Geology of Herefordshire, Sjc. 46 



plored to the N.E., we arrive at the foot of May-hill, the pharos 

 of the country ; and here I am told some additional stratifica- 

 tions abounding with fossils, mark the limits where we cease 

 to recede from the vestiges of organic existence. From the 

 forest borders to the banks of the Severn, we find a continued 

 mine of unexplored geological treasures ; crossing that river 

 we tread upon ground abounding in mineral varieties ; and I do 

 not scruple to say from personal knowledge, a region which 

 equally with any other in Great Britain, will prove interesting 

 to the mineralogical traveller. Through the kind communica- 

 tions of Henry Shrapnell, Esq., and my invaluable friend Dr. 

 Jenner, and a sight of their specimens, of which many are ex- 

 ceedingly rare, and connected with some important elucidations, 

 I am enabled to give a bare list of the Gloucestershire series. 



From below upwards. 



1. Old red sandstone 



2. Blue lias 



3. Oolite 



4. Inferior ditto 



5. The clay rag-stone 



6. Superior oolite. 



In another direction towards Bristol from Berkeley. 



Transition limestone cut through with the dyke 



of volcanic trap at Mickleham 

 Magnesian limestone 

 Millstone grit 

 Mountain limestone. 



The Mickleham trap in the parish of Berkeley, was first ob- 

 served by Dr. Jenner. I was very much struck when first 

 shewn a considerable quarry of this basaltic rock, excavated in 

 such a manner as to uncover its magnificent globous structure, 

 in the midst of a wood, seated on the side of a hill. Mr, 

 Shrapnell and myself traced its sides, where the limestone and 

 sandstone were cut off. The length of its sections, or its ge- 

 neral extent, I am unable to give from the loss of my notes ; it 

 abounds with minerals, contained in Jtssurcs near the surface, 



