120 Dr. BucKLAND on the Formation of Valleys by Elevation, 



The red lines on the map, extending from the village of Inkpen to High- 

 clere, mark the southern and south-western outcrops of the formation of Plastic 

 clay, as displayed on the surface at several interrupted points, and as used in 

 many places for brick-earth. It presents the same irregular alternations of 

 brick-red, mottled, and occasionally blackish clay with loam, sand and rounded 

 chalk-flint gravel, which occur in this formation at Reading, Blackheath, and 

 wheresoever else it presents itself within the basins of London and Hamp- 

 shire. Occasionally also, as at Kintbury on the west of Newbury, it contains 

 the same organic remains, in the same state of preservation, as in the well- 

 known clay-pits at Reading ; viz. oysters, sharks' teeth, &c In the blacker 

 beds of clay there is abundance of vegetable matter and wood, constituting the 

 same kind of imperfect brown-coal that attends this formation at Blackheath, 

 Alum Bay, and Corfe Castle. The lowest stratum of the formation, or that 

 next above the chalk, consists, in this instance also, for the most part of sand ; 

 and at its actual contact with the chalk, is often loaded with flints, which are 

 coated superficially with either a green or brown rusty crust. The sand is 

 fine and siliceous, and is interspersed, as usual, with particles of green-earth. 



Into this western and uppermost extremity of the great chalk-basin of Lon- 

 don, the London clay penetrates to a considerable extent, the limits of which 

 clay it is foreign to my present purpose to investigate ; whilst the greater number 

 of the minor hills round Newbury are composed of loamy sands and clays of the 

 Plastic formation, occasionally denuded, in the valleys, down to the subjacent 

 chalk. Several extensive plains that still remain in heath and commons, are 

 composed of extremely sterile sand-beds, more or less mixed up with gravel*. 



* The following observations on the gravel of this district are extracted from a letter to the 

 author by J. R. Gowen, Esq. of Highclere. 



" It is almost impossible to define the relative quantities of gravel and clay in the vale of New- 

 bury. Nothing can be more irregular than their distribution, though in general it may be as- 

 sumed, that in the commons, such as Newbury, Greenham, Crookham, Sidmonton, Curghclere, 

 Aldermaston, Mortimer, &c., gravel, covered with a very shallow stratum of black sandy soil, 

 greatly predominates. This black sand is of the most sterile nature, bearing nothing but heath, 

 and a few of the worst species of grass, scattered in thin patches at large intervals, and sometimes 

 nothing but lichens. It is important, however, to observe that this barren sand has been made to 

 bear good corn-crops, and been totally reclaimed by the action of chalk when applied in large 

 quantity. Anthony Bacon, Esq. of Benham, near Newbury, Messrs, Batten and Bridgeman of 

 Highclere, and others, upon land of this description rented of Earl Carnarvon, have applied chalk 

 with most extraordinary success ; and I have seen land which was almost utterly unproductive 

 of food for man or beast, and seemed destined to irreclaimable barrenness, after being broken up 

 and heavily chalked, become loaded with fine crops of wheat and turnips, &c. 



" Mr. Bacon tried the effect of dung without calcareous matter most fully, and without success ; 

 the manure only producing a more luxuriant growth of a small Arenaria that strangled the corn 



