F. 5.—­Quite possibly all are in measure true.  The “Vallum” as we now see it is obviously meant for defence against a southern foe.  But the spade has given abundant evidence that the rampart has been altered, and that, in many places at least, it at one time faced northwards.  Though not an entirely satisfactory solution of the problem, the following sequence of events would seem, on the whole, best to explain the phenomena with which we are confronted.  Originally a British earthwork[290] defending the Brigantes against the cattle-lifting raids of their restless northern neighbours, the “Vallum” was adapted[291] for like purposes by the Romans, and that more than once.  After being thus utilized, first, perhaps, by Agricola, and afterwards by Hadrian (for the protection of his working-parties engaged in quarrying stone for the outer fortifications), it became useless when the Wall was finally completed,[292] and remained a mere unfortified mound so long as the Roman power in Southern Britain continued undisturbed.

But when the garrison of the Wall became liable to attacks from the rear, the “Vallum” was once more repaired, very probably by Theodosius,[293] and this time with a ditch to the south, to enable the soldiers to meet, if needful, a simultaneous assault of Picts in front and Scots[294] or Saxons behind.  Weak though it was as compared to the Wall, it would still take a good deal of storming, if stoutly held, and would effectually guard against any mere raid both the small parties marching along the Military Way[295] from post to post, and the cattle grazing along the rich meadows which frequently lie between the two lines of fortification.

F.6.—­As we have said, the line of country thus occupied teems with relics of the occupation.  Coins by the thousand, ornaments, fragments of statuary, inscriptions to the Emperors, to the old Roman gods, to the strange Pantheistic syncretisms of the later Mithraism[296], to unknown (perhaps local) deities such as Coventina, records of this, that, and the other body of troops in the garrison, personal dedications and memorials—­all have been found, and are still constantly being found, in rich abundance.  Of the whole number of Romano-British inscriptions known, nearly half belong to the Wall.[297]

F.7.—­As an example of these inscriptions we may give one discovered at Caervoran (the Roman Magna), and now in the Newcastle Antiquarian Museum,[298] the interpretation of which has been a matter of considerable discussion amongst antiquaries.  It is written in letters of the 3rd century and runs as follows:—­

    IMMINET .  LEONIVIRGO .  CAELES TI .  SITV SPICIFERA .  IVSTI .  IN
    VENTRIXVRBIVM .  CONDITRIX EXQVISMVNERIBVS .  NOSSECON

    TIGITDEOS .  ERGOEADEMMATERDIVVM PAX .  VIRTVS .  CERES .  DEA . 
    SYRIA LANCEVITAMETIVRAPENSITANS IN .  CAELOVISVMSYRIASIDVSEDI
    DIT .  LIBYAE .  COLENDVMINDE CVNCTIDIDICIMVS
    ITAINTELLEXITNVMINEINDVCTVS TVO .  MARCVSCAECILIVSDO NATIANVS . 
    MILITANS .  TRIBVNVS INPRAEFECTODONO .  PRINCIPIS.