‘Now,’ Toscanelli went on, adjusting the violet velvet cap on his head, ‘it may be that in some remote future men, yes, I say men, will take to the air, but this will never happen because of any spells but by their learning certain mathematical laws which are still unknown to us. It is only those who are blind to the truth who can see magic nature,’ added Toscanelli and returned the little bird to the shelf.
As he sat down again, he saw the light in Leonardo’s eyes.
‘Why, what’s the matter with you? Did I shock you by saying that men will fly one day?’
Leonardo answered, his voice hardly ore than a whisper:
‘Messere, ever since I was small, I believed in it. No, it seems more than a belief now. Men shall be free of air some day.’
Toscanelli’s smile was like a benediction.
 Almedingen, Martha, Edith, 1963: The Young Leonardo da Vinci; Illustrated by Azpelicueta; London: Max Parrish: 81