Our course hitherto has been a detail of facts; now we enter upon the region of speculation. In the former Parts of this work, the history of the Roman occupation of Britain has been briefly told and an attempt made to depict the present condition of the Vallum and Wall, with their camps, castles, and outworks; now the question must be put—Is the Barrier the Work of one master-mind, or are its several parts the productions of different periods, and of different persons? Had the statements of the ancient historians upon the subject been explicit and consistent, the inquiry would involve simply an appeal to their authority; unhappily, the information which they afford is not only very meagre, but of a character so unsatisfactory, as to compel us to sift their evidence, and to compare it with the facts which we glean from an examination of the fortifications themselves.
AGRICOLA’S WORKS.
Agricola, we are informed by Tacitus, erected forts both on the Lower and Upper Isthmus; we are nowhere told that he drew walls, whether of earth or stone, across either of them. The northern rampart of the Vallum has by many been conceived to be the work of Agricola. In the absence of any direct historical testimony bearing upon this subject, the circumstance that the lines of the Vallum pursue a course precisely parallel to each other, must be considered as fatal to this theory. It is altogether incredible, that two engineers should at different periods construct independent works, without crossing each other’s ramparts. In Roy’s Military Antiquities, several instances are given where the trenches of one encampment cut arbitrarily those of another, the troops who last occupied the post, not seeming to pay the least attention to the works of their predecessors; the lines of the Vallum would doubtless exhibit the same appearance had they been the works of different periods. The claims of Agricola to the authorship of any part of the Vallum may therefore at once be set aside, and the inquiry be confined to the relative claims of Hadrian and Severus.
HADRIAN AND SEVERUS.
If the parallelism of the lines of the Vallum be fatal to the theory, that one of the mounds is the work of Agricola, and the others the work of Hadrian, a similar mode of reasoning leads to the conclusion, that the Vallum and the Wall cannot be independent structures. If Severus, finding that the earth-works of Hadrian had fallen into decay, or were no longer sufficient to wall out the Caledonians, had determined to erect a more formidable Barrier, would he not have mapped out its track without any reference to the former ruinous and inefficient erection? Had he done so, we should find the lines taking independent courses—sometimes contiguous, occasionally crossing each other; sometimes widely separated, seldom pursuing for any distance a parallel course, but the Wall, as the latest built, uniformly seizing the strongest points, whether previously occupied by the Vallum or not. This, however, is not the case; the Wall and Vallum, in crossing the island, pursue precisely the same track from sea to sea; for the most part they are in close companionship, and in no instance does the Wall cut in upon the trenches of the Vallum. At the first view of the subject, therefore, we should be disposed to question the accuracy of the opinion which gives to these works distinct dates, and ascribes the Vallum to Hadrian, and the stone Wall to Severus. Before further prosecuting this inquiry, it will be well to lay before the reader all the statements of the ancient historians upon the matter in question; he will by this means see the necessity of appealing to the structures themselves for a satisfactory decision of the question.
TESTIMONY OF HISTORIANS.
Herodian was contemporary with Severus, and professes to have been an eye-witness of all that he relates. He gives a detailed account of the emperor’s proceedings in Britain, but does not once mention the Wall. Dion Cassius was also contemporary with Severus. As before observed, that part of the original work which treats of Britain is lost; we have, however, Xiphiline’s abridgment of it. The only reference which he makes to the Wall, comports with its existence previous to the arrival of Severus in Britain, Speaking of that emperor’s expedition against the Caledonians, he says—
Nor did he ever return from this expedition, but died three years after he first set out from Rome. He got a prodigious mass of riches in Britain. The two most considerable bodies of people in that island, and to which almost all the rest relate, are the Caledonians and the Meatæ. The latter dwell near the Barrier Wall (οιχουσι δε οἱ μεν Μαιαται προς αυτῳ τῳ διατειχισματι, ὁ την νῆσον διχῆ τεμνει) which divides the island into two parts.
Spartian, writing about A.D. 280, is the first person who gives us any direct information about the erection of a Wall; and it is on his testimony chiefly that the credit of the work has been given to Severus. Speaking of Hadrian, he says—