The Ten Books on Architecture
gypsum, by setting too quickly should keep the work from drying
uniformly. We must also beware of the ancients' scheme for vaultings;
for in their mouldings the soffits overhang very heavily, and are
dangerous.
4. Some mouldings are flat, others in relief. In rooms where there has
to be a fire or a good many lights, they should be flat, so that they
can be wiped off more easily. In summer apartments and in exedrae where
there is no smoke nor soot to hurt them, they should be made in relief.
It is always the case that stucco, in the pride of its dazzling white,
gathers smoke not only from its own house but also from others.
5. Having finished the mouldings, apply a very rough rendering coat to
the walls, and afterwards, when the rendering coat gets pretty dry,
spread upon it the layers of sand mortar, exactly adjusted in length to
rule and line, in height to the plummet, and at the angles to the
square. The stucco will thus present a faultless appearance for
paintings. When it gets pretty dry, spread on a second coat and then a
third. The better the foundation of sand mortar that is laid on, the
stronger and more durable in its solidity will be the stucco.
6. When not less than three coats of sand mortar, besides the rendering
coat, have been laid on, then, we must make the mixture for the layers
of powdered marble, the mortar being so tempered that when mixed it does
not stick to the trowel, but the iron comes out freely and clean from
the mortar trough. After this powdered marble has been spread on and
gets dry, lay on a medium second coat. When that has been applied and
well rubbed down, spread on a finer coat. The walls, being thus rendered
solid by three coats of sand mortar and as many of marble, will not
possibly be liable to cracks or to any other defect.
7. And further, such walls, owing to the solid foundation given by
thorough working with polishing instruments, and the smoothness of it,
due to the hard and dazzling white marble, will bring out in brilliant
splendour the colours which are laid on at the same time with the
polishing.
These colours, when they are carefully laid on stucco still wet, do not
fade but are permanent. This is because the lime, having had its
moisture burned out in the kiln, becomes porous and loses its strength,
and its dryness makes it take up anything that may come in contact with
it. On mixing with the seeds or elements that come from other
substances, it forms a solid mass with them and, no matter what the
constituent parts may then be, it must, obviously, on becoming dry,
possess the qualities which are peculiar to its own nature.
8. Hence, stucco that is properly made does not get rough as time goes
on, nor lose its colours when it is wiped off, unless they have been
laid on with little care and after it is dry. So, when the stucco on
walls is made as described above, it will have strength and brilliancy,
and an excellence that will last to a great age. But when only one coat
of sand mortar and one of fine marble have been spread on, its thin
layer is easily cracked from want of strength, and from its lack of
thickness it will not take on the brilliance, due to polishing, which it
ought to have.
9. Just as a silver mirror that is formed of a thin plate reflects
indistinctly and with a feeble light, while one that is substantially
made can take on a very high polish, and reflects a brilliant and
distinct image when one looks therein, so it is with stucco. When the
stuff of which it is formed is thin, it not only cracks but also soon
fades; when, however, it has a solid foundation of sand mortar and of
marble, thickly and compactly applied, it is not only brilliant after
being subjected to repeated polishings, but also reflects from its
surface a clear image of the beholder.
10. The Greek stucco-workers not only employ these methods to make their
works durable, but also construct a mortar trough, mix the lime and sand
in it, bring on a gang of men, and beat the stuff with wooden beetles,
and do not use it until it has been thus vigorously worked. Hence, some
cut slabs out of old walls and use them as panels, and the stucco of
such panels and "reflectors" has projecting bevelled edges all round it.
11. But if stucco has to be made on "wattle and daub," where there must
be cracks at the uprights and cross-sticks, because they must take in
moisture when they are daubed with the mud, and cause cracks in the
stucco when they dry and shrink, the following method will prevent this
from happening. After the whole wall has been smeared with the mud, nail
rows of reeds to it by means of "fly-nails," then spread on the mud a
second time, and, if the first rows have been nailed with the shafts
transverse, nail on a second set with the shafts vertical, and then, as
above described, spread on the sand mortar, the marble, and the whole
mass of stucco. Thus, the double series of reeds with their shafts
crossing on the walls will prevent any chipping or cracking from taking
place.
CHAPTER IV
ON STUCCO WORK IN DAMP PLACES, AND ON THE DECORATION OF DINING ROOMS
1. Having spoken of the method by which stucco work should be done in
dry situations, I shall next explain how the polished finish is to be
accomplished in places that are damp, in such a way that it can last
without defects. First, in apartments which are level with the ground,
apply a rendering coat of mortar, mixed with burnt brick instead of
sand, to a height of about three feet above the floor, and then lay on
the stucco so that those portions of it may not be injured by the
dampness. But if a wall is in a state of dampness all over, construct a
second thin wall a little way from it on the inside, at a distance
suited to circumstances, and in the space between these two walls run a
channel, at a lower level than that of the apartment, with vents to the
open air. Similarly, when the wall is brought up to the top, leave
airholes there. For if the moisture has no means of getting out by vents
at the bottom and at the top, it will not fail to spread all over the
new wall. This done, apply a rendering coat of mortar made with burnt
brick to this wall, spread on the layer of stucco, and polish it.
2. But if there is not room enough for the construction of a wall, make
channels with their vents extending to the open air. Then lay two-foot
tiles resting on the margin of the channel on one side, and on the other
side construct a foundation of pillars for them, made of eight-inch
bricks, on top of each of which the edges of two tiles may be supported,
each pillar being not more than a hand's breadth distant from the wall.
Then, above, set hooked tiles fastened to the wall from bottom to top,
carefully covering the inner sides of them with pitch so that they will
reject moisture. Both at the bottom and at the top above the vaulting
they should have airholes.
3. Then, whitewash them with lime and water so that they will not reject
the rendering coat of burnt brick. For, as they are dry from the loss of
water burnt out in the kiln, they can neither take nor hold the
rendering coat unless lime has been applied beneath it to stick the two
substances together, and make them unite. After spreading the rendering
coat upon this, apply layers of burnt brick mortar instead of sand
mortar, and finish up all the rest in the manner described above for
stucco work.
4. The decorations of the polished surfaces of the walls ought to be
treated with due regard to propriety, so as to be adapted to their
situations, and not out of keeping with differences in kind. In winter
dining rooms, neither paintings on grand subjects nor delicacy of
decoration in the cornice work of the vaultings is a serviceable kind
of design, because they are spoiled by the smoke from the fire and the
constant soot from the lamps. In these rooms there should be panels
above the dadoes, worked in black, and polished, with yellow ochre or
vermilion blocks interposed between them. After the vaulting has been
treated in the flat style, and polished, the Greek method of making
floors for use in winter dining rooms may not be unworthy of one's
notice, as being very inexpensive and yet serviceable.
5. An excavation is made below the level of the dining room to a depth
of about two feet, and, after the ground has been rammed down, the mass
of broken stones or the pounded burnt brick is spread on, at such an
inclination that it can find vents in the drain. Next, having filled in
with charcoal compactly trodden down, a mortar mixed of gravel, lime,
and ashes is spread on to a depth of half a foot. The surface having
been made true to rule and level, and smoothed off with whetstone, gives
the look of a black pavement. Hence, at their dinner parties, whatever
is poured out of the cups, or spirted from the mouth, no sooner falls
than it dries up, and the servants who wait there do not catch cold from
that kind of floor, although they may go barefoot.
CHAPTER V
THE DECADENCE OF FRESCO PAINTING
1. For the other apartments, that is, those intended to be used in
Spring, Autumn, and Summer, as well as for atriums and peristyles, the
ancients required realistic pictures of real things. A picture is, in
fact, a representation of a thing which really exists or which can
exist: for example, a man, a house, a ship, or anything else from whose
definite and actual structure copies resembling it can be taken.
Consequently the ancients who introduced polished finishings began by
representing different kinds of marble slabs in different positions, and
then cornices and blocks of yellow ochre arranged in various ways.
2. Afterwards they made such progress as to represent the forms of
buildings, and of columns, and projecting and overhanging pediments; in
their open rooms, such as exedrae, on account of the size, they depicted
the façades of scenes in the tragic, comic, or satyric style; and their
walks, on account of the great length, they decorated with a variety of
landscapes, copying the characteristics of definite spots. In these
paintings there are harbours, promontories, seashores, rivers,
fountains, straits, fanes, groves, mountains, flocks, shepherds; in some
places there are also pictures designed in the grand style, with figures
of the gods or detailed mythological episodes, or the battles at Troy,
or the wanderings of Ulysses, with landscape backgrounds, and other
subjects reproduced on similar principles from real life.
3. But those subjects which were copied from actual realities are
scorned in these days of bad taste. We now have fresco paintings of
monstrosities, rather than truthful representations of definite things.
For instance, reeds are put in the place of columns, fluted appendages
with curly leaves and volutes, instead of pediments, candelabra
supporting representations of shrines, and on top of their pediments
numerous tender stalks and volutes growing up from the roots and having
human figures senselessly seated upon them; sometimes stalks having only
half-length figures, some with human heads, others with the heads of
animals.
4. Such things do not exist and cannot exist and never have existed.
Hence, it is the new taste that has caused bad judges of poor art to
prevail over true artistic excellence. For how is it possible that a
reed should really support a roof, or a candelabrum a pediment with its
ornaments, or that such a slender, flexible thing as a stalk should
support a figure perched upon it, or that roots and stalks should
produce now flowers and now half-length figures? Yet when people see
these frauds, they find no fault with them but on the contrary are
delighted, and do not care whether any of them can exist or not. Their
understanding is darkened by decadent critical principles, so that it is