‘Vasari also relates that when Pope Benedict XI sent a messenger to Giotto, asking him to send a drawing to demonstrate his skill, Giotto drew a red circle so perfect that it seemed as though it was drawn using a pair of compasses and instructed the messenger to send it to the Pope. The messenger departed ill-pleased, believing that he had been made a fool of. The messenger brought other artists' drawings back to the Pope in addition to Giotto's. When the messenger related how he had made the circle without moving his arm and without the aid of compasses the Pope and his courtiers were amazed at how Giotto's skill greatly surpassed all of his contemporaries.’
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