492 On tJic Agricultural Geology of England and Wales. 



occupied on geological maps by different formations. In others 

 political boundaries only are given, and the varieties of soil, 

 under their local names, are enumerated by parishes. 



In Yorkshire we can readily identify the eastern moorlands, 

 the tabular hills, the vales of Pickering and Cleveland, with the 

 lower oolites, the coralline oolite, the Kimmeridge clay, and the 

 lias. In Lincolnshire, on the other hand. Young has but two 

 divisions west of the chalk, namely, the upper part of the lower 

 oolite on Lincoln Heath, and a district of various soils, comprising 

 the out-crops of all the strata between the chalk and the new red. 

 Stone, who made a second report on that county, disposes of the 

 varieties of soil in a more summary manner, by the declaration 

 that Young's descriptions do not comprise one-fiftieth part of 

 the soils to be found there, and that a man who knew them well, 

 and was not fond of much writing, would not waste his time 

 and paper on them, unless he was able to be more particular. 

 The western clay district of the Cambridgeshire agricultural map 

 includes the brown clay or till of the western side of the chalk 

 ridge, and the outcrops of the gault and Kimmeridge and 

 Oxford clay. In Oxfordshire we have three geological areas, 

 tolerably well defined, subject to internal variations : the red soils 

 of the lower oolites — " the glory of the county," — the cornbrash, 

 and between that and the chalk, the usual resource of a district of 

 ''various soils" occupying two-thirds of the entire county. 



It was on the coralline oolite of the tabular hills at Hackness** 

 that Smith achieved one of his geological triumphs, described by 

 Sir John Johnston. Smith's map of the Hackness estate proves 

 two points of great importance — the necessity of indicating on 

 maps intended to be useful for agricultural purposes, the mineral 

 characters of even the minor subdivisions of a formation, and of 

 indicating also the areas covered by remains of the erratic ter« 

 tiaries, even in districts from which they have been most denuded, 

 and in which the influence of the substrata on the soil is at its 

 maximum. 



The productiveness or unproductiveness of certain fields at 

 Hackness was found to depend on the calcareous or non-calcareous 

 character of the oolite strata on which they rested ; while on a 

 neighbouring height an outlier of the erratic tertiaries not only 

 modified the usual agricultural character of the rock which it 

 covered, but had thrown out springs, which had led other managers 

 of the estate to a considerable expense in sinking for water on 

 neighbouring hills, in which, from the absence of this deposit, it 

 was only to be met with at great depths. 



If the erratic deposits were thus found by Smith to exercis© 



* Journal of the Eoyal Agricultural Society, vol. i. p. 273. 



