482 T. C. Cantrill — Coal-boring at Presteign, Radnorshire. 



Folly Farm, three-quarters of a mile south of Presteign. From 

 the eastern suburb of the town a lane, turning southward out of 

 the Tenbury road at the County Intermediate School, crosses the 

 railway and rises towards the ridge of Nash Wood and Corton. At 

 the foot of the ridge the lane bends to the south east, climbs the 

 Folly Bank by a diagonal course close to the site of the boring, and 

 soon reaches the summit at the Folly Farm (Fig. 1). 



Fig. 1. — Sketch-map of the neighbourhood of Folly Farm, Presteign. Scale 

 6 inches to a mile. B.H., bore-hole ; W.L., Woolhope Limestone. 



The mouth of the drift can be seen at the foot of the ridge, about 

 60 yards west of the bend in the lane, and 140 yards west-by -north 

 of the borehole. The excavation was driven in a direction bearing 

 about S. 16° W., i.e. at right angles to the trend of the ridge, and 

 descends at a slight angle from the horizontal. It thus cuts the 

 beds in descending order at about right angles. Judging by the 

 amount of material brought out, it must have penetrated a consider- 

 able distance into the hill-side before it was abandoned through 

 lack of further funds. 



Murchison ' in 1839 sketched the outlines of the geology of 

 Presteign in the classic pages of The Silurian System. He clearly 

 perceived the anticlinal structure of the Nash and Corton ridge, and 

 its connexion with the disturbed region of Old Radnor. He saw 

 that the visible core of the ridge is composed of grits and con- 

 glomerates, which he correlated with the upper beds of the Caradoc 

 Sandstone of Shropshire, and that these grits rise on each side from 

 beneath a calcareous zone, which he regarded as the equivalent of 

 the Wenlock Limestone. He noted also that the grits contain the 

 characteristic fossils of the upper beds of his Caradoc Sandstone, 

 e.g. Pentamerus oblongus and P. lavis, and that the overlying lime- 

 stone, which, on the northern side of the ridge, 2 occurs in the form 



1 Silurian System, pp. 313, 314, 321, 322. 



2 This outcrop has been variously referred to as the limestone at the Folly 

 (Murchison), at Folly Bank (J. E. Davis), at Corton (Murchison and W. S. 

 Symonds), and at the Sandbanks (J. E. Davis). It will facilitate description 



