8 The Physiography of Cambridgeshire 



irregular ridges protruding from the edges of the Fen. They 

 consist chiefly of fragments of flint. 



In the neighbourhood of Fordham, Chippenham, and New- 

 market a sheet of gravel of uncertain origin caps a plateau 

 between fifty and one hundred feet above the adjoining fen- 

 land. Its origin is yet unexplained. It is chiefly of interest 

 on account of its flora. This is specially marked in the old 

 gravel-pit of Chippenham, as noticed by Prof. C. C. Babington. 

 The plants appear to have settled there, owing to the similarity 

 between this gravel and the sandy deposits of East Norfolk 

 and Suffolk, though those deposits have an origin different 

 from that of the Chippenham gravels. 



The climate of Cambridgeshire is summed up in the Geo- 

 logical Survey Memoir on "The Geology of the Neighbourhood 

 of Cambridge " as follows : 



" The physical conformation of the ground is (with the 

 exception of the chalk slope) such as to induce dampness of 

 soil and atmosphere ; a characteristic which, as regards Cam- 

 bridgeshire, has become proverbial. It is owing, not to the 

 rainfall which in amount is small, about 23 inches a year, but 

 to the low-lying area being surrounded by higher ground on all 

 sides but one, by the preponderance of ground sloping to the 

 north, and by the prevalence of clay soils." 



