Chapter THE SECOND: Man as the MIMIC of Nature (2)

Mr. Thomas Beddoes, an African trader, and traveller, draws my attention to this bridge of forked branches; and tells me also that in the Agowe district, but far inland from the banks of this river, he came upon a primitive suspension bridge partly made with very thick vines--vines as thick as a man’s leg--which were joined together into a couple of natural ropes long enough to be suspended from trees over a creek about two hundred feet wide. Perhaps a yard separated them, and they were parallel to each other. When anchored to the trees at a height of four or five feet above the bank, they form the upper part or parapet of the bridge. As for the footway, its bearers were saplings--young trees from ten to twelve feet long and three or four inches in diameter; they were lashed together into a continuous runner, and two such runners were laid from the banksides over the creek, to carry a hurdle pathway of canes or sticks. Then the upper part of the bridge was braced to the saplings with thin vines, which were tied to their supports at intervals of about a foot, and which served the purpose of suspension rods, for they counteracted the strain on the saplings when a native crossed the narrow footway.

It would be easy to write much more about primitive swing bridges, but enough has been said to stimulate thought and discussion. Not one of them has a brighter intelligence than that which we find in many prehistoric handicrafts.

VIII

NATURAL ARCHES--THEIR SIGNIFICANCE AND THEIR
INFLUENCE

Long before the germ of humanity in some anthropomorphous apes became slowly fertile in a mysterious gestation, Nature had weathered many rocks into hollowed and vaulted shapes. Some were yawning sea-caves, whose arched mouths gulped in the tidal waves, and whose caverned bodies gurgled or boomed with the noise of deepening water.[55] Others were vaults gradually fretted into being by subterranean torrents, such as we find to-day at Saint-Pons, in the Cevennes, where the river Jaur is nourished by an abundant spring which in a second, through the mouth of a low-arched cavern, pours a thousand litres of fresh, sweet water. Others, again, were genuine arched bridges, such as we find to-day in the Pont d’Arc, over the river Ardèche (p. 6). In England we have several such bridges, notably the Durdle Door on the coast at Lulworth, whose arched span must owe at least a part of its shape to the troubled action of sea-waves. “La Roche Percée” at Biarritz--a crinkled, lava-like formation--is inferior to our Durdle Door; and “La Roche Trouée,” near Saint-Gilles Croix-de-Vie, though remarkable as a square-headed aperture, has a lower place still in the pontine work done by Nature.[56]

Perhaps the most wonderful rock-bridges are those at Icononzo, in New Grenada, over the torrent of Summa-Paz. There are two, and one of them soars up and up to a crown that spans the water at an altitude of ninety-seven metres. How could men of genius fail to be architects when Nature set before their eyes great vaults, not only varied in shape, but at times of a stupendous height? In different ways she produced surbased arches, pointed arches, semicircular arches, all more or less ragged in their outlines, but each a model for progressive mimicry and adaptation.

Here is not the place to dally with the causes of their formation, such as uneven weathering and the scour of running water subject to high tides or to terrific floods. As rivers in the course of many ages deepen and widen their channels, they reach now and then a strata of fissured rock, and their eating action is very rapid when they are able to undercut the softer rocks by fretting their way along apertures or crevices. Many an earthquake has made such inlets for river water, and earthquakes may have shattered some rocks into vaulted shapes. Whether glaciers have played a part in the hollowing of rocks into arched caves and bridges I do not know; but rock-basins are attributed to the erosive power of glaciers, so why not some rock-bridges also? It is a question over which geologists ought to quarrel as they did over rock-basins.[57]

But the main point is that the archways made by Nature not only suggested the arched bridge of handicraft, but heralded all the lovely styles of building which have used vaults, domes, turrets, towers, spires, steeples, and arched openings--gateways, porches, and windows. There is a rival art, as we know, an art which has glorified the long lintel-stone carried by pillars; but it has never won from the genius of great men the highest technical inspiration. To it we owe much work of a noble dignity, but in the powerful aspiration of this work there is but little upward flight; it is not near at once to the point of heaven and the point of home. In fact, its masterpieces weigh down heavily on the earth instead of rising towards the light. Not till we come to genuine _archi_tecture--to the art that employs arches and vaults and domes--do we find united in the same edifice a majestic weight and a buoyant fervour. This union of qualities may be found in a supreme Roman bridge, such as the Puente Trajan at Alcántara, but it reigns most beautifully in a Gothic cathedral, whose bulk, earth-bound and vast, has in it what Goethe defined as a petrified music, lofty and spiritual. Rome built for man and the ages, while Gothic art has a symphonic ardour expressed in a creed of hope that transcends all terrene things.

The work done by Nature in various archways, some pointed and many round-headed, is a surprise to many persons. Yet Nature’s custom is to build in curves and circles, as in the trunks of trees, and the shapes of flowers, and the forms of birds’ nests. She hates angles, and particularly right angles; these she makes in her moods of violence, when she flashes into zigzag lightning, or splinters trees and rocks with an earthquake. We ourselves are accustomed from early youth to squared shapes in handicraft, yet our actions often speak to us of mankind’s primitive fondness for circular huts and round pit-dwellings. We find it difficult to walk forward in a straight line, the steps we take having a tendency to curve; and untaught boxers never hit straight from the shoulder, their arms swing in segments of a circle. Art students, again, begin by drawing “too round,” so they have to be shown how “to square their touch.” Are you tempted to believe that the spinning of our globe has transmitted to all living things the routine of its movement?

In any case, let us keep well in mind the different symbolism implied by curves, angles, straight lines, and circles. Squares and oblongs denote repose and weight, while circles and curved lines are identified with everything in the universe that denotes life, mystery, intelligence, fertility, light and heat, movement and speed, and space illimitable. Human progress itself is a circular ascent along the finest spiral lines, for civilization as a whole never comes back to the same conditions, but creeps above them to some trivial extent. The greatest circular or rounded shapes are the sun, the full moon, our own little world, the human skull, and the human heart; eggs, flowers, nests, the shapes of bones, and the wheel, without which dilatory progress would have been far and away too pedestrian. The first wheel was a rolling stone; afterwards men noticed that a log touched by accident on a hill rolled down for some distance; and at last a person of genius cut solid sections from a tree-trunk and made the earliest wheel of handicraft.

Just one more point ought to be noticed with sympathetic care: that arches in art are more suggestive than circles; they have the mystery of a beautiful part taken from a whole--a whole that looks methodical. We feel this mystery whenever we watch how the moon grows from a silver crescent into a radiant circle. A thing complete dulls an attention that looks on, whereas growth or the suggestion of growth has the stimulus of hope and faith. To culminate is to begin a decline. Even the circle of the sun would be tiresome but for the grey days that renew a truism into a gracious truth. This explains why arches in art make an appeal to the imagination that circles never equal. For example, wheel-windows in Gothic architecture never have the magic of pointed windows. Our eyes travel around them and cannot escape in a flight upwards. Nature, then, when she produced arches, brought into the world a very noble inspiration, and therefore very remote from the dull and slow mimicry of mankind.

In fact, the earliest known vaults of handicraft have but a trivial age in the vast antiquity of human life. Let us take a rapid glance at them, so as to note their rudimentary construction. They are built not with stones directed towards the intrados, but with stones in horizontal courses that jut out one beyond another, just as Nature’s archways in stratified rocks have a succession of layers. At Abydos, one of the most ancient cities of Upper Egypt, there is a vault of this primitive sort in the temple of Rameses the Second, who reigned for sixty-seven years, from about 1292 to about 1225 B.C.[58] Another is found at Thebes in the temple of Ammon-Rē, but the most ancient specimen of all is at Gizeh, in the great pyramid of Menkaura. Now Menkaura belonged to the Fourth Dynasty, so that his date is more than 3000 years B.C. His sepulchral chamber is ceiled with a pointed arch--not a true arch, of course, the stones being merely cantilevers opposite to each other, with their undersides cut to the pointed shape. To understand the structural method, close your hands together at their full length, then open them gradually into the form of a pointed arch: the united finger-tips represent the apex of the vault, and the curving fingers represent the long archstones. Here is a departure from the horizontal layers of stone, but with these also pointed arches have been built.

For instance, Italy has a very good example at Arpino, in Campania. “Arpino occupies the lower part of the site of the ancient Volscian town of Arpinum, which was finally taken from the Samnites by the Romans in 305 B.C..... The ancient polygonal walls, which are still finely preserved, are among the best in Italy. They are built of blocks of pudding-stone, originally well jointed, but now much weathered. They stand free in places to a height of eleven feet, and are about seven feet wide at the top. A single line of wall, with mediæval round towers at intervals, runs on the north side from the present town to Civita Vecchia, on the site of the ancient citadel. Here is the Porta dell’ Arco, a gate of the old wall, with an aperture fifteen feet high, formed by the gradual inclination of the two sides towards each other.”[59]

This ancient gate has a pointed arch; it belongs to the so-called “Cyclopean style.” Sir William Smith gives an illustration of the Porta dell’ Arco, and refers to “the very singular construction,” in which successive courses of stone “project over each other till they meet, so as to form a kind of pointed arch.” Yet the construction is in no respect very singular, being the simplest way in which rude arches can be copied from Nature’s models. With toy bricks of wood a child can build a Porta dell’ Arco.[60] On the other hand, art and science go together in the building of an arch with voussoirs and keystones. A long evolution separates this workmanship from the gateways at Arpino and Tiryns and Mycenae, though we cannot follow it through its gradual improvements. It is an evolution with many breaks, many related forms having perished; but experts note a difference between the Porta dell’ Arco at Arpino and similar vaults both at Mycenae and at Tiryns, where the craftsmanship dates from the Heroic Age in Greece.

The main entrance at Mycenae is called the Lion Gate, from the famed triangular arch and relief above its huge lintel-stone. The arch belongs to the method of laying stones in horizontal courses that jut out towards each other across an opening; and the decorative sculpture represents two lions that stand face to face; they are separated by a pillar and their front legs rest on a low altar-like structure that supports the pillar. The same device occurs in cut gems and in goldsmith’s work of the Mycenaean age; and the lions recall to memory those with which some Chinese bridges have been ennobled (pp. 127, 311).

Even more remarkable are the beehive tombs at Mycenae; there are eight in all, and some others are found in the neighbourhood. Pausanias regarded them as the places where Atreus and his sons hid their treasures, but now they are looked upon as the tombs of princely families. The most important of them, just outside the Lion Gate, is called the Treasury of Atreus. It has two rooms, a square one cut in the rock, and a round one with a pointed dome. This chamber is fifty feet in height and in diameter; we go to it along a horizontal passage twenty feet wide and a hundred and fifteen feet long, with side walls of squared stone sloping up to a height of forty-five feet. “The doorway was flanked with columns of alabaster, with rich spiral ornament, now in the British Museum; and the rest of the façade was very richly decorated, as may be seen from Chipiez’s fine restoration. The inside of the vault was ornamented with attached bronze ornaments, but not, as is sometimes stated, entirely lined with bronze. It is generally supposed that these tombs, as well as those excavated in the rock, belong to a later date than the shaft tombs on the Acropolis.”[61]

In the Treasury of Atreus there are two points that interest architects more than any others. The first is the contrast between admirable decoration and hugely primitive stonework; and the other is the fact that the annulary courses forming the domed and circular chamber have this particular character, that the lateral joints of the stones hardly tend at all towards the centre. Moreover, again and again the stones are separated by a space, and this interval is filled up with small rubble which seems to have been pressed together with the greatest care. These irregular courses, whose inside diameter grows less and less as the circular wall grows higher and higher, forms at last a sort of pointed dome over the great tomb. M. Degrand says very well: “A vault of these proportions must count as a memorable work. Its construction here and there makes use of colossal stones, and it subsists almost intact after more than thirty centuries of existence. At a pinch its architect and workmen could have erected some masonry bridges in accord with the same technical method.”

In wide arches of this sort the resistance of good mortars would have been called upon to play the leading part; but in arches of narrow span the stones could have been used dry, and such arches may well have displaced many a primitive footway of logs that rested on stone piers.

The Egyptians built some real arches, not with long stones carefully shaped into segments of a circle, such as we find in some Chinese bridges (pp. 313-14), but with hewn blocks whose joints converged toward a common centre. In Ethiopia, for example, in one of the pyramids of Meroe, there is a semicircular arch composed of voussoirs; and two pyramids at Gebel Barkel have arched porticoes with voussoirs that tend to one point. Their shapes differ, one arch being pointed and the other round-headed.[62] The pyramids of Gebel Barkel are puny in style, and belong to a very late date in old Egyptian history.

As we have seen, a triangular arch may be studied above the Lion Gate at Mycenae. Triangular arches are uncommon, but Brangwyn has chosen a good example of a much later date from Kashmír. The builders found it easier to set up a triangular scaffold than a rounded one.

As for the semicircular arch, early examples of it have been discovered in Asia Minor, among the ruins of Phrygian cities; in Acarnania, the most westerly province of ancient Greece; and also in that part of Central Italy where the Etruscans, by their powerful civilization, heralded Rome. It was in Etruria that Rome cradled her infancy, for she borrowed from the Etruscans many of her building methods and many of her civil institutions, both religious and political. Among the gleanings that she harvested we find the round-headed arch, which became a symbol of Roman conquest and colonisation. Perhaps it was employed at Rome for the first time in those great sewers, extant still, which were attributed to the statesmanship of Lucumo Tarquinius, the legendary man of wealth who with his wife and retinue migrated in a splendid manner from Etruria and became a Roman citizen. If the sewers were built about 600 years B.C., then the history of round-headed vaults, as Rome collected from many nations the toll of enlightened obedience, extended over more than a thousand years.

In the next chapter we shall try to understand the Roman genius, but here we must recall to mind two preliminary points: one is the aboriginal arch of tree-trunks that Cæsar found in Gaulish bridges (pp. 70, 72), the other is the fact that the Romans left in Britain a version of their round-headed arch that is simpler and more rustic than any other. It was copied frequently by mediæval bridge-builders, and to-day many of the copies are known locally as Roman. Brangwyn represents one of these imitations in Harold’s Bridge at Waltham Abbey.

Perhaps this bridge may date from Harold’s time, but it is a feeble thing in comparison with the Roman example near Colne, Clitheroe, whose simple and effective structure is bolder in aspect than the New Port at Lincoln, a genuine Roman gateway. There is but one arch in the Roman bridge near Colne, and its voussoirs have no masonry above them, the footway being protected by large cobbles which are easy to displace when they become outworn. Perhaps the width of this bridge may have been great enough for Roman wheels and British chariots, but I doubt if a coster with his cart would make the crossing.

Along the ancient tracks of Lancashire there are many single-arch bridges with a Roman aspect, but without an authentic air of stalwart dignity. The one near Colne looks genuinely Roman, while the others speak to me of a Roman tradition enfeebled in much later times by a rather timid craftsmanship. Mr. C. S. Sargisson has examined these bridges carefully, and from him I have received some excellent photographs.

A bridge belonging to the same school is to be found at Monzie, near Crieff, in Perthshire; there are several in North Wales, the best example being Pandy Old Bridge at Bettws-y-Coed; and a good English specimen, quite as entertaining as Harold’s Bridge at Waltham, should be noted at Hayfield. Nothing can be simpler than this use of a single rough ring of voussoirs; and it justifies the inference that Roman pontists were niggardly in Britain, since they stereotyped a narrow bridge without parapets, and erected no tremendous aqueduct and no bridge of enduring fame, such as we find elsewhere in Europe. If Rome had foreseen the future history of Britain, and had given way to jealousy, she could not have been more parsimonious in her British bridge-building.

FOOTNOTES:

[34] The orang in the Eastern islands, for example, and the
chimpanzee in Africa, build platforms on which they
sleep.

[35] White of Selborne notes this fact. And Darwin notes
two others of equal interest. He says: “The orang is
known to cover itself at night with the leaves of the
Pandanus; and Brehm states that one of his baboons
used to protect itself from the heat of the sun by
throwing a straw mat over its head. In these several
habits we probably see the first steps towards some
of the simpler arts, such as rude architecture and
dress, as they arose among the early progenitors of
man.” Darwin refers to architecture as well as dress
because of an earlier sentence on the platforms built
by anthropomorphous apes.

[36] But for this habit we should be less horrified by the
acts of German “culture” in a time of war. I add this
note to my proofs, September 26, 1914.

[37] Better in many respects, but not in all; for as
Darwin points out, it was the self-condoning mind of
man, not the instinct of any brute beast, that came
to use infanticide as a custom. “The instincts of
the lower animals are never so perverted as to lead
them regularly to destroy their own offspring.” Only
arguments can choose and approve unnatural habits.

[38] “Daily Telegraph,” September 8, 1913, p. 5.

[39] “A Book of North Wales,” by S. Baring-Gould, pp. 2-3.

[40] These calculations can be studied at the British
Museum side by side with an excellent model of
Stonehenge. On the supposition that Stonehenge was
a sun-temple, its date has been astronomically
determined as about 1680 B.C., with a possible error
of two centuries either way.

[41] Emiland Gauthey, “Traité de la Construction des
Ponts,” A.D. 1809-1816.

[42] “The Travels of Marco Polo.” Everyman’s Library, p.
315. It is to be remembered that Marco Polo’s “paces”
are geometric.

[43] Professor Fleeming Jenkin’s “Essay on Bridges.”

[44] For criss-cross piers, see Index.

[45] Forked boughs were used in the building of roofed
walls, and bent trees in the building of gabled cabins.

[46] Sir Ray Lankester, “Daily Telegraph,” August 27, 1913,
p. 6.

[47] Robert Munro’s “Archæology and False Antiquities,” p.
12.

[48] Tacitus remarks of these wild tribesmen: “They are
accustomed to make artificial caves in the ground, and
they cover them with great heaps of dung, so as to
form a shelter during the winter, and a storehouse for
the produce of the fields. For in such dwellings they
moderate excessive cold, and if at any time an enemy
should come, he ravages the parts that he can see, but
either discovers not such places as are invisible, and
subterraneous, or else the delay which search would
cause is a protection to the inmates.”

[49] Boyd Dawkins, “The British Lake Village,” 1895; Sidney
O. Addy, “The Evolution of the English House”; “The
Times,” September 19, 1895; “Manchester Guardian,”
September 22, 1896; and A. Bulleid, “Somersetshire
Arch. and Nat. Hist. Society’s Proceedings,” 1894,
reprinted in 1895.

[50] The making of a Roman road was a formidable
enterprise. H. M. Scarth, in his “Roman Britain,”
relates how a portion of the Fosse Road at Radstock,
about ten miles south-west of Bath, was opened in
February, 1881, and that its work showed the following
details in constructive method. 1. Pavimentum, or
foundation, fine earth, hard beaten in. 2. Statumen,
or bed of the road, composed of large stones,
sometimes mixed with mortar. 3. Ruderatio, or small
stones well mixed with mortar. 4. Nucleus, formed by
mixing lime, chalk, and pounded brick or tile; or
gravel, sand, and lime mixed with clay. 5. Upon this
completed foundation the _summum dorsum_, or surface
of the paved road, was laid with infinite care. So the
men of a day built roads for the centuries, and were
proud to be servants to the unborn.

[51] Professor Fleeming Jenkin. If any reader wants to
continue the study of timber bridges, let him turn
to Colonel Emy and to the huge volumes compiled and
edited by Hosking. But it is clear enough that timber
bridges belong to the past; in these days they are
ludicrously out of joint with the needs of social
life, owing to the rapid advance which “progress” has
made in artillery, in high explosives, in airships,
and in aeroplanes.

[52] These date from about the year 1816, when Galashiels
Bridge was constructed. It was only 112 ft. in length.
But in 1819 Telford designed the Menai Bridge, in
which the span of the catenary is 570 ft. and the dip
43 ft. The success of this work gave rise to much
imitation, and in several places very great projects
were carried through with success. At Pesth, for
instance, the span was 666 ft., and at Fribourg 870
ft. But engineers, having no imagination and but
little prudence, went too far, so they had to retreat
from their cocksureness. Soon it became evident that
a long suspended bridge of metal suffered much from
the lateral oscillation caused by wind, and that its
flexibility made it unfit for railway traffic. “The
platform rose up as a wave in front of any rapidly
advancing load, and the masses in motion produced
stresses much greater than those which could result
from the same weights when at rest. Moreover, the
kinetic effect of the oscillations produced by bodies
of men marching, or even by impulses due to wind,
may give rise to strains which cannot be foreseen,
and which have actually caused the failure of some
suspension bridges. On the 16th of April, 1850, a
suspension bridge at Angers gave way when 487 soldiers
were passing, and of these 226 were killed by the
accident.”--Professor Fleeming Jenkin.

[53] From information kindly supplied by the Rev. O. M.
Jackson.

[54] “A Voyage to South America,” Antonio de Ulloa,
translated from the Spanish by John Adams, Fourth
Edition, Vol. II, p. 164.

[55] Such caves are frequent on the coast of Pembroke, in
the Little England beyond Wales. Lydstep Arch is a
far-famed example, and the Devil’s Punch Bowl, opened
within the area of a prehistoric camp by the falling
in of the roof, has an archway to the sea. “Bocherston
Mere is a very small aperture, which, like a widening
funnel, spreads out below into a large cavern. During
the prevalence of gales from the south-west, the sea,
driven by wind and tide in at the arched entrance,
is ejected through the upper hole in jets of foam
and spray some forty or fifty feet high, like geyser
spouts. The limestone naturally pierced with caverns
lends itself to be thus riddled and rent.”--S.
Baring-Gould, “Book of South Wales,” p. 196.

[56] There is no need to multiply examples, for every
reader must have seen how rocks have been vaulted,
and lands tunnelled, by underground rivers. At one
part of her course, for example, the Guadiana flows
underground for twenty miles, forming a vast bridge
above which 100,000 sheep can pasture.

[57] When the glacial theory of their formation was young
and argumentative it encountered at first a sneering
opposition from Sir Roderick Murchison, the famous
geologist, who in 1864 wrote as follows to Sir William
Denison: “In my anniversary address to the Geological
Society you would see the pains I have taken to
moderate the icemen, who would excavate all the
rock-basins by glaciers eating their way into solid
rocks.” But he failed to “moderate the icemen”; and
Sir Roderick himself, a few years before his death,
gave what is called “a tardy acquiescence” to their
evidence. He became a frigid iceman. As Dr. Robert
Munro has said, evidence which may be clear and
convincing to one trained mind may not have the same
effect on another--a fact which should at least warn
us to be tolerant in matters of opinion.

[58] Dates in Egyptian history are obscure, but these give
the period approximately.

[59] “Encyclopædia Britannica,” 11th edition, article
“Arpino.”

[60] M. Degrand, in his “Ponts en Maçonnerie,” draws
attention to the fact that arches of this elementary
sort have been discovered in Mexico where they
represent a dead civilization to which no date can
be assigned. Degrand draws his information from two
books; “Histoire du Royaume de Quito,” par Don Juan
de Velasco, Paris, 1840, and “Monuments anciens du
Mexique,” par de Waldeck et Brasseur de Bourbourg,
Paris, 1866. At Palanqué, in a building supposed to be
a temple of the sun, a large bay that opens into the
sanctuary has an elliptic arch formed with courses of
dressed stone that project one beyond the other: “_un
arc surbaissé formé d’assises de pierres de taille
posées avec une forte saillie les unes par rapport aux
autres._”

[61] “Encyclopædia Britannica,” article “Mycenae”; see also
Sir William Smith, “Dictionary of Greek and Roman
Geography”; and note what M. Degrand says in his
“Ponts en Maçonnerie.”

[62] See E. Degrand, Vol. II, p. 124; and see also the
“Traité d’Architecture,” by Léonce Reynaud.