These works brought them no less fame and renown than comfort in life. But Maestro Claudio, being very intemperate in eating and drinking, according to the custom of his race, which is a deadly thing in the air of Rome, fell sick of so violent a fever, that in six days he passed to the other life. Whereupon Guglielmo, left alone, and almost like one lost without his companion, painted by himself a window, likewise of glass, in S. Maria de Anima, the church of the Germans in Rome; which was the reason that Cardinal Silvio of Cortona made him an offer, and made a contract with him that he should execute some windows and other works in his native city of Cortona. Wherefore the Cardinal took him in his company to take up his abode in Cortona; and the first work that he executed was the facade of the Cardinal's house on the side towards the Piazza, which he painted in chiaroscuro, depicting therein Croton and the other original founders of that city. Thereupon the Cardinal, who saw that Guglielmo was no less upright as a man than excellent as a master of that art, caused him to execute, for the Pieve of Cortona, the window of the principal chapel, in which he made the Nativity of Christ and the Magi adoring Him. Guglielmo was a man of fine spirit and intelligence, and of very great mastery in handling glass, and particularly in so distributing the colours that the brightest should come in the foremost figures, those in the other figures being darker in proportion as they receded; in which point he was a rare and truly excellent master. Moreover, he showed very good judgment in the painting of his figures; whereby he executed them with such unity, that they fell back into the distance little by little, in such a way that they did not cling either to the buildings or to the landscapes, and had the appearance of being painted on panel, or rather in relief. He showed invention and variety in the composition of scenes, making them rich and well grouped; and he rendered easy the process of making such pictures as are put together out of pieces of glass, which was held to be very difficult, as indeed it is for one who has not his skill and dexterity. He designed the pictures for his windows with such good method and order, that the mountings of lead and iron, which cross them in certain places, were so well fitted into the joinings of the figures and the folds of the draperies, that they cannot be seen--nay, they gave the whole such grace, that the brush could not have done more--and thus he was able to make a virtue of necessity.