from the line of the wall, but also from forts in front of it, as at Netherby, or in its rear, as at Lanchester.

At Newstead the three altars of G. ARRIUS DOMITIANUS give him no title higher than that of centurion, nor have we evidence of any other kind that he was set over a garrison of auxiliaries, though instances of such employment of a centurion are known elsewhere. But the mere fact that he appears to have dedicated three altars suggests that he was a personage occupying a position of prominence. That L. MAXIMIVS GAETVLICVS belonged to the Twentieth Legion seems evident from the altar found at Aesica.[1] Of the three representations of the boar, the symbol of the legion, two at least are on heavy stones that must have formed parts of buildings. The fragmentary inscription from the upper level of the pit in the Principia is too incomplete to base theories upon, but it also has evidently dealt with the Twentieth Legion. When we add to the testimony of these stones the indications of change and alteration, gleaned from the foundations of the fort, and confirming what we may learn from history of the short and somewhat insecure hold that the Romans gained in Scotland, it would clearly be unsafe to conclude that the garrison of Newstead was necessarily an auxiliary force. Rather, it appears probable that at one period of its existence the fort had held a contingent, possibly a vexillation, of the Twentieth Legion; but the evidence seems insufficient to enable us to define this period with certainty.

The general plan of the fort suggests that the barracks of the Praetentura were constructed for infantry, and that the Retentura was laid out for the occupation of cavalry, and we might suppose that in its latest period the soldiers of the Twentieth Legion occupied the lines of barrack blocks of the Praetentura, while the horsemen of the Vocontian ala were quartered in the Retentura. When, however, we endeavour to dispose of this force in the buildings discovered, the scheme is not without difficulties. The sixty centuries which composed a legion were grouped in ten cohorts each consisting of three maniples. At Lambaesis three strigae, forming the barracks of a cohort, are to be seen on either side of the Porta Praetoria. The same arrangement existed at Novaesium, and we have a similar disposition of the buildings at Newstead. In both of these larger forts we are dealing with the housing of legionary troops, and we know that the legionary century of the time of Hyginus was composed of

1 We have a parallel instance at Auchendavy on the Antonine vallum where we find four altars dedicated by the centurion M. COCCEIVS FIRMVS of the Second Legion AVGVSTA.

74