As Perugino noted this, he grew angry and determined to punish the prior's meanness. The next time therefore that there was a blue sky to be painted, he put at his side a large bowl of fresh water, and then called on the prior to put out a small quantity of the blue colour in a little vase. Each time he dipped his brush into the vase, Perugino washed it out with a swirl in the bowl at his side, so that most of the colour was left in the water, and very little was put on to the picture.
'I pray thee fill the vase again with blue,' he said carelessly when the colour was all gone. The prior groaned aloud, and turned grudgingly to his little bag.
'Oh what a quantity of blue is swallowed up by this plaster!' he said, as he gazed at the white wall, which scarcely showed a trace of the precious colour.
'Yes,' said Perugino cheerfully, 'thou canst see thyself how it goes.'
Then afterwards, when the prior had sadly gone off with his little empty bag, Perugino carefully poured the water from the bowl and gathered together the grains of colour which had sunk to the bottom.
'Here is something that belongs to thee,' he said sternly to the astonished prior. 'I would have thee learn to trust honest men and not treat them as thieves. For with all thy suspicious care, it was easy to rob thee if I had had a mind.'
During all these years in which Perugino had worked so diligently, the art of painting had been growing rapidly. Many of the new artists shook off the old rules and ideas, and began to paint in quite a new way. There was one man especially, called Michelangelo, whose story you will hear later on, who arose like a giant, and with his new way and greater knowledge swept everything before him.
Perugino was jealous of all these new ideas, and clung more closely than ever to his old ideals, his quiet, dignified saints, and spacious landscapes. He talked openly of his dislike of the new style, and once he had a serious quarrel with the great Michelangelo.
There was a gathering of painters in Perugino's studio that day. Filippino Lippi, Botticelli, Ghirlandaio, and Leonardo were there, and in the background the pupil Raphael was listening to the talk.
'What dost thou think of this new style of painting?' asked Botticelli. 'To me it seems but strange and unpleasing. Music and motion are delightful, but this violent twisting of limbs to show the muscles offends my taste.'