The Wall
Page 20
Mortar was almost certainly mixed off-site, probably near the lime kilns, and then taken up to the Wall wet. Logistically very complex – and dangerous – this sort of awkward transfer had to be managed many times, even in very rough country. The problem was that the powdered lime is so acidic that it burns badly to the touch, lifting off skin in a moment. Loading needed tremendous care, especially when it was windy, and if any spilled during carriage then a pack-animal would have been seriously injured. Sand and lime were carefully turned and folded in volcano-like cones as water was added in stages (just as it is now by those without a mechanical mixer). Then the mixture was loaded into panniers slung on pack-saddles, and the mules were carefully led up to the building site. The mortar beds which can still be seen on the Wall are generally not thickly laid, unlike modern compo. This required real skill to keep the beds level and the outer face flush.
SOLDIERS AND SAILORS
Everybody who was at hand helped to build the Wall. Even the sailors of the British fleet were press-ganged into service. Tile-stamps, inscriptions and other scraps of evidence indicate that they were certainly at work at the eastern end. It may be that they organised and piloted barge traffic up the Tyne, much the best way to carry bulky and heavy building materials. But they will not have been Jolly Jack Tars giving their landlubber comrades a hand. The Classis Britannica contained many men who were as much soldiers as sailors, equipped more like modern marines. And they could have possessed many of the building skills needed to work just as effectively on land.
As the milecastles, turrets and the Wall itself rose ever higher, another element of planning came into play. The finished Wall was probably about four metres in height and, to lay the top courses of stone and fill in the core, scaffolding was needed. Even higher scaffolds were required at the milecastles and turrets. At any given time during the building season (this lasted about thirty-five weeks – working in the winter weather involved disabling difficulties) each legion had approximately five work-gangs taking the Wall to its full elevation, four specialist groups working at the milecastles and two completing the turrets. All of them needed scaffolding. Experts have reckoned that 150,000 metres of straight wooden poles were cut to provide it. This meant a massive sourcing and felling operation in AD 122 and 123.
Putlog holes, where scaffolding was wedged into existing courses of stonework for stability, have been found along the Wall, but it is likely that most frameworks were free-standing. This saved on wood, and the frameworks were easier to move on. Straight-sawn timber is a relatively modern invention, and the irregularities of natural tree growth will have made for some rickety and dangerous structures. Lifting up heavy Wall stones off a scaffold in a high wind was not something many men will have volunteered for.
Progress is likely to have been rapid, especially when the Emperor and his Governor were riding back and forth along the line. It is thought that Hadrian stayed in the north-east for three months, probably lodging at Vindolanda for part of the time. Nevertheless the whole area must have looked like a gigantic building site for a long time. At Highshields Crag, just to the north of Vindolanda, there is evidence to show that, after the foundations were dug, no further work took place for a long enough time to allow soil to blow over the site and cover it. Birdoswald Fort was begun and then abandoned. Scrub grew up inside the half-built walls and had to be burned off before work could resume.
Inscriptions allow some secure dating for the construction of Hadrian’s Wall. In addition to that of the Emperor, the name of Aulus Platorius Nepos is found in several places. And since no other Governor is commemorated anywhere, it seems likely that the project was completed, with some omissions, during his tenure of office. Nepos probably left Britannia in 125, 126 at the latest.
That end date was only made possible because the scale of what he and Hadrian had planned was reduced, almost at the outset. The original Wall foundations were nearly 3 metres in width and probably calculated to carry a very high and impressive superstructure. This was quickly modified and a new width of 2.1 metres specified. Along much of the line the masonry is offset at the bottom courses where the narrower wall sits on top of broad foundations. This was almost certainly done to save time and materials.
THE NAMES OF THE FORTS
If Ravenglass is included, and the forts that were off the line of the Wall, like Vindolanda, are not, what follows is a list of the names given to the Wall forts, with their meanings. Most are Celtic; there are only two in Latin:
Wallsend – Segedunum – The Strong Fort
Newcastle – Pons Aelius – Hadrian’s Bridge
Benwell – Condercum – Viewpoint Fort
Rudchester – Vindobala – White Peak Fort
Halton Chesters – Onnum – Waterfort
Chesters – Cilurnum – Riverpoolfort
Carrawburgh – Brocolitia – Heatherfort
Housesteads – Vercovicium – The Fort of the Good Fighters
Great Chesters – Aesica – Fort of the God
Carvoran – Magnis – Rockfort
Birdoswald – Banna – Promontory Fort
Castlesteads – Camboglanna – Fort on the Curved Bank
Stanwix – Uxelodunum – Highfort
Burgh-by-Sands – Aballava – Appletreefort
Drumburgh – Concavata – Hollow Fort (Latin)
Bowness-on-Solway – Maia – Greatfort
Beckfoot – Bibra – Beaver Fort
Maryport – Alauna – Rockyriverfort
Burrow Walls – Magis – Plainsfort
Moresby – Gabrosentum – Goatspathfort
Ravenglass – Glannoventa – Beachmarketfort
There was much more to Hadrian’s Wall than just a wall. After it was more or less complete, work-gangs began to dig a defensive ditch on the north side. It was deep and wide. At a depth of 2.5 to 3 metres with 33 per cent sloping sides, the ditch presented a real barrier and, because the whole excavated area was between 9 and 12 metres wide, it could not easily be bridged. The spoil was piled up on the north side to make the ditch seem even deeper, and it was probably revetted with the turf removed at the beginning of building work. Roman soldiers were used to ditch-digging; they did it routinely while overnighting on campaign. And it was thought to be a vital skill. The great first century AD general Domitius Corbulo once remarked that the pick was the weapon with which to defeat the enemy. The dolabra, an entrenching tool carried by legionaries, no doubt swung hard and often on the northern flank of Hadrian’s Wall, but the work was unusually difficult. When modern-day volunteers at Vindolanda imitated the work done between 122 and 126, they found ditch-digging much harder than wall-building.
The reason for this was not only to be found in differences in fitness and toughness; it also related to the nature of the ground. At Limestone Corner the hard rock immediately in front of the Wall simply could not be removed to make a clean ditch, and the vain efforts of the soldiers can still be seen. One huge boulder still carries the slots cut into it for wedges. These were no doubt hit hard with bursting hammers under the critical eye of a centurion, but the great boulder would not split and had to be left where it was: a monument to Roman frustration.
Limestone Corner was not unusual in presenting difficulties. Much of the ditch had to be dug out of clay deposits and this was what exhausted the modern-day Vindolanda diggers. When dry the clay was almost rock-hard and when wet it turned to putty, sticking to the blades of shovels and very heavy to lift. When it rained, as it will have done often on the work-gangs at the Wall, the ditch simply filled up, did not drain and had to be bailed before any more excavation could be done. Then there was the problem of spoil removal. In such a deep and wide ditch, triple shovelling was necessary as it got near the required depth. One labourer at the bottom hacked out as much spoil as they could lift, brought it up to shoulder height and deposited it about halfway up the slope. Then a second person picked it up and lifted it to the top. There a third mounded the spoil on the northern bank and smo
othed it off. If baskets or stretchers were used, the work might have been easier, but much slower.
More satisfying than all that slog must have been the building of the Wall’s four bridges across the Tyne, the North Tyne, the Irthing and the Eden. For it seems that they were things of beauty. All are long gone now, but traces of the bridge at Chesters, where the Wall crossed the North Tyne, are eloquent. Probably one of the earliest structures to be completed, it was carried on eight hexagonal piers which supported small arches of about 4 metres in width. Cutwaters divided the current of the river and, for symmetry and strength, they seem to have been built both upstream and downstream.
DAM DIFFICULT
Like Trajan’s great bridge over the Danube, all of the four Wall bridges were built with the same basic technique. A cofferdam was driven into the river-bed where each of the stone piers was designed to sit. The most difficult of the four would have been the Pons Aelius. The Gateshead Gorge canalised the sprawling Tyne into a strong current between two areas of high ground. In essence a cofferdam was a watertight box constructed from piles banged into the river-bed. Always larger than any of the bridge’s piers, its purpose was to expose the bed so that it could be built on. Iron-tipped oak piles were first hammered in by a pile-driver lashed to a barge anchored at the site. This was a large and heavy stone hoisted by block and tackle on a frame and then dropped. It must often have hit the pile off-centre. Once an oblong had been completed, engineers set to, driving in an inner skin of more piles and then gradually sealing the joins with clay. Using a waterscrew (invented by Archimedes of Syracuse) turned from barges, or from the banks if the river was not wide, water was lifted out. On the North Tyne and certainly on the Irthing, it would have been possible to bail each cofferdam with large buckets and a hoist. When the river-bed was at last exposed, tar-covered piles were hammered into it and building began on top of them. Pre-cut stone was laid with a rubble core and bound together with pozzolana cement. Roman bridges were famously elegant.
Although it made no sense to carry the Wall across a bridge, it seems that the Romans did exactly that. The platform was the same width as the broad wall foundations – and what does make sense is a walkway from one bank to the other. Perhaps there was a boom chain suspended above the water level to inhibit those who fancied rowing under the Emperor’s Wall. In 207 to 208, the Hadrianic bridge was replaced by a grander three-arched version, which had impressive two-storey abutments at either end.
Cawfields milecastle lies near the western edge of the Whin Sill, not far from where the Wall drops down to Greenhead. In a good state of preservation, it is much visited – and marvelled at by some. Like the entire Wall, it displays a certain bloody-mindedness, even an unbending rigidity of thought. Up on the Sill, Cawfields commands long views to the north, but the gate on that side opens onto a sheer drop. Only 30 metres to the west is a much better and flatter site, one of the nicks in the Whin Sill (the route taken by visitors), and it would have allowed access through both of the milecastle’s gates. But the milecastle had to be a mile, exactly a mile, from the next one, so that was where it had to go.
The first phase of building work showed much more general inflexibility. When the Wall was connected to its turrets and milecastles, it restricted Roman as well as native freedom of movement. The garrison was initially very small, on paper only 1,000 to 1,500 men and, if the Tungrian strength report from Vindolanda is any guide, probably many fewer in practice. All that these men could do was observe and patrol. A much larger concentration of troops was stationed at each of the forts along the Stanegate Road, sometimes 2 or 3 kilometres south of the Wall. If an emergency sparked, they had some distance to go to deal with it. And when detachments of soldiers reached a milecastle, they could only funnel through its gates slowly. It was all very unsatisfactory. Roman armies always instinctively sought the open ground and – perversely – their own Wall was preventing them from reaching it quickly.
ROMAN WALL BLUES
Service in the frontier garrison may have had its bleak moments, but it surely cannot have been as bad as it was painted by W.H. Auden in ‘Roman Wall Blues’:
Over the heather the wet wind blows,
I’ve lice in my tunic and a cold in my nose.
The rain comes pattering out of the sky,
I’m a Wall soldier, I don’t know why.
The mist creeps over the hard grey stone,
my girl’s in Tungria; I sleep alone.
When I’m a veteran with only one eye
I shall do nothing but look at the sky.
(from W.H. Auden. Collected Poems, Faber and Faber)
GARRISONS
Many languages were heard along the Wall in the 120s. Forts were garrisoned from all over the Empire, from Spain, France, Belgium, Holland, Switzerland, Syria, Hungary, Greece, Romania and Germany. Troop dispositions are also informative. They show where the Romans expected trouble and what kind. Inscriptions are handy guides to who was where – but there are still some question marks along the line:
Wallsend
Cohors quingenaria equitata [?]
Benwell
Ala quingenaria [?]
Rudchester
Cohors quingenaria equitata
Halton Chesters
Cohors quingenaria equitata
Chesters
Ala Augusta ob virtutem appellata
Carrawburgh
Cohors quingenaria equitata
Housesteads
Cohors milliaria peditata
Great Chesters
Cohors VI Nerviorum quingenaria peditata [?]
Carvoran
Cohors I Hamiorum quingenaria peditata
Birdoswald
Cohors I Tungrorum milliaria peditata
Castlesteads
Cohors quingenaria peditata
Stanwix
Ala Petriana milliaria
Burgh-by-Sands
Cohors quingenaria equitata [?]
Drumburgh
[?]
Bowness-on-Solway
Cohors milliaria equitata
Beckfoot
Cohors quingenaria peditata
Maryport
Cohors I Hispanorum milliaria equitata
Moresby
Cohors quingenaria equitata [?]
Not long after work began in 122, a decision was taken to move forts up to the line of the Wall. And, so that access to the north, the likely source of most trouble, could be much more immediate, gates were sited beyond the Wall line. At Chesters, where a cavalry regiment was based, three of the four fort gates allowed troopers to ride directly out, without having to pass through the Wall. The original plan was a monumental mistake, producing the obvious effect of penning in the garrisons, but the decision to change appears to have been taken quickly.
One of the results of this early blunder and its remedy is spectacular. Housesteads is probably the most beautifully situated of all the Wall’s forts, and because of its location in the central sector, remote until the road-building of the mid eighteenth century, it has survived remarkably. The Border Reivers also helped preserve the old Roman fort during the fourteenth to sixteenth centuries. Using the ready-made cut stone which lay everywhere to hand, they built a longhouse and at least two bastle houses on the site. These were heavily defended, thick-walled structures designed to frustrate rather than repel attackers. The remains of one can clearly be seen outside the southern gate at Housesteads. A ground floor, or pend, was built without windows and it was intended to keep safe a farmer’s beasts during a raid. They were driven in, packed tight, bellowing with fear, and the stout door barred shut from the inside. In the roof of the pend there was sometimes a trapdoor to the first floor. This was more easily and more usually accessed by an outside stair or ladder, and out of its tiny windows defenders hurled abuse and anything else they could find at the horsemen circling below. Bastle houses were primitive but effective, a poor man’s peel tower. To the Armstrongs of Gandy’s Knowe, a branch of one of the
most notorious of all the reiving surnames, the irony of rebuilding a much lesser defensive structure on the fringe of one so sophisticated might not have been lost. They were ferocious, ruthless thieves, but not usually ignorant. The perimeter of the fort itself was probably barricaded into use as a cattle corral, often somebody else’s cattle, as the Armstrongs rode the moonlight and raided in the Tyne Valley and to the north.
At the time of the Border Reivers, William Camden compiled his great antiquarian history Britannia (published in 1586). He rode along the line of the Wall, a countryside he thought lean, hungry and waste. Hadrian’s Wall amazed him: Verily I have seen the tract of it over the high pitches and steep descent of hills, wonderfully rising and falling. Camden knew of Housesteads Fort, understood that there was much to see but, to his intense frustration, he could not get near it: I could not safely take the full survey of it for the rank robbers thereabouts. Bandit country.
Considering how the climate had hardened the carcases of Borderers, he observed how the descendants of the horsemen in the Vindolanda letters lived:
In the wastes . . . you may see it as were the ancient nomads, a martial kind of men who, from the month of April into August, lie out scattering and summering with their cattle, in little cottages here and there, which they call shiels and shielings.