The Wall

by Alistair Moffat

  ANOTHER GREAT WALL

  Stories of the Far East had filtered to Rome for generations. Trade brought spices, fine silks and tales of exotica. Hadrian himself had been to the Persian Gulf, perhaps a younger Trajan would have emulated Alexander the Great and led armies to India. Antoninus Pius is known to have received ambassadors from China, from the emperors of the Han dynasty. They too were interested in walls, and had been building them for some time. The Great Wall of China, with its broad walkways, crenellations and turrets dates very much later, having been built for the Ming dynasty in the sixteenth century. The wall that Hadrian and Antoninus may have heard about was in some ways more impressive. Built mostly of rammed earth and gravel, the walls raised to defend the northern borders of China had existed since c. 200 BC and the reign of the first emperor of all China, Qin Shi Huangdi. In all, these ran for an astounding 6,400 kilometres and are the largest man-made structures ever built. Perhaps Hadrian was impressed, even inspired.

  The symbolism invested by Hadrian in his Wall was not the only reason for its construction. The great labour was undertaken for several practical purposes. As in the German forests, clear demarcation – something unmissable – was important. In the new world of consolidation, being either side of the Wall would have real meaning – in the Empire and outside it. The Wall’s presence had military value (not as a fighting rampart: it was too narrow, not built to allow enfilading fire along its length and not meant to be defended like a medieval castle) in that it could prevent large numbers of enemy warriors from getting through it quickly. The Historia Augusta records a simple strategic rationale. The Wall was built qui divideret Romanos barbarosque. The sense of the verb, it has been persuasively argued, is stronger than merely to divide or separate. It really means ‘to force apart’ the Romans and the barbarians. And this reading becomes even more persuasive when the political landscape is looked at more closely.

  The Brigantes, the largest native kingdom in Britain, appears to have been a federation including the Carvetii in the Eden Valley in the east, and the Textoverdi, the Lopocares and the Corionototae along the banks of the Tyne. When King Venutius attempted to defend his huge hillfort at Stanwick, he called on help from outside, that is, from the north. Agricola’s lines of advance in AD 79 encircled the dangerous Selgovae, and the construction of the Sea-Wall down the Cumbrian shore clearly anticipated a threat from the Novantae in Galloway. By driving a concrete, heavily guarded and unmistakable frontier through the Hexham Gap, Hadrian forced apart this powerful alliance of the hill peoples of the north. Of course their kings could communicate, and it seems that sometimes they did succeed in inflicting damage, but the glowering presence of the Wall would prevent them from combining quickly and in force.

  Economic imperatives rarely lagged far behind military objectives in the Roman Empire. Just as in Germany, those passing through the Wall probably paid portaria, a tax on movement and goods. Cattle and sheep rustling in the hills and upland valleys of the north Pennines and the Cheviots was not the invention of the Border Reivers of the sixteenth century. Its origins were ancient, and a useful economic effect of the Wall was to prevent cross-border raiding almost entirely (or at least without a considerable outlay in bribery). At the height of the lawlessness of the 1570s and 1580s Elizabeth I of England’s council seriously considered rebuilding Hadrian’s Wall, rejecting the idea only on the grounds of cost.

  Much more danger appears to have lurked in the western districts around the Wall. There was thought to be no equivalent need for a Sea-Wall down the North Sea coast, and no outpost forts were built (at first) in the east. The Votadini were not only almost certainly friendly to Rome but also key providers of essential supplies to the large garrison. In the west it was different, and three forts were established in forward positions, at Birrens, Bewcastle and Netherby. The last was known as Castra Exploratorum, the Fort of the Scouts. Patrolling and intelligence gathering were clearly seen as necessary at that end of the Wall. If Hadrian hoped to force apart the barbarians, it seems that he meant to achieve it in the centre and the west. The balance of the garrison was weighted there. In the east, the Tyne was probably already a frontier between the Votadini and the peoples to the south.

  Perhaps because it was more settled, building began from the eastern end. And work began everywhere at once. Or so it must have seemed to the native peoples. No doubt exhibiting the impatience characteristic of those in high office, Hadrian will have demanded immediate action, and in the late summer of 122 progress would have been rapid and dramatic.

  SOUVENIRS

  Not long after it was completed, the Wall appears to have become a tourist attraction in Britannia. The Rudge Cup, the Amiens Skillet and the Staffordshire Skillet all carry the names of forts inscribed on them, usually around the rim of the vessel. All have a sequence of forts at the western end, and not the entire run. Like mugs with Blackpool or Bournemouth painted on them, they seem to have been popular. The survival of three artefacts of such an individual type is surely significant. Discovered recently, in 2003, the Staffordshire Skillet, or patera, has a name inlaid: Aelius Draco. Perhaps he was a soldier who served out his time on the Wall and his messmates had a memento made for him.

  Once the line of the Wall had been accurately surveyed and marked (the Roman military made extensive use of maps), the countryside burst into a frenzy of activity. Detachments of soldiers were despatched to quarries, woods, sandpits, rivers and streams to discover local suppliers of all manner of goods, to build limekilns, blacksmiths’ forges and workshops. Smoke from thousands of fires plumed into the Northumberland skies. Not until the Industrial Revolution seventeen centuries later would the landscape of the lower Tyne see such toing and froing.

  Three legions were commanded to build the Wall. The II Augusta, the VI Victrix and the XX Valeria Victrix represented a combined workforce of at least 7,000 men. Each legate will not have needed reminding that their men had been set to work in hostile country. Having left a cohort behind at their regional bases at York, Chester and Caerleon, the legions also required protection and their first action will have been to build secure quarters. In the midst of so much activity, it has been difficult to detect where they camped, but while use will have been made of existing forts, the construction of the Emperor’s Wall was a field exercise and his soldiers will have pitched their leather tents behind a palisade. Scouts no doubt rode out on regular patrols to anticipate enemy activity. There had been war in the north only three years before and, as each man worked, his weapons were not far away.

  The legions built the Wall because they had all the necessary skills. In addition to their primary role as heavy infantry, many men were also stonemasons, blacksmiths, carpenters and carters. And each legion was used to operating as a self-contained unit. Hadrian and Nepos decided to use this to advantage. Construction of the Wall was split up into legionary lengths of about eight kilometres, what was thought to amount to a season’s work. And there would be productive rivalry between the men of the II, the VI and the XX.

  Building was supervised by a Clerk of Works known as the Praefectus Castrorum. His first task was not to send gangs to the line of the Wall but to assemble all the logistical elements needed to make the project happen. It was very complex, and logistics were the key to success. As a general rule of thumb, for every one man building the Wall itself there were a further eight working to support him, supplying materials, digging ditches, watching the horizon for warbands of enemy horsemen.

  Gangs worked ahead of each other in a clear sequence. After the turf was cut out and preserved for later use, a shallow trench was dug along a line pegged out with cord by the surveyors. Flags, boulders and other large loose stones were brought forward by oxcart (certainly at the east end of the Wall where the ground was not difficult) and bedded into the clay or earth, making as level a foundation as possible. Where the Tyne was navigable, the river will have been used to bring up materials. Barges and ships were the largest form of bulk transport avail
able to the Romans. Meanwhile at the nearby quarries (the furthest from the Wall appears to have been Black Pasture, 1.3 kilometres from the fort at Chesters) men were clearing vegetation and throwing down bottoming to make hard standing so that they could get at the stone and get it out.

  More stonemasons probably worked at the quarries than on the Wall itself. With difficult journeys by oxcart and pack-horse over rough country and often uphill, it was vital to keep carriage weight to a minimum. Once stone had been levered or cut out with wedges, it was roughly sized according to its use. Ordinary Wall stones were manageable and could be loaded onto a cart or a pack-saddle by one man, occasionally two. These blocks of what is known as squared rubble were cut flush at one end (the best end, according to the grain) usually with a scappling hammer rather than a chisel and mallet. The blocks were then tapered away from the cut face into a blunted pear-shape. This was done to make it easier for the less skilled men at the Wall, allowing them to bed stones quickly, only having to present a keyed course on the outside; what we see now. The tapered end was set to the inside so that it bonded better with the rubble and clay core, and also did not touch its neighbours at the sides and need to be cut to fit. This method of working made for rapid progress.

  GANGS OF THE NEW WALL

  Within the legionary lengths, there were sectors run by each centurion. These were worked by gangs with strictly organised roles. It is estimated that at the site there were 30 men working as a unit, 15 on the north side and 15 keeping pace with them on the south. In each gang, 3 men laid courses of stones and beds of mortar, 4 mixed, kept wet and brought forward mortar, 3 filled the core while 4 provided clay to bond it and there was 1 general labourer, probably the youngest – the lad who would have made the tea if they had had any. Down at the quarry 55 men worked. Of these the vast majority both quarried and roughed out stones, and 10 or so worked on the discarded rubble, breaking it down so that it could be used to fill the core. These numbers say nothing about transport, wood-felling and scaffold-work, sand-quarrying or any of the myriad other tasks. They are the estimates of an experienced modern mason.

  The quarries mostly produced sandstone and gritstone, both sedimentary and easy to work. The whinstone from the Sill was usually too hard. Mortar was made from limestone and, happily, the eastern and central sectors appear to have a sufficient supply to hand. In the occasional slack moment, some of the masons at the quarries left inscriptions. At Haltwhistle Burn, the VI Legion made its mark, but nineteenth-century quarrying removed the lettering. North of Housesteads, at Queen’s Crag, there is an undated inscription which is certainly Roman, and at other places men carved a phallus and testicles – a symbol of good luck and no doubt the subject of ribald comparison.

  Up on the Wall the turrets and milecastles were built first. Perhaps this was decided because of the volatile nature of the area, perhaps it would also help with plotting the line of the Wall correctly. Archaeologists have been able to demonstrate this order of building because the turrets and milecastles were left with projections designed to bond with the incoming stretch of connecting Wall. Like the irregular edges of an unfinished jigsaw, the courses of stone stick out on either side.

  The most complex and difficult elements of each milecastle were the arched gateways. Teams of specialists quarried and assembled them. To cope with the additional structural stress, larger stones were needed for both the piers and the arches themselves. Some survivors have been found to weigh half a tonne. At the quarry, bursting hammers were used to shape the big blocks. With an axehead shape at one end and a flat sledgehammer face at the other, they could be worked quickly in the hands of an experienced man. Known as voussoirs, the wedge-shaped stones for the arch had to fit precisely, and a procedure called setting-out was used. Once all the faces had been cut roughly flush (finer work could be done at the site) the arch was, in essence, built lying on the ground with each stone set in its place and the necessary symmetry achieved. Good masons can judge these proportions by the eye. Once all was ready, the components of the arch were lifted onto a train of oxcarts. Much too heavy to be picked up by muscle-power, they were loaded by block-and-tackle hoists. These were sophisticated and took several forms. Most common was probably a tripod with a pulley at its apex and strong flax ropes threaded through it. It was very dangerous work, and the velocity of a heavy stone block when a rope shears is startling.

  For the highly skilled job of building the piers of an archway, the Romans’ lifting technology was simple but ingenious. Once a large stone had been roughed out at the quarry, a mason took a punch and made a hole on each of the opposite sides. They had to be at exactly the same height and width, precisely opposite, otherwise the stone would rise out of balance and could slip. Then pincers, called nippers on British building sites, were held into each hole and the strain taken by men hauling on the pulley rope. The block was slowly hoisted and let gently down onto the cart bed. A centurion will have roared at anyone who slackened his grip too soon and splintered a cart.

  Some examples of a different method of moving stones can still be seen by the observant along the Wall. Using a curved-end chisel, concave triangular holes were made in large blocks, like the basic shape of an isosceles triangle with its apex missing. Masons still use this ancient method and call the cuts Lewis holes. These allowed stones, such as voussoirs, and especially the keystones at the top of arches, to be lifted from their centre. Nippers got in the way of any attempt to slot shaped stones into the semi-circle of an arch. Lewis holes were based on a simple notion. Into the triangular hole a metal grip was inserted. Curved outwards so that its teeth gripped the undercut sides when tension was put on the pulley rope, they were immensely strong and immensely useful. Once a keystone was carefully lowered in, the grip was pulled out easily after the rope had slackened. At that moment the arch was formed and, provided it settled correctly after removal of the semi-circular wooden frame (called a centre) that it was assembled on, the gang moved on to the next milecastle.

  TOOLKIT

  Over 2,000 years, stone has not changed much and neither have the tools used by masons to cut and shape it. The Romans even had saws, although they ran on muscle-power rather than electricity. The ancient iron toolkit fell into two groups. Picks, walling hammers, axes and adzes were used directly on the stone and were preferred by the masons working at the quarries who roughed out what had just been pulled out of the strata. Experienced men take time to look at a stone before they lift up a hammer. Examining the grain, they select a weak point and can often lay open a big boulder with little more than a tap. Several sorts of chisels – claws, bullnoses, gouges, bent chisels, nickers and punches – were in common use for making holes and were all driven by mallets. The wooden version, sometimes called a mel, was used for planing and other less-skilled jobs. Finer judgement needed a metal-headed mallet with most of its weight at the top. These are known as Italian mallets. Working in Greenlaw, the old county town of Berwickshire, Dave Rumbles is a highly skilled mason able to carve lettering in the Roman manner. He works a blank stone with it canted at a 45-degree angle so that the dust and chippings fall away. Loosely gripping an Italian mallet (too tight and tiredness soon sets in with mistakes to follow) and a fine chisel, he can carve at a steady and rhythmic pace, never taking his eyes off the stone.

  Transport logistics were the core of the huge operation begun in AD 122. A four-wheeled ox wagon pulled by as many as ten beasts could haul two tonnes of stone, about seventy normal Wall stones, or four or five pier stones or voussoirs. It has been estimated that an astonishing 30,000 vehicles of one sort or another were used in the three years the Wall probably took to complete. To pull them, around 6,000 oxen were yoked to the heaviest loads. Moving at 3 kilometres an hour, they were slow and ponderous, but steady and not excitable. Horses and mules were much quicker and more nimble-footed, important in difficult country, but had less muscle-power. Nevertheless, it is estimated that the Wall builders used more than 14,000.

  The legions al
ready had many pack-animals to carry their tents and other kit. Mules were generally preferred to horses because they were hardier and needed less fodder. On an x-frame pack-saddle, mules could carry as much as 200 kilograms and they could reach the less accessible areas of the Wall – as could men. It is important not to underestimate the amount carried by legionaries and other labourers. To a considerable extent, Hadrian’s Wall is a monument to human sweat.

  The Romans appear not to have been kind to their pack-animals, driving them beyond what was sensible, as observed in a decree of Constantine Augustus in AD 357: very many persons by means of knotty and stout clubs force the public post animals . . . to use up whatever strength they have. Feed must have been a substantial problem, especially in the difficult central sector of the Wall, and the legionary quartermasters had to have acquired a prodigious supply of hay after the first cut in late June, at the earliest. That implies a great deal of co-operation with native farmers. Twenty thousand draught animals, working hard, will have exhausted the available grazing very quickly.

  The core of the Wall was filled by rubble, clay and soil laid in between two outer skins of masonry. Lime mortar was usually used for bonding, and its production was another major industrial operation. Some kilns for burning limestone already existed. The Vindolanda lists mentioned men sent to the kilns and the need to burn stone. But in 122 many more were urgently required. Always sited close to the limestone quarries, they burned for several days, consuming copious amounts of fuel (in itself another constant need), to produce the powdered lime essential for the masons. Sand was also needed. Mortar was made with one part lime, three parts sand and water. At Fallowfield Fell, near Chesters, a very large sandpit was certainly excavated by the Romans, and there must have been many others.