THORNY DOORS GAP, WITH NINE NICKS OF THIRLWALL IN THE DISTANCE
It is a whinstone quarry, needless to say, for it is busy cutting a large slice out of the basaltic ridge on which the Wall has clung for so many miles. I had previously been puzzled by the appearance of the Cawfields Quarry, which is quite a landmark for miles, making a rich yellow patch in the landscape. If basalt is a dark blue-grey stone, how can it make a yellow patch? Now was my opportunity to inquire. The manager told me that although whinstone is a dark blue-grey stone, yet it has a yellow "skin" which forms on it under certain conditions, as, for example, when the earth has got in through cracks. It is not a good building-stone, apart from its colour and the difficulty of dressing it, for capillary attraction draws the water up through it very freely, so that it always seems damp. "The Romans were not able to work it, as it can't be worked with wedges."
But somehow they did manage to cut deep ditches through it at the top of Limestone Bank! The great heaps of grey whin-dust (as it is called) lying at the quarry were waiting, I was told, to be made into blocks of artificial stone, being subjected to great pressure, and thus forming an artificial "conglomerate."
Before I left they gave me a practical illustration of how the stone is brought down by blasting.
The Wall continues its course along the fields opposite the quarry, forming a boundary wall between them. It is not in good condition (having so recently tumbled over the cliff, a frivolous person might say!), but its ditch is magnificent, and was full of primroses, very late for the time of year.
The Roman fort of MAGNA is just here, lying to the south of both Wall and Vallum, which now draw near together again, after their long separation. No doubt this fort was originally built by Agricola, long before the Wall was thought of. A recent discovery, given below, goes to prove that.
The site of the fort is to the west of the farm-house of Carvoran. I had no difficulty in tracing the north rampart and the north ditch. The Stanegate came up to the fort, direct from Corstorpitum and Cilurnum; and another Roman road, the Maiden Way, coming from the south, joined it near the south-east angle. The two roads are one as far as Gilsland, where they separate, the former aiming for Carlisle, and the latter for Birdoswald and Bewcastle.
During the recent war, a very interesting bronze vessel was found at Carvoran. "Like a bucket, only the top was where the bottom should be," was the graphic description given me locally, and when I saw the vessel at Chesters Museum, I felt how well it described it. It was a measure for corn, of the time of Domitian, the last emperor under whom Agricola served, but the emperor's name had been erased. It therefore dates from about 82 A.D., but it looks as if it had been made yesterday. The inscription is as clear and clean as ever, except where it has been erased.
"IMP*/*/*/***** CAESARE
AVG · GERMANICO · XV · COS
EXACTVS · AD · S · XVIIS
HABET · P · XXXIIX"