70 Rev. A. Sedgwick on the Geological Relations and 



a proof, both in natural sections and in various coal-works, that the deposit occupies its proper 

 place, though in a very imperfect form. J'urther north it is much more developed ; and at Scare, 

 croft Mill, Rigton, and the hill above Collingham, is seen in its most characteristic form. It is 

 also laid bare in a very singular denudation on Bramham Moor, and the south-eastern extremity 

 of Bramham Park, considerably within the limits of the limestone, where it is chiefly composed 

 of a singularly coarse grey sandstone, which contains such an abundance of kaolin as to be in 

 many places incoherent*. The deposit is in this district of very unequal thickness, and probably 

 extends in irregular patches considerably beyond the western limits of the escarpment, accom- 

 panying the various outliers which have been enumerated in a former part of this paper. 



In the greater part of the range from the Wharfe to the Nid, the sandstone forms an advanced 

 terrace, which ranges considerably to the west of the plateau of the magnesian limestone ; and 

 its prevailing character is that of a coarse irregularly bedded purple-coloured sandstone, some- 

 times nearly approaching the appearance of a conglomerate, and decomposing into irregular 

 masses presenting many complicated forms of great picturesque beauty f. Possessing nearly the 

 same characters, it is laid bare in many of the nol)le sections which are presented in the great 

 cleft, which, on the south side of Knaresborough, allows a passage to the waters of the Nid. In 

 some of the quarries it consists of the usual coarse sandstone, with kaolin and fragments of felspar 

 crystals ; in others it passes into a strong red or variegated sandstone, often falsely bedded, with 

 bands of red marl, occasionally with concretions of ochre; and near the top it here and there 

 presents thin beds of micaceous incoherent sand mixed with red marl. 



To the north of Knaresborough it is seen in scattered blocks in a few quarries on Scotton and 

 Breareton Moors; and again in Scara quarries north of Ripley, and on both sides of the rivulet 

 below South Stainley. It is therefore extended, though probably in unconnected masses, several 

 miles to the west of the limestone terrace. It is however difficult, and perhaps impossible, to 

 determine its precise limits ; as it makes no escarpment, and can hardly be distinguished from 

 some varieties of millstone grit which range through the same district. The remaining part of the 

 terrace, which terminates at Watlas, is so much disguised with diluvium, that it is hardly possible 

 to trace the beds I am describing. We may, however, conclude from the indications of a few- 

 natural sections, and still more from the number of loose blocks in the diluvial detritus, which 

 agree in character with the inferior red sandstone, that the formation is probably coextensive 

 with the limestone. 



The extensive destruction of the superior formations between Bedale and the banks of the 

 Tees, and the accumulations of incoherent matter, make it almost a hopeless task to seek for the 

 red sandstone in that district. At the same time the low position of the few patches of magnesian 

 limestone which remain, make it probable that the sandstone was very imperfectly developed 

 before the denudations were effected. 



In the flat region immediately north of the Tees, it appears hardly possible, for want of sections, 

 to ascertain the nature of the beds which range under the limestone : and the relations of the lofty 

 sandstone hills which pass along its north-western skirt between Houghton. le-Side and Brussleton 

 Tower, are far too obscure to be easily determined. These hills are chiefly composed of a grey 

 sandstone rock of very varied texture, but affording some excellent quarries which have been used 



* See Plate IV. No. 2. 



t The scenery in the neighbourhood of Plumpton shows the character of the rock in great 

 perfection ; and if an unmeaning designation is to be given to it, merely borrowed from some 

 locality where it is well exhibited, I think the term Plumpton sandstone might be adopted with 

 advantage. 



