Michelangelo’s lifetime and with his approval.  There is good reason to believe that this may have been the case:  first, because the tambour, which he executed, differs from the model in the arching of its windows; secondly, because Fontana and other early writers on the cupola insist strongly on the fact that Michelangelo’s own plans were strictly followed, although they never allude to the third or innermost vault.  It is almost incredible that if Della Porta departed in so vital a point from Michelangelo’s design, no notice should have been taken of the fact.  On the other hand, the tradition that Della Porta improved the curve of the cupola by making the spring upward from the attic more abrupt, is due probably to the discrepancy between the internal aspects of the model and the dome itself.  The actual truth is that the cupola in its curve and its dimensions corresponds accurately to the proportions of the double outer vaulting of the model.

Taking, then, Vasari’s statement in conjunction with the silence of Fontana, Poleni, and other early writers, and duly observing the care with which the proportions of the dome have been preserved, I think we may safely conclude that Michelangelo himself abandoned the third or semi-spherical vault, and that the cupola, as it exists, ought to be ascribed entirely to his conception.  It is, in fact, the only portion of the basilica which remains as he designed it.

CHAPTER XIV

I

There is great difficulty in dealing chronologically with the last twenty years of Michelangelo’s life.  This is due in some measure to the multiplicity of his engagements, but more to the tardy rate at which his work, now almost wholly architectural, advanced.  I therefore judged it best to carry the history of his doings at S. Peter’s down to the latest date; and I shall take the same course now with regard to the lesser schemes which occupied his mind between 1545 and 1564, reserving for the last the treatment of his private life during this period.

A society of gentlemen and artists, to which Buonarroti belonged, conceived the plan of erecting buildings of suitable size and grandeur on the Campidoglio.  This hill had always been dear to the Romans, as the central point of urban life since the foundation of their city, through the days of the Republic and the Empire, down to the latest Middle Ages.  But it was distinguished only by its ancient name and fame.  No splendid edifices and majestic squares reminded the spectator that here once stood the shrine of Jupiter Capitolinus, to which conquering generals rode in triumph with the spoils and captives of the habitable world behind their laurelled chariots.  Paul III. approved of the design, and Michelangelo, who had received the citizenship of Rome on March 20, 1546, undertook to provide a scheme for its accomplishment.  We are justified in believing that the disposition of