UPPER POETION OF DUNDRY HILL. 221 



Main-road quarry, some five feet below the present floor of 

 that opening. They could be found at many places. Next 

 to these beds, the rubbly coralline deposits furnish a fairly 

 hard stone for road metalling ; so do the thin-bedded equiva- 

 lents of the Freestone in the roadside quarries and Barns 

 Batch quarry, and the small waste from the upper or 

 inferior bed of freestone in the Freestone quarry. 



3. The Water-hearing Beds of Dundry Hill. 



Springs issue at two principal levels, and occasionally at 

 two or three others, on the upper slopes of Dundry Hill. 

 The chief level for large springs is at the tor) of the shales 

 of the Dumortieria-heds, the water issuing out in streams 

 often of considerable volume and of great persistence at 

 the level where the Aalenian limestones rest upon these 

 impervious argillaceous strata. This is the chief water- 

 bearing bed of the Dundry village : in fact, it is because 

 th.e Dumortieria-heds are clay that the houses of Dundry 

 occupy their present position : had the Dumortieria-heds 

 been sands, the water-level would have been nearly fifty 

 feet lower down than it is now. 



The level next in importance for springs is the base of 

 the Marlstone Rock, from which water is thrown out at 

 various points along the eastern portion of the northern 

 escarpment and also on the sides of the valley below East 

 Dundry. 



At certain points on the western side of the hill, where 

 the Marlstone Rock is absent, or, if present, exists in such a 

 fluctuating and attenuated form as to have hitherto escaped 

 detection, springs occasionally break out from the " bifrons- 

 beds " : the Elwell spring, south of Castle Farm, is an 

 example. The " Cephalopod-bed," or " bifrons-heds," also 

 often gives out small springs on the hillside, both on the 



