XXIV. Observations respecting the Limestone of Plymouth, extracted 

 from two Letters, dated September 26, 1814, and January 19, 1815, 

 addressed to Henry Warburton, Esq. Secretary. 



By the Rev. RICHARD HENNAH, Junr. 



CHAPLAIN TO THE FORCES AT PLYMOUTH. 



Citadel, Plymouth. 

 &INCE the date of my letter of the 8th of August last, in which 

 I mentioned that organic remains were found in our limestone at 

 Mill Bay quarry, various shells and fossils have been discovered in 

 our limestone at other places. The limestone between the Tamar 

 and Plym rivers, extends over a tract above three miles in length ; 

 its strata run nearly parallel to one another from north-west to 

 south-east, dipping towards the south-west, this being also the po- 

 sition of nearly all the stratified rocks in the neighbourhood. The 

 westernmost point at which shells have hitherto been found is the 

 Dock Yard. A few weeks ago some workmen found petrified bi- 

 valve shells imbedded in the solid rock, twenty feet below the sur- 

 face, while removing the remains of a small mount called Bunker's 

 Hill, which had been left when the Dock Yard was excavated. I 

 have since visited the spot myself, and found several specimens in 

 situ. 



Further to the eastward organic remains have been noticed, on 

 Stonehouse Hill, both above and below the road at the entrance of 



