like a Chinese painting.