[Illustration: _Alinari_

EFFIGY OF POPE JOHN XXIII.

BAPTISTERY, FLORENCE]


[Sidenote: Michelozzo and the Coscia Tomb.]

For ten years Donatello was associated with Michelozzo,[90] who began
as assistant and finally entered into a partnership which lasted until
1433. The whole subject is obscure, and until we have a critical
biography of Michelozzo his relation with various men and monuments of
the fifteenth century must remain problematical. Michelozzo has not
hitherto received his due meed of appreciation. As a sculptor and
architect he frequently held a subordinate position, and it has
been assumed that he therefore lacked independence and originality.
But the man who was Court architect of the Medici, and director of the
Cathedral building staff, was no mere hack; while his sculpture at
Milan, Naples, and Montepulciano show that his plastic abilities were
far from mean. He was a great man with interludes of smallness. When
Donatello required technical help in casting, Michelozzo was called
in. Though Donatello had worked for Ghiberti on the bronze gates, he
was never quite at home in the science of casting. Gauricus says he
always employed professional help--"_nunquam fudit ipse, campanariorum
usus opera semper_."[91] Caldieri cast for him at Padua. Michelozzo
also helped Luca della Robbia in casting the Sacristy gates which
Donatello should have made; the commissions which Donatello threw over
were those for work in bronze. The partnership extended over some of