But it was out on the hillside that he spent his happiest hours. He loved every crawling, creeping, or flying thing, however ugly. Curious beasts which might have frightened another child were to him charming and interesting. There as he listened to the carolling of the birds and bent his head to catch the murmured song of the mountain-streams, the love of music began to steal into his heart.

He did not rest then until he managed to get a lute and learned how to play upon it. And when he had mastered the notes and learned the rules of music, he began to play airs which no one had ever heard before, and to sing such strange sweet songs that the golden notes flowed out as fresh and clear as the song of a lark in the early morning of spring.

`The child is a changeling,' said some, as they saw Leonardo tenderly lift a crushed lizard in his hand, or watched him play with a spotted snake or great hairy spider.

`A changeling perhaps,' said others, `but one that hath the voice of an angel.' For every one stopped to listen when the boy's voice was heard singing through the streets of the little town.

He was a puzzle to every one, and yet a delight to all, even when they understood him least.

So time went on, and when Leonardo was thirteen his father took him away to Florence that he might begin to be trained for some special work. But what work? Ah! that was the rub. The boy could do so many things well that it was difficult to fix on one.

At that time there was living in Florence an old man who knew a great deal about the stars, and who made wonderful calculations about them. He was a famous astronomer, but he cared not at all for honour or fame, but lived a simple quiet life by himself and would not mix with the gay world.

Few visitors ever came to see him, for it was known that he would receive no one, and so it was a great surprise to old Toscanelli when one night a gentle knock sounded at his door, and a boy walked quietly in and stood before him.

Hastily the old man looked up, and his first thought was to ask the child how he dared enter without leave, and then ask him to be gone, but as he looked at the fair face he felt the charm of the curious smile, and the light in the blue eyes, and instead he laid his hand upon the boy's golden head and said: `What dost thou seek, my son?'

`I would learn all that thou canst teach me,' said Leonardo, for it was he.

The old man smiled.

`Behold the boundless self-confidence of youth!' he said.

But as they talked together, and the boy asked his many eager questions, a great wonder awoke in the astronomer's mind, and his eyes shone with interest. This child-mind held depths of understanding such as he had never met with among his learned friends. Day after day the old man and the boy bent eagerly together over their problems, and when night fell Toscanelli would take the child up with him to his lonely tower above Florence, and teach him to know the stars and to understand many things.

`This is all very well,' said Ser Piero, `but the boy must do more than mere star-gazing. He must earn a living for himself, and methinks we might make a painter of him.'

That very day, therefore, he gathered together some of Leonardo's drawings which lay carelessly scattered about, and took them to the studio of Verocchio the painter, who lived close by the Ponte Vecchio.

`Dost thou think thou canst make aught of the boy?' he asked, spreading out the drawings before Verocchio.

The painter's quick eyes examined the work with deep interest.

`Send him to me at once,' he said. `This is indeed marvellous talent.'

So Leonardo entered the studio as a pupil, and learned all that could be taught him with the same quickness with which he learned anything that he cared to know.

Every one who saw his work declared that he would be the wonder of the age, but Verocchio shook his head.

`He is too wonderful,' he said. `He aims at too great perfection. He wants to know everything and do everything, and life is too short for that. He finishes nothing, because he is ever starting to do something else.'

Verocchio's words were true; the boy seldom worked long at one thing. His hands were never idle, and often, instead of painting, he would carve out tiny windmills and curious toys which worked with pulleys and ropes, or made exquisite little clay models of horses and all the other animals that he loved. But he never forgot the longing that had filled his heart when he was a child--the desire to learn the secret of flying.

For days he would sit idle and think of nothing but soaring wings, then he would rouse himself and begin to make some strange machine which he thought might hold the secret that he sought.

`A waste of time,' growled Verocchio. `See here, thou wouldst be better employed if thou shouldst set to work and help me finish this picture of the Baptism for the good monks of Vallambrosa. Let me see how thou canst paint in the kneeling figure of the angel at the side.'

For a while the boy stood motionless before the picture as if he was looking at something far away. Then he seized the brushes with his left hand and began to paint with quick certain sweep. He never stopped to think, but worked as if the angel were already there, and he were but brushing away the veil that hid it from the light.

Then, when it was done, the master came and looked silently on. For a moment a quick stab of jealousy ran through his heart. Year after year had he worked and striven to reach his ideal. Long days of toil and weary nights had he spent, winning each step upwards by sheer hard work. And here was this boy without an effort able to rise far above him. All the knowledge which the master had groped after, had been grasped at once by the wonderful mind of the pupil. But the envious feeling passed quickly away, and Verocchio laid his hand upon Leonardo's shoulder.