od of his life he aimed at
something broad and heroic in style. He sought to attain grandeur by
greatness in the masses and by economy of the constituent parts. His
method of securing amplitude was exactly opposite to that of Sangallo,
who relied upon the multiplication rather than the simplification of
details. A kind of organic unity was what Michelangelo desired. For
this reason, he employed in the construction of S. Peter's those
stupendous orders which out-soar the columns of Baalbec, and those
grandiose curves which make the cupola majestic. A letter written to
the Cardinal Ridolfo Pio of Carpi contains this explanation of his
principles. The last two sentences are highly significant:--

"Most Reverend Monsignor,--If a plan has divers parts, those which are
of one type in respect to quality and quantity have to be decorated in
the same way and the same fashion. The like is true of their
counterparts. But when the plan changes form entirely, it is not only
allowable, but necessary, to change the decorative appurtenances, as
also with their counterparts. The intermediate parts are always free,
left to their own bent. The nose, which stands in the middle of the
forehead, is not bound to correspond with either of the eyes; but one
hand must balance the other, and one eye be like its fellow. Therefore
it may be assumed as certain that the members of an architectural
structure follow the laws exemplified in the human body. He who has
not been or is not a good master of the nude, and especially of
anatomy, cannot understand the principles of architecture."

It followed that Michelangelo's first object, when he became Papal
architect-in-chief, was to introduce order into the anarchy of
previous plans, and to return, so far as this was now possible, to
Bramante's simpler scheme. He adopted the Greek cross, and substituted
a stately portico for the long vestibule invented by Sangallo. It was
not, however, in his nature, nor did the changed taste of the times
permit him to reproduce Bramante's manner. So far as S. Peter's bears
the mark of Michelangelo at all, it represents his own peculiar
genius. "The Pope," says Vasari, "approved his model, which reduced
the cathedral to smaller dimensions, but also to a more essential
greatness. He discovered that four principal piers, erected by
Bramante and left standing by Antonio da Sangallo, which had to bear
the weight of the tribune, were feeble. These he fortified in part,
cons