built together seventy-one passus of the compass of the walls, and the general work was probably directed by an officer of the Twentieth Legion, of which a tile was discovered. These troops were all detailed from the headquarters of the chief station at Chester.
Later on we meet with tiles of the Third Cohort of the Bracaræ and an altar of the Præp. Vex. Raet. et Noric. and another erected by an officer of the sixth legion, all of which point to York and the northern Roman Wall, and tending to the conclusion that in the following century it was garrisoned not from Chester, but by troops stationed in the north. It is, of course, impossible to define the strength of men by which the station was held. It was never anything but a small third-rate castrum and similar in size (5 acres) to the forts along Hadrian's wall, which may have held each a complete cohort or ala of nominally one thousand or five hundred men (in some cases certainly one thousand).
The formation of the suburbs probably began in the second century, for most of the earliest ornamental Samian pottery scattered over its area, as between Bridge Street and Camp Street, and Gaythorn, Knot Mill, and Hulme, consists of specimens characteristic of types of the second and third century. Of the pottery inside the station nothing can be said, as a systematic search there has never been made. In order to realise the appearance of Castlefield Station and its immediate vicinity at that epoch we must keep before us the fact that the whole district in subsequent times has been more or less levelled and artificially covered by 4 feet to 5 feet of soil and rubbish. In its original state the surface was very uneven and its undulating character gave rise to a succession of little hillocks, valleys, and hollows, abounding with pools, springs, and rills. The white valley-gravel skirted the
