Prehistoric Archaeology of Cambridgeshire 239 



counties, and elsewhere by arbitrary lines the exact delimi- 

 tation of which was due, doubtless, to long-forgotten local 

 reasons of the tenth century. Its greatest length from north 

 to south is fifty miles, ife greatest breadth about twenty-five, 

 either line of greatest dimension passing through the town of 

 Cambridge. 



"The county is divided by Nature into two regions of 

 about equal size, but very different in character, the fenlands 

 in the north and the low chalk uplands in the south. The 

 latter, strictly speaking, form the actual shire of Cambridge, 

 the former having to a great extent a legally independent 

 recognition, under the name of the Isle of Ely.... The region 

 thus privileged is now a vast alluvial plain, almost treeless, 

 intersected in every direction by a net- work of ditches, locally 

 called 'lodes,' from which the water is pumped by steam 

 power into the sluggish channels along which it makes its way 

 to the sea. The whole district is only kept dry by artificial 

 means, for it is well below r sea-level, and even within living 

 memory was one vast morass, tenanted by innumerable wild- 

 fowl. To this day it remains sparsely inhabited, the few 

 towns and villages located on the almost imperceptible rises, 

 marking what were once islets amid the marsh. The elevated 

 ground on which Ely itself stands formed an isknd of greater 

 height and of respectable size, giving space for a whole group 

 of villages. It is still surrounded by water, various branches 

 of the Ouse stagnating around it. 



"The Southern region consists of low chalky uplands, 

 through which the Cam and its sister stream, the Granta, 

 with their various tributaries, have eroded marvellously broad 

 valleys for such petty rivers. The former (also called the 

 Rhee) has its source in a lovely group of springs called 

 Ashwell, in Hertfordshire, just across the county boundary; 

 while the latter in like manner rises just outside the county 

 near Saffron Walden in Essex. The southern boundary of 

 their basin is formed by the escarpment of the great chalk 

 plateau which sweeps through England from the Yorkshire 



