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St. 17. “O!”: Boniface VIII. (not Benedict IX., as Vasari has it), wishing to employ Giotto, sent a courtier to obtain some proof of his skill. The latter requesting a drawing to send to his Holiness, Giotto took a sheet of paper and a pencil dipped in red color; then resting his elbow on his side, to form a compass, with one turn of his hand he drew a circle so perfect and exact, that it was a marvel to behold. This done, he turned to the courtier, saying, “Here is your drawing.” The courtier seems to have thought that Giotto was fooling him; but the pope was easily convinced, by the roundness of the O, of the greatness of Giotto’s skill. This incident gave rise to the proverb, “Tu sei piu tondo che l’ O di Giotto”, the point of which lies in the word ‘tondo’, signifying slowness of intellect, as well as a circle. --Adapted from Vasari and Heaton.