t boring was very useful, but only as a process. When
employed as a mechanical device to represent the hair of the head, we
get the Roman Empress disguised as a sponge or a honeycomb. These
tricks reveal much more than pure technicalities of art.
Gainsborough's habit of using paint brushes four or five feet long
throws a flood of light upon theory and practice alike. There is,
however, another work, possibly by Donatello himself, which gives no
insight into anything but technical methods, but which is none the
less important. This is the large Madonna and Child surrounded by
angels, belonging to Signor Bardini of Florence. It is unhappily a
complete wreck, five heads, including the Child's, having been broken
away. It is a relief in stucco, modelled, not cast, and is closely
allied with a group of Madonnas to which reference is made
hereafter.[61] We can see precisely how this relief was made. The
stucco adheres to a strong canvas, which in its turn is nailed on to a
wooden panel. The background, also much injured, is decorated with
mosaic and geometrical patterns of glass, now dim and opaque with age.
The relief must have been of signal merit. Complete it would have
rivalled the polychrome Madonna of the Louvre: as a fragment it is
quite sufficient to prove that the Piot Madonna, in the same museum,
is not authentic. One more trick of the sculptor remains to be
noticed. Vasari and Bocchi say that Donatello, recognising the value
of his work, grouped his figures so that the limbs and drapery should
offer few protruding angles, in order to minimise the danger of
fracture. It was his insurance against the fragility of the stone:
when working in bronze such precautions would be less necessary. It is
quite true that in the larger figures there is a marked restraint in
this respect, while in his bas-reliefs, where the danger was less, the
tendency to raise the arms above the head is often exaggerated. But
too much stress should not be laid upon this explanation: it is hard
to believe that Donatello would have let so crucial a matter be
governed by such a consideration. Speaking generally, Donatello was
neither more nor less restrictive than his Florentine contemporaries,
and it was only at a later period that the isolated statue received
perfect freedom, such as that in the Cellini Perseus, or the Mercury
by Gian Bologna, or Bernini's work in marble.

[Footnote 58: In the Berlin Gallery.]

[Footnote 59: Berlin Museum.]