Pope Julius was always very desirous to see any undertakings that he was having carried out, and therefore became more eager than ever to see this one, which was hidden from him. And so one day he resolved to go to see it, but was not admitted, for Michelagnolo would never have consented to show it to him; out of which affair arose the quarrel that has been described, when he had to depart from Rome because he would not show his work to the Pope. Now, when a third of the work was finished (as I ascertained from him in order to clear up all doubts), it began to throw out certain spots of mould, one winter that the north wind was blowing. The reason of this was that the Roman lime, which is made of travertine and white in colour, does not dry very readily, and, when mixed with pozzolana, which is of a tawny colour, makes a dark mixture which, when soft, is very watery; and when the wall has been well soaked, it often breaks out into an efflorescence in the drying; and thus this salt efflorescence of moisture came out in many places, but in time the air consumed it. Michelagnolo was in despair over this, and was unwilling to continue the work, asking the Pope to excuse him, since he was not succeeding; but his Holiness sent Giuliano da San Gallo to see him, and he, having told him whence the defect arose and taught him how to remove the spots of mould, encouraged him to persevere. Now, when he had finished half of it, the Pope, who had subsequently gone to see it several times (mounting certain ladders with the assistance of Michelagnolo), insisted that it should be thrown open, for he was hasty and impatient by nature, and could not wait for it to be completely finished and to receive, as the saying is, the final touch. No sooner was it thrown open than all Rome was drawn to see it, and the Pope was the first, not having the patience to wait until the dust caused by the dismantling of the scaffolding had settled. Thereupon Raffaello da Urbino, who was very excellent in imitation, after seeing it straightway changed his manner, and without losing any time, in order to display his ability, painted the Prophets and Sibyls in the work of the Pace; and at the same time Bramante sought to have the other half of the chapel entrusted by the Pope to Raffaello. Which hearing, Michelagnolo complained of Bramante, and revealed to the Pope without any reserve many faults both in his life and in his architectural works; of which last, in the building of S. Pietro, as was seen afterwards, Michelagnolo became the corrector. But the Pope, recognizing more clearly every day the ability of Michelagnolo, desired that he should continue the work, judging, after he had seen it uncovered, that he could make the second half considerably better; and so in twenty months he carried that work to perfect completion by himself alone, without the assistance even of anyone to grind his colours. Michelagnolo complained at times that on account of the haste