erical shell
was abandoned during 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. N