ALLUVIAL COVERING. m 



all Holderness, with the environs of Hull and Beverley, and the rest 

 of the flat country to the south of the Wolds^; extending in length 

 from the Spurn to Bridlington, a distance of about thirty-six miles,- 

 and in breadth, from the coast to the chalk hills on the west of Hull 

 and Beverley, about sixteen miles. Besides this large alluvial tract, 

 which is continued beyond the Humber, on the Lincolnshire coa&t,. 

 there are several other parts of the district where nothing but alluvium 

 i§ accessible. This is the case with most of the extensive vale of 

 Pickering, which opens towards Filey bay, where we find chiefly ait 

 alluvial ' cliff. In some parts of Robin Hood's bay, Sandsend bay, 

 and Runs wick bay, the cliffs are also alluvial ; and the plain of Cleve- 

 land presents, in many places, a deep covering of the same description. 



It is scarcely necessary to observe, that this alluvium, occurring 

 where no rocks are discernible, is not materially different from that 

 which covers the regular strata, where the latter make their appear- 

 ance. We may remark, however, that the alluvial beds, as might be 

 expected, are usually thinnest where the strata are most elevated; 

 and in some parts of our hills the rocks rise to the very surface. 



This part of the crust of our earth is called alluvium, because it 

 appears to have been formed bj the wasJiing mvay of the other strata. 

 It resembles the banks of rivers, formed by the accumulation of sand, 

 gravel, mould, and other substances, brought down by the floods, 

 and deposited in successive layers, wherever the waters overflow the 

 lands adjacent to their wonted channels. Every river, except where 

 its course is very rapid, or confined by rocks, has alluvial banks of 

 this description, of more or less extent. The beds that cover the re- 

 gular strata present the same kind of structure, though on a much 

 larger scale, consisting of vegetable mould, sand, gravel, clay, marl, 

 fragments of stone, with other substances, Aariously blended and 

 arranged; sometimes disposed in beds or layers, and sometimes ex- 

 hibiting a confused mixture. 



