THE ROMAN WALL. I07 



the remains of the ditch are specially distinct) it had the protec- 

 tion of the loch or swamp formed by the Allander. Going east 

 for many miles the Kelvin valley afforded a similar protection to 

 the north. Let the hand of man be removed, let the drains get 

 choked, the river embankments be destroyed, and the spoil of a 

 virgin forest be brought down by every flood to block the river, 

 and in a very few years the Kelvin would forsake its present 

 channel and the haughs of Balmore would be a swamp. In the 

 six miles from Killermont to Kirkintilloch the country is almost 

 level, having a fall of only five or six feet. 



There can be little doubt that this was the state of the district 

 in Roman times, and it explains the curious break in the wall 

 where it is lost at Temple of Boclair till it is found again at Bal- 

 muildy, fully a mile straight south from the former point. The 

 object was to keep, as far as possible, on the higher grounds over- 

 looking the Allander and Kelvin morasses, and to cross the latter 

 at its narrowest point. 



Strong as the wall was, it did not fulfil the purpose for which it 

 was constructed. We read of irruptions of the natives in 162 and 

 182, when they broke through the defence and overran the 

 district between the walls. In 208 so serious was the state of 

 matters that the Emperor Severus led a large army in person right 

 to the extremity of the islands. The natives did not meet him on 

 the open field, but kept up a harassing attack among the woods 

 and hills. Although he did not fight a single battle he is said to 

 have lost 50,000 men by these attacks and by the hardships of the 

 march. He reconstructed the wall between the firths, which from 

 this fact is sometimes called Severus' wall. The Caledonians 

 sued for treaties of peace, but within a year they broke them 

 while Severus was still at York on his way to Rome. He swore 

 he would exterminate the rebels, but death prevented him carry- 

 ing out his threats. 



Little is known of the next hundred years, but the Picts and 

 Caledonians from the north, joined with the Scots from Ireland, 

 continued to prey upon the provincials during the third and 

 fourth centuries. An able general at the head of a legion or two 

 would drive them beyond the wall, but when he withdrew they 

 quickly returned to the attack. In the end Rome, about 407, 

 wearied and weakened by these incessant irruptions which she 



