PLASTER AND STUCCO
In the masonry of the pyramids, plaster is constantly used, both to
fill joints as a bedding, and to level up hollows in a face. The
plaster used is a mixture of ordinary lime and plaster of Paris, the
carbonate and sulphate of lime. How it was introduced into the joints
of the pyramid casing is a mystery. The blocks at the base weigh
sixteen tons, so that no free sliding to reduce the joint-filling could
be done; yet the vertical joint, five feet high and seven feet long,
is filled with a film of plaster only a fiftieth of an inch thick.
The joints of the masonry in the passages and chambers are all filled
with plaster, though so close as to be almost imperceptible. In the
core masonry a coarse plaster was poured between the stones and filled
into hollows. The flaws and defects in the faces of stones were freely
filled with plaster, which was coloured to match the stone. In rock
tombs plaster was used to fill up cracks and hollows; and it often
remains in perfect condition while the rock around has decayed.
Plaster was also used on the brick walls, which were faced with a
hard coat about a tenth to a sixteenth of an inch thick, upon which
paintings were executed. By the XVIIIth dynasty this became a mere
whitewash over the mud-facing of the wall. In the roughly-hewn rock
tombs of that age at Thebes, the jagged surfaces were smoothed by a
coat of plaster, often two or three inches thick in the hollows. A
strange use of stucco was for a thin coat over sculpture, as a basis
for colouring. Such a coat was even laid over statuary. In all ages
this hid to some extent the full detail of the sculptor’s work in
reliefs. In the XIIth dynasty the finest lines were hidden by it; and
on coming down to the Ptolemaic times the plasterer ignored all the
sculpture below, filling the figures with a smooth daub of plaster
on which the painter drew what he liked. It seems strange why the
sculptors should have continued to put fine work and detail on to a
surface where they were going to be at once ignored. It suggests a
rigid bureaucracy in which the sculpture had to be passed by one man,
and the painting by another, without any collaboration.
Stucco was used for independent modelling, as in Italy. It was laid on
a flat canvas base, stretched over wood, and the whole relief was in
the stucco. The chariot of Tahutmes IV is one of the main examples of
such work, of which a small portion is shown in fig. 132. The relief is
low and smooth, and full of detail; there is none of the sketchy rough
tooling, as seen in Roman stucco reliefs. Minute details of dress and
hair are all tooled in, and supply some of the best studies of Syrian
robes. The varying patterns on the shields of different branches of
Syrians, the feathering of the arrows, the shape of the daggers, and
the flowers of the papyrus and lotus of north and south, are all most
precisely rendered. It would be hard to find any point in which more
details could be introduced.
[Illustration: PLASTER
132. Stucco relief modelling (XVIIIth dynasty)
133, 134. Plaster castings for studies]
Plaster was also used for casting in moulds, and for making moulds.
The death mask of Akhenaten shows how such castings were produced in
the XVIIIth dynasty, from a single mould without any undercutting, to
serve the purpose of the sculptor as a model. Of later examples of
such castings we have here a lion’s head and a king’s head (figs. 133,
134). They were probably made to be supplied as school copies to the
workshops where the sculptors were trained. Plaster moulds are very
common at Memphis, and it is said they were even used for casting
bronze work. This is very doubtful, as plaster is reduced to powder at
260° C., while moulds for bronze casting must be heated to 1500° to
1800° C.; they are more probably for casting pewter. Plaster moulds
were also used for moulding pottery lamps. The oiling of plaster was
done on painted plaster statuettes, so as to make them waterproof. They
can still be scrubbed in water without disturbing the colour.
The most artistic use of plaster was for the modelled heads, which
were placed on mummy cases in Roman times. Though most such works were
rather crude, some are found which show real ability of portraiture. In
fig. 135 we have a sympathetic study of the face of a young man. The
lips are beautifully true, the modelling of the cheek is quite natural,
the nose and brow well formed; only the eyes have been left blank,
and marked afterwards with colour. The head, fig. 136, is evidently a
careful study, giving the cautious, cold expression of the man. Another
face (fig. 137) is subtle, and full of feeling: the faint smile on the
lips, the gracious contour of the cheek, the wavy hair, give a memory
in death of a real personality. The only jarring feature is the square
brow, copied from an unfortunate convention in Greek art. The eyes
are here again left blank; but they seem to have been intended to be
open, by the slight ridge of the raised lid. Was there a convention of
regarding the dead as incapable of seeing, though seen by memory? How
far these modelled heads were portraits is answered in a curious way by
fig. 138. The light outline there is that of the plaster modelling, the
dark outline within it is the skull from the interior of the coffin.
It will be seen how exactly they agree; there is a thin skin over the
forehead, then a fleshy part to the brow. Along the bridge of the nose
the model closely follows the bone; below the nose the angle of meeting
of the jaws exactly agrees, leaving a uniform thickness of lips;
and lastly, the fleshy fulness of the chin is seen projecting. This
agreement is one which the artist could never have expected to be thus
tested, and therefore gives us the more confidence in his skill.
[Illustration: PLASTER
135, 136, 137. Modelled heads
138. Modelled head and skull]