THE STONE-WORKING
We here begin to deal with the more technical rather than the purely
artistic view--the crafts as well as the arts. Connected with the
last chapter is the study of the materials and methods used for the
architecture.
Limestone was the main material of the land, the Eocene cliffs fencing
in the Nile valley along four hundred miles. The two finest kinds are
the Mokattam stone opposite the pyramids, which is perfectly uniform
and free from splitting or flaws; and the hard silicified stone
occurring at Tell el Amarna and elsewhere. The next commonest material
was soft sandstone from Silsileh, used generally after the middle of
the XVIIIth dynasty, especially in the Thebaid. The less usual stones
are the red granite of Aswan, which was used from the Ist dynasty
onwards; the quartzite sandstone of Gebel Ahmar near Cairo, begun
on a large scale by the XIIth dynasty; basalt from Khankah and other
eruptions, used in the IVth and XIXth dynasties; alabaster from the
quarries near Tell el Amarna; and diorite, used by the pyramid builders
only.
The quarrying of the limestone was usually by large galleries run into
the best strata. Blocks of two or three feet in size were cut out by
picking a trench wide enough for the arm to pass downward around the
block, and then inward below it, until it could be cracked away from
the bed. The blocks were thus cut out in regular rows, from top to
bottom of the gallery face. The same method is still kept up in the
open-air quarry at Helwan. For larger blocks a trench eighteen inches
wide, in which the workman could pass, was cut around the block. In
the sandstone quarries the same mode of cutting was followed, only the
quarry was open to the sky. So carefully was inferior stone rejected,
that instead of following cracks in the rock, a wall of stone was left
on each side of a crack; and such walls, each containing a fissure,
divide the quarry to its whole depth.
The granite was first obtained from loose water-worn blocks at the
Cataract, a great advantage of such a source being that any cracks are
made visible. Later it was quarried in the bed; a large mass still in
the quarry has been trimmed and marked across to be cut up for shrines
or sarcophagi. The early mode of fissuring was by cutting a groove and
jumping holes through the thickness of the stone, to determine the
direction of the fissure. Probably the active force was dried wood
driven in and wetted, as there is no trace of bruising by metal wedges
on the sides of the groove. In later times, instead of holes, mere
pockets were sunk rather deeper in the groove to hold the splitting
agent.
For cutting passages or chambers in rock, the method was to make a
rough drift-way, then finish a true plane for the roof, next mark an
axis upon the roof plane, trim the sides true to the distance from a
plumb bob held at the axis, and finally smooth the floor to a uniform
distance from the roof. In a rock chamber the roof was finished first,
and a shaft was sunk to the intended depth of the chamber to mark it
out.
The surfaces of rock and of dressed stones were picked smooth by a
short adze, with cuts crossing in all directions. The edges of a stone
were first dressed true, and then the space between was referred to the
edges. To do this, two offset sticks with a string stretched between
the tops of them were stood on the edges, and a third offset was used
to test the depth to the face, so as to see how much was to be cut
away. For larger stones, a diagonal draft-line was cut true as well as
the edge drafts, so as to avoid any twist. The face was finally tested
with a portable plane smeared with red ochre, and wherever that left a
touch of red, the stone was cut down; this was continued until the red
touched at intervals of not more than an inch. This was the quality
of face for joints; but it was further smoothed by grinding on outer
finished surfaces. The rough hewing of rock tombs was generally done
with mauls of silicified limestone, which is found as nodules left on
the surface.
The granite and hard stones were also sawn, and cut with tubular
drills. The saws were blades of copper, which carried the hard cutting
points. The cutting material was sand for working the softer stones,
and emery for harder rocks. As far back as prehistoric times, blocks
of emery were used for grinding beads, and even a plummet and a vase
were cut out of emery rock (now in University College). There can be no
doubt, therefore, of emery being known and used.
The difficult question is whether the cutting material was used as
loose powder, or was set in the metal tool as separate teeth. An actual
example was found at the prehistoric Greek palace of Tiryns. The hard
limestone there has been sawn, and I found a broken bit of the saw
left in a cut. The copper blade had rusted away to green carbonate;
and with it were some little blocks of emery about a sixteenth of an
inch long, rectangular, and quite capable of being set, but far too
large to act as a loose powder with a plain blade. On the Egyptian
examples there are long grooves in the faces of the cuts of both saws
and drills; and grooves may be made by working a loose powder. But,
further, the groove certainly seems to run spirally round a core, which
would show that it was cut by a single point; and where quartz and
softer felspar are cut through the groove floor runs on one level, and
as the felspar is worn down by general rubbing, the quartz is actually
cut through to a greater depth than the softer felspar. This shows that
a fixed cutting point ploughed the groove, and not a loose powder.
Also, the hieroglyphs on diorite bowls are ploughed out with a single
cut of a fixed point, only one hundred and fiftieth of an inch wide,
so it is certain that fixed cutting points were used for hand-graving.
There is no doubt that sawing and grinding with loose powder was the
general method, but the use of fixed stones seems clearly shown by the
instances above.
The large hieroglyphs on hard stones were cut by copper blades fed
with emery, and sawn along the outline by hand; the block between the
cuts was broken out, and the floor of the sign was hammer-dressed, and
finally ground down with emery. Hammer-dressing was largely used in all
ages on the hard stones; the blows crushed the stone to powder, and
the stunning of the surface was often not quite removed by grinding,
and shows as white spots. The hammer was usually of black hornstone, a
tough amorphous quartz rock.
The methods of placing the stones in the building have been often
debated. The foundations were usually laid on a bed of clean sand, and
this enabled the whole course to be accurately adjusted level to begin
with. For temples, it seems most likely that the interior was filled
with earth as the building advanced; and thus the walls, drums, and
architraves could be as easily dealt with as on the lowest course.
This plan is successfully used at Karnak in present repairs. But where
stones needed to be raised for a pyramid or a pylon, some staging was
required. Remains of a massive brick slope still stand against each
face of the unfinished pylons at Karnak. This, however, is only the
general mass of the staging, and the actual steps for the stones must
have been of stone, as brick would crumble to powder if any lifting
work was done directly upon it.
[Illustration]
For short blocks a cradle of wood was used, of which many models have
been found in foundation deposits along with model tools. On tilting
this to one end, and putting a wedge beneath it, it could be rocked
up the slope, and so gradually raised, first to one end and then to
the other. For large blocks, the actual lifting was probably done by
rocking up. If a beam be supported by two piles near the middle, a
small force will tilt it up clear of one pile; on raising that pile
the beam may be tilted the other way, and the lower pile raised in its
turn. Thus rocking from pile to pile, a beam can be quickly raised till
it is high enough to be moved on to the next step. It was probably thus
that the fifty-six granite beams, weighing over fifty tons each, were
raised in the pyramid of Khufu.
The obelisks were transported on great barges, as shown in the
sculptures. The method of raising such stones is partly explained
by an account of setting up colossi of Ramessu IV. A causeway of
earth was made sloping up for a length of a quarter of a mile; it
was ninety-five feet wide, and one hundred and three feet high on
the slope, probably about sixty or seventy feet vertically, as the
slopes were held up steeply with facings of timber and brushwood. The
purpose of this evidently was to raise the great block by sliding on
its side up the slope, and then to tilt it upright by gravity over
the head of the slope. How the mass would be turned we have nothing
to show, but probably the simplest way, by gradually removing earth,
would be followed. By next ramming earth beneath the obelisk as it lay
on a slope, it would be quite practicable to force it forward into an
upright position.
After a building was finished the sculpturing of its walls had to be
executed. For this, a long training of sculptors was needful, and
the art schools filled an important part in education. The simplest
subjects of outlines in limestone were a first step, the sign _neb_
requiring a straight and a curved line only. After the geometric forms
came studies of heads and of hands. In fig. 88 we see how, after a
fair control of the graver had been attained, there was still much to
be learned in detail and harmony before the artist could be trusted to
decorate a temple.
Statuary also needed a long training. The work was first marked out
in profile of the front and sides, and then cut along these outlines,
as in the rock-crystal figure (fig. 89), where the outlines at right
angles have been cut, but the corners are yet unrounded. In the block
for the head of a lion (fig. 90) the various planes have been already
cut for the face, before attempting any rounding. The limestone head
(fig. 91) shows a further stage, where the general rounding is done,
but the details of the lips, ears, eyes, and eyebrows are yet left in
the block. All of these stages needed incessant practice, and years
must have been spent in training in the schools before final work was
undertaken.
[Illustration: STONE VASES
87. A-H. Prehistoric
J. VIth dynasty
K. XIIth dynasty
L, M. XVIIIth dynasty]
Turning now to stone-work on a smaller scale, the hardest materials
were wrought for vases in the prehistoric age. In the first
civilisation, basalt, syenite, and porphyry were in use as well as the
softer stones, alabaster and limestone. The later civilisation brought
in slate, coloured limestone, serpentine, and lastly diorite, which
continued to be the favourite stone into the pyramid age. The main
differences of form are shown in fig. 87. The earlier type of vase
is the standing form F, with a foot, and no piercing for suspension.
The later prehistoric age brought in the suspended stone as well as
pottery vases. The main types were A, B, D, E, G, H, and lastly C,
cut out of coloured marbles, of syenite, and of basalt. All of these
vases were cut entirely by hand without any turning, or even any
circular grinding, on the outside. The polish lines cross diagonally
on the curved sides, and the slight irregularities of form, though
imperceptible to the eye, can be felt by rotation in the fingers. The
greatest triumph of this stone-work is the vase from Hierakonpolis
in black and white syenite, of the type A, E, two feet across and
sixteen inches high, which is highly polished, and hollowed out so
thin that it can be lifted by one finger, though if solid it would
weigh four hundred pounds. The interior of these vases was ground out
with stone grinders fed with emery, and in softer stones cut out by
crescent-shaped flint drills.
[Illustration: METHODS OF SCULPTURE
88. Trial piece of learner
89. Rough drafting
90. Lion’s head drafted
91. Head nearly finished]
The historic times show a continual decline in the quality of the stone
used. In the Ist dynasty the hard stones decreased, and the softer
slate and alabaster were more common. In the pyramid age only diorite
continued in use among the hard materials, and that but rarely compared
to soft stones; while in the XIIth and XVIIIth dynasties, beyond an
occasional vase of obsidian or serpentine, nothing is seen but the soft
alabaster. The form J belongs to the VIth dynasty. K is a type which
descends from the Ist dynasty, but in this form wide at the top belongs
to the XIIth, after which it disappears. L and M are of the XVIIIth
dynasty.
Amulets of fine stone were used from prehistoric days onwards. Of
the early ones, the bull’s head is the commonest, made of carnelian,
haematite, or glazed quartz. The fly is made of slate, lazuli, and
serpentine in prehistoric times, and of gold in historic jewellery. The
hawk is found of glazed quartz and limestone, the serpent of lazuli
and limestone; the crocodile, the frog, the claw, the spear-head are
all found in prehistoric use. In the Old Kingdom, small amulets of
carnelian or ivory were usual; the forms are the hand, the fist, the
eye, lion, jackal-head, frog, and bee. In the Middle Kingdom the more
usual material was silver or electrum. The New Kingdom used amulets but
little; the great profusion comes from the mummies of the Saite time,
when dozens may be found on one body. The great variety of forms and
materials would require a volume to explain them.
Beads were used from prehistoric times. The hard stones were cut
then--quartz, amethyst, agate, carnelian, turquoise, lazuli, haematite,
serpentine, as well as glazes on quartz and on paste. Glazed pottery
beads became the more usual in historic times; glass beads were made
from the XVIIIth dynasty onward, and hardly any other material was used
in Roman times. There are hundreds of varieties known, and an accurate
knowledge of their dates is essential in excavating.
Flint was worked to the highest perfection in the prehistoric age, and
continued in use till Roman times. Strictly, it is chert rather than
flint, as the beds in which it is found are of Eocene limestone. But in
general appearance and nature they are closely the equivalent of the
chalk with flints in England, only harder. The prehistoric forms are
shown in fig. 92. They exceed the flint-work of all other countries
in the regularity of the flaking, the thinness of the weapon, and the
minute serration of the edges. At present such work is entirely a lost
art, and we cannot imagine the methods or the skill required to produce
such results. Besides the weapons, flint armlets were made, chipped
out of a solid block, yet no thicker than a straw. These were ground
with emery finally to smooth them for wearing. Flint was commonly used
down to the XIIth dynasty for knives, but all the dynastic working is
far inferior to the earlier. In the XVIIIth dynasty, and later, sickle
teeth were still made of flint; and flakes were chipped and used in
abundance at some centres in the Roman period.
[Illustration: FLINT-WORKING
92. Knives and lances of the best prehistoric work]
Before leaving the stone-working we may note the accuracy of work,
as this is better seen here than in any other subject. The highest
pitch of accuracy on a large scale was reached under Khufu in the IVth
dynasty; his pyramid had an error of less than ·6 of an inch on its
side of 9069 inches, or 1 in 15,000; and its corners were square to
12″. A change of temperature during a day would make larger errors
than this in a measuring-rod. The accuracy of levelling, and of finish
of the stones, is on a par with this; joints over six feet long are
straight to a hundredth of an inch. The pyramid of Khafra has three
times this error, varying 1·5 inch on 8475, and 33″ of angle. That of
Menkaura is worse, being on an average 3 inches out on 4154, and 1′ 50″
of angle. At Dahshur the errors are 3·7 on 7459 inches base, and 1·1 on
2065, with angular errors of 4′ and 10′. In smaller work, a beautiful
example is the granite sarcophagus of Senusert II, which is ground flat
on the sides with a matt face like ground glass, and only has about
a two-hundredth of an inch error of flatness and parallelism of the
sides. The later ages, so far as we know, have left nothing that can be
compared with the accuracy of the early dynasties.