i9i4" I 9 I 5-] Hadrians Wall. 143 



covicus a cartload of coal was excavated. The Eomans 

 worked the coalfields of England, as, in fact, they extracted 

 everything else of value to the best of their ability. But the 

 guard chambers tell of many things not so easily discovered 

 from other sources. They tell us that, massive as are these 

 defences, they have yet not once nor twice proved too weak 

 to keep out the northern foe. In clearing out certain of them, 

 a floor has been found which, from external levels and other 

 appearances, is quite obviously not the original floor of the 

 building, and on this upper floor being carefully removed the 

 excavators have come upon a deep layer of wood ashes and of 

 broken and fire-blackened masonry. Again beneath this has 

 been found the original floor of the building, proving that the 

 place had been sacked and burned, and that, on subsequent 

 recovery and reoccupation, the Eomans, instead of clearing 

 out the rubbish, have simply levelled it and laid a new floor 

 on the top of it. When we examine the gateways we find 

 a similar condition. Some of them show as many as three 

 successive alterations. This is well shown in the western 

 gateway at Aesica. On the ground -level was the original 

 entrance, and it has been of the most massive description. 

 The pivot hole of one of the gates can still be seen showing 

 evidence of much use. At a later date there occurred partial 

 destruction of the defences, as the ashes and ruins in the 

 guard chamber show. On reoccupation and repair, a new 

 level for the gateway was selected, two feet higher up, shown 

 by the pivot-hole of the second gate ; but after a further 

 lapse of time another change took place, and the gateway 

 was completely built up with a solid mass of rubble masonry, 

 but neither of the two later modifications is comparable in 

 workmanship with the first, and that is what we find all 

 along the wall. Later work is bad. This blocking up of the 

 gateways can be traced in all the stations which have been 

 excavated — sometimes one -half, sometimes the whole. The 

 east, west, and south gateways at Cilurnum were all thus 

 built up. The west gateway at Borcovicus was completely 

 blocked up, but the stones were removed by the excavators 

 in order to examine the details of the original work. Of 

 course the explanation of this is that, towards the close of the 

 Eoman occupation, Britain was being continually drained of 

 VOL. VII. K 



