596 
claiming as its head the truly historic city of York, than 
which not even London itself is more famous throughout the 
national annals. 
Isurium, thus bereft of the august patronage and residence 
of Emperors or their Generals, now subsided into a second- 
rate town, but it could not be entirely stripped of importance 
as a good military station upon the great north road. It was 
occupied by a portion of the Sixth Legion, whose head- 
quarters were Eburacum. The remains of temples, a basilica, 
and other public buildings, bear witness to the early develop- 
ment of the place, whilst the numerous well- executed Mosaic 
pavements yet existing testify to the abundance of good 
private dwellings. Other tessellated floors are of plainer 
designs and coarser work, whilst the example before us can 
be classed in neither category. It is a Mosaic of average 
size as to materials, but rudely executed, and for Romano- 
British manufacture, decidedly of late date, and probably 
referable to the end of the third or the beginning of the 
fourth century. Since the publication pf the "Reliquiae 
Insurianse," in 1852, several pavements have been found in 
the city of York and its immediate suburbs, yet the total 
number scarcely amounts to one-half of similar relics found at 
Aldborough. This paucity of known specimens of an im- 
portant and remarkable class of remains at Eburacum has 
been much dilated upon, and I am disposed to regard it as 
arising from the great depth at which such lie, rather than 
to their absence from the buildings of the Roman city. The 
slow but certain rise of the ground-level of large towns and 
cities is a very remarkable feature, but rarely chronicled; 
with the exception of London probably no place in the 
kingdom exhibits a greater heightening of the surface level- 
than York, where the foundations of the earlier Roman 
buildings are laid upon virgin soil from sixteen to eighteen 
feet below the present pavements of the streets. Consequently 
