268 



Fanning of Lincolnshire. 



dark-coloured limestone the soil is often very thin, and prin- 

 cipally composed of minute fragments of the rock. 



The Oxford aiid Kimmeridge Clays are not separated in Lin- 

 colnshire by the coralline oolite, or calcareous grits, and therefore 

 form one thick bed of clay, the boundary between the two being 

 undistinguishable ; and the principal part of their surface is 

 buried under deposits of drift and the alluvium of the Anc- 

 holme level and southern fens. A narrow line of it is found 

 along the foot of the hill east of Kirton-in-Lindsey, lying be- 

 tween the high land and the Ancholme carrs. It is called the 

 " Carr heads," and forms a stiff clay soil, bad in quality. This 

 extends southward to the river Witham, through Cold Hanworth 

 and Sudbrooke, being a cold clay, very narrow, and bounded 

 east by the detrital deposit of the central valley. On the south- 

 west side of the VVitham fens it is interspersed with the beds of 

 drift, occupying a small portion of the surface in the parishes 

 on the lower range of hill east of the heath. The soil varies 

 from a mild friable loam to a very tenacious clay. This extends 

 to Timberland and Billinghay, where it forms a bold promontory 

 of high land advancing into the fen, and beyond it toward the 

 south (through North and South Kyme) it forms an island of 

 high ground rising out of the fen-land ; but the clay is frequently 

 hidden by deep layers of transported earths. In the district 

 south and east of Sleaford, by Scredington, Osbournby, &c., it 

 is a stiff clay, harsh, and difficult to work; and through Burton- 

 Pedwardine, Helpringham, Swaton, and other parishes, the 

 strong clay land continues. From near Folkingham to Edenham 

 and Bourn it is a close, heavy, compact clay, producing beans, 

 wheat, oats, and clover, and much of it is under grass. At 

 Kirk by- Underwood it forms beautiful pasture-land, dry enough 

 for sheep, and rich enough for horned cattle. Along its whole 

 course this bed dips under the fens, and exhibits an undulating 

 surface of but trifling elevation. From Bourn to Thurlby, &c., 

 it is a various soil, probably owing to the alternating layers of 

 hard sand and clay of which it is composed ; much of it is poor 

 land, and the pastures are very subject to parching in hot sum- 

 mers. East of the Ancholme flat the clay runs in a low ridge 

 from near Brigg through Cadney and Kelsey, Owersby, Kingerby, 

 &c., being a very strong but fertile soil, and forming excellent 

 pasture. It is very narrow, and, sloping to the east, underlies a 

 broad flat tract of sand that stretches between it and the Wolds. 

 This is probably the Kimmeridge clay, but it is difficult to dis- 

 tinguish it from the Oxford clay, as the stone band (viz. the 

 coralline oolite), which has its place between these beds, thins off 

 and disappears in its course northwards from the midland counties. 

 These clays form a mass of enormous thickness, which, it is be- 



