Page:Roman Manchester (1900) by Charles Roeder.djvu/35

Rh The construction of the northern defences, I need scarcely remark, differs entirely from what we see at Wilderspool (Veratinum) and Ribchester (Bremetonacum). We must again remember that the ground on the northern side consisted of marsh, low swamp, and undulating gravel ridges, which would offer natural advantages in the adoption of this parallel work.

A similar arrangement is observed in the Roman station at Birrens, in Annandale (4 acres in extent), where on the north-east side we have also a series of parallel trenches, "thus establishing a resemblance between this work and the stations of the German limes not yet proved in any other Roman or native work in Britain." At Birrens we find six ditches bending round the angles without coalescing.

At the edge of the marshy depression, inside the new police station, a little black pit was discovered. A few yards away from it in situ on the river gravel I found a corroded brass coin, which Mr. Robert Blair refers to Antoninus Pius (138-161). Now above this gravel we have in succession a stratum of Roman soil, about 22 inches thick, abounding in ornamental Samian ware, typical, according to Professor Haverfield, who examined these finds, of the second century; then upwards a gravel road, 3 inches deep, and on the top of it again 19 inches of Roman soil with quantities of Roman pottery in it.

This part of the section then, as I read it, seems to mark four distinct phases: (1) The undisturbed Roman period, when the ground was still mere marsh and bog; (2) conversion into fosses; (3) the filling up of the fosses