rected, shadows would appear matte and therefore cool and come fo rward
rather than giving the intended effects of depth (13).
Armenini is also aware of this problem. In his De' veri precetti della pittura
(1587), speaking of shadows and contours he says: "They never remain suf
ficiently finished ... but will always sink in, or the darks become cruder so
that it is necessary to come back to them many times in order to make them
fresh, blended, soft, and pleasing" (14).
Absorbency of the grounds
The problem of overabsorbent grounds, which is identified by Baldinucci as
the cause fo r localized applications of varnish, is also a problem that reoccurs
in Symonds's notes and obviously concerned Canini and presumably the oth
er artists in this circle.
Almost all of the samples taken from paintings produced in central Italy circa
1600-1800 showed the presence of chalk in varying but significant propor
tions. Sometimes chalk was fo und as a single ground layer, as in the case of
Domenichino's Vision of St. Jerome of 1603 (National Gallery, London); in
Annibale Carracci's Boy Drinking (Christ Church Gallery, Oxford) which
probably dates from the end of the sixteenth century; and in the much later
Cavallino, Christ Driving the Traders from the Temple (National Gallery, Lon
don).
This type of ground derives from Venetian painting and is fo und, fo r instance,
in Titian's Madonna and Child (ca. 1525), in which what appears to be the
dark ground is in fa ct the saturated color of the canvas. The refractive index
of chalk is so low that it is almost completely transparent when associated
with oil.
Not enough analyses have been carried out to ascertain whether the chalk
was applied in an aqueous or oil medium. More often the chalk is fo und
mixed with earth pigments and small inclusions of other pigments such as
charcoal black, or with driers such as lead white or an umber, as is the case
with Caravaggio's works in the National Gallery in London (15). In a thin
section taken from Poussin's Finding of Moses (National Gallery, London), one
can see that the absorbency of the ground was recognized and an isolating
oil layer applied. The sample was taken from a blanched area, in which both
the ground and the paint film were very lean. Interestingly enough, in other
areas containing lead white, the paint film was less lean and less absorbent.Symonds wrote, "It is good to give a mano [hand] of gesso first, and then oil
on top." Earth from which bricks are made is ground and used fo r the im
primatura, Symonds wrote, recording the recipe fo r the ground favored by
Canini: After sizing the canvas, he applied a mixture of "red earth, a little
white lead, a little charcoal black, and chalk" ( 16 ). Until now the latter seemed
always to have been interpreted as white clay, although brick clay seems per
fe ctly adequate. This mixture was applied to the canvas in an oil medium.
The absorbency of the ground seems to have been both fe ared (because of
the problem of sinking in) and desired (because it kept the colors fresh). As
Symonds wrote, "These cloths that have gesso in their imprimatura-the
gesso makes the colour keep fresher and does drink up the evil of the oil,
but they crack sooner, and that is the worse of the gesso" (17). The sinking
in of colors, Symonds's "prosciugare," seems to be linked in their minds to
the poor drying of the ground, either because the commercial primer left
out the lead white fo r economy's sake (18), which seems to reduce the po
rosity of the paint film, or because it had not dried sufficiently before the
painting was executed.
Then, as today, the poor drying qualities of earth pigments were recognized
but not fu lly understood. From analyses we know that when the pigment in
the oil film is an earth color, there is a surprisingly high percentage of scissionGlanville 15