The later of the two gates on the south seem to have been constructed on the lines of those of Castlecary. There was the same return of the ends of the wall, but nothing definite could be ascertained as to the precise position of the gate or the guard chambers. Close to this entrance there were found two sandstone blocks, one on either side, each having a circular depression cut in it at one end. They had evidently been used as pivot stones. The larger of the two was twenty and a half inches long, sixteen inches broad, and eight and a half inches thick. In one of them a harder river-stone had been fixed in the pivot hole, probably to enable it to withstand the wear and tear better. The west gate showed a little more detail; the actual opening was twelve feet wide, and the line of the cobbled roadway, slightly raised in the centre, was quite distinct. On the south side the wall had evidently returned almost at right angles, although only the cobbles of its foundation remained. It had projected four feet in advance of the corresponding wall on the north side of the gate, which was faced with a single course of sandstone blocks and curved inwards.
A rather more definite impression was gained of the east gate of the fort and also of the gate in the reducing wall, albeit not a single stone of the masonry of either had survived. In the latter case the stonework must have been removed when the defences were once again enlarged, for the later road passed over the undisturbed cobble foundation of the disused gateway. It was quite plain that it had been of the type common in the Limes forts. The opening was nine feet wide. On either side had stood a guard-house, which had projected three feet in front of the wall. On the exposed side, the foundations of these guard-houses were nine feet in thickness, indicating walls of at least eight feet. On the sides next the gate they were thinner,—not more than six feet,—while at the back and on the sides that abutted on the reducing wall, they were only three and a half feet thick. Each contained a small chamber eight and a half feet by six feet. The width of the entrance justifies us in inferring that the door was only single, not double. The east gate had the same character. There the outline of the guard-houses could be made out, the floors showing traces of charcoal some fifteen inches below the surface. But here also every fragment of masonry had disappeared, while the cobbles from the road and from the destroyed walls had been thrown out in a confusion which made it difficult to obtain exact measurements.
The Fort as it originally appeared
The mere details of foundations and the dimensions of these long filled
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