CHAP. IV. OF ANCIENT BUILDINGS. 217 



beneath the pavement of the enlarged room. 

 Mr. Joyce believes that this buried wall must 

 have been built before the reign of Claudius II., 

 who died 270 A.D. We see in the accom- 

 panying section, Fig. 15, that the tesselated 

 pavement has subsided to a less degree over the 

 buried wall than elsewhere ; so that a slight 

 convexity or protuberance here stretched in a 

 straight line across the room. This led to 

 a hole being dug, and the buried wall was 

 thus discovered. 



We see in these three sections, and in 

 several others not given, that the old pave- 

 ments have sunk or sagged considerably. 

 Mr. Joyce formerly attributed this sinking 

 solely to the slow settling of the ground. 

 That there has been some settling is highly 

 probable, and it may be seen in Fig. 15 

 that the pavement for a width of 5 feet 

 over the southern enlargement of the 

 room, which must have been built on fresh 

 ground, has sunk a little more than on the 

 old northern side. But this sinking may 

 possibly have had no connection with the 

 enlargement of the room; for in Fig. 13 

 one half of the pavement has subsided more 



