As might be anticipated, the specimens of towers which furnish the most apposite illustrations are found in the Border Counties, and in the Welsh Marches, or, on the other hand, in those districts which have few natural defences. Beginning with Cumberland, we have the embattled tower of Great Salkeld church, guarded by a massive door, plated with iron, and fitted on the inside with stout iron bars. Under the aisle of the church are chambers, which are believed to have been used as dungeons[274]. The tower at Burgh-on-the-Sands, near Carlisle, seems to have served as a fortress or pele-tower[275]. (Etymologically _pele_ or _peel_ = the _stockaded_ enclosure or fort.) Normally, the pele or “peel” towers were special structures, and were erected along the border irrespective of the position of churches, as at Corbridge, in Northumberland[276]. Nevertheless, there is little doubt that strong church towers were used as substitutes for peles in times of necessity. Thus, the twelfth century tower of Edlingham church, in Northumberland, is one of several that served this purpose; while Merrington church, with its tall steeple, crowning an eminence, actually stood a siege. The tower of Bedale church, near Richmond in Yorkshire, seems to have been constructed purposely for defence. The narrow staircase has, in fact, a portcullis groove, which was accidentally revealed after the steeple had been struck by lightning. The portcullis screened the tower from the body of the church[277]. Melsonby tower, also in Yorkshire, has been described as “a Norman keep in miniature[278].” The round steeple of the Early Decorated church of Roos, in Holderness, is supposed to have been a post for watch-and-ward. It stands on high ground, and contains, near the top, a chamber which is reached by a spiral staircase of stone[279]. We know that the surrounding district was terribly ravaged by the Danes, and it is interesting to note that, in 1836, there was discovered, in a ditch at Roos, a rude model of a boat with a warrior crew. This curious object is considered to be of Scandinavian origin, and to date back to the invasion of the Danes and vikings[280]. If it be urged that the church fabric belongs to a period long subsequent to the raids of the Northmen, the comment is both fair and relevant. Two replies might be made: first, analogy indicates that churches of this kind most likely had predecessors on the same site, and secondly, defensive structures continued to be built long after the events which called them into existence passed away.