Of this strategic movement several strong indications remain upon the face of the district; which it is thought, mutually derive increased force from their accumulation. One of them is the existence, at the outposts of this expedition, of two of Æthelbald’s favourite dedications of his kinswoman. One, at Warbstow, stands at the western extremity of an incroachment of about eight miles beyond the Tamar, near Launceston, into Cornwall--still visible in our county maps, in the abstraction of an entire parish from the western side of the otherwise frontier river, by an abnormal projection beyond it. The other is at Wembury, where the church is finely situated on the sea-cliff of the eastern lip of Plymouth Sound. These two examples of the dedication, which was the favourite stamp of the conqueror’s heel, mark therefore the western and southern extremities of the assumed invasion.
Another trace of this great unwritten Mercian descent upon Damnonia, may be discerned in the structure, as well as the constituents, of the place-names that cover the invaded district. The country, between the central highlands of Devon and the north-west coast of Devon and north-east of Cornwall, is not only secluded into an angular area bounded by the sea; but lies quite out of the course of the torrent of West Saxon advance westward: which indeed had been evidently checked by the Dartmoor heights. It might have been expected, therefore, except for the explanation now offered, that this district would have retained a strong tincture of its original Celtic condition, in that lasting index of race-occupancy its place-names. In this respect it might have presented the appearance of having been conquered, but not of a complete replacement of population. On the contrary, at the first glance of a full-named map, or in a passage through it, the entire district is surprisingly English. Besides this, the place-names have not only conspicuous peculiarities of structure, that at once distinguish this district from that of the West Saxons south and east of Dartmoor; but these recur with such uncommon frequency and uniformity, stopped by almost arbitrary limits, as to be manifestly due to a simultaneous descent of a very large population, at once spreading themselves over the whole of an extensive region.