of a
group is that there should be something to unite the figures. We find
this in the Abraham, but the four martyrs by Nanni di Banco are
standing close together as if by chance, and cannot properly be called
a group in anything but juxtaposition of figures. Il Rosso helped to
make Abraham. The commission was given jointly to the two sculptors in
March 1421, and the statue was finished, with unusual expedition, by
November of the same year. The hand of Rosso cannot be easily detected
except in the drapery, which differs a good deal from Donatello's. The
latter must have been chiefly responsible for the grouping and wholly
so for the fine head of Abraham.

* * * * *

[Sidenote: Drapery and Hands.]

Rosso's drapery was apt to be treated in rather a small way with a
number of little folds. Donatello, on the other hand, often tended to
the opposite extreme, and in the Campanile figures we see the clothes
hanging about the prophets in such ample lines that the Zuccone and
Jeremiah are overweighted with togas which look like heavy blankets.
Habbakuk and the Baptist are much more skilfully draped, deference
being shown to the anatomy. "To make drapery merely natural," said Sir
Joshua Reynolds, "is a mechanical operation to which neither genius
nor taste are required: whereas it requires the nicest judgment to
dispose the drapery so that the folds have an easy communication, and
gracefully follow each other with such natural negligence as to look
like the effect of chance, and at the same time show the figure under
it to the utmost advantage."[27] The sculptors of the fifteenth
century did not find it so easy to make drapery look purely natural,
and we are often confronted by cases where they failed in this
respect. It arose partly from a belief that drapery was nothing more
than an accessory, partly also from their ignorance of what was so
fully realised by the Greeks, that there can be very little grace in a
draped figure unless there are the elements of beauty below. Another
comment suggested by Donatello's early work in marble is that he was
not quite certain how to model or dispose the hands. They are often
unduly big; Michael Angelo started with the same mistake: witness his
David and the Madonna on the Stairs. It was a mistake soon rectified
in either case. But till late in life Donatello never quite succeeded
in giving nerve or occupation to his hands. St. Mark, St. Peter, and
St. Joh