“The messenger,” continues Vasari, “when on his way to visit Giotto, and to inquire what other good masters there were in Florence, spoke first with many artists in Siena⁠—then, having received designs from them, he proceeded to Florence, and repaired one morning to the workshop where Giotto was occupied with his labors. He declared the purpose of the Pope, and the manner in which that Pontiff desired to avail himself of his assistance; and, finally, requested to have a drawing, that he might send it to his Holiness, Giotto, who was very courteous, took a sheet of paper and a pencil dipped in a red color, then, resting his elbow on his side, to form a sort of compass, with one turn of the hand he drew a circle, so perfect and exact that it was a marvel to behold.