16 THE NATURAL HISTORY 



soon as they were exposed to the rains and frost they 

 mouldered away. These seemed as if they were a very 

 recent production. In the chalk-pit, at the north-west 

 end of the Hanger large nautili are sometimes ob- 

 served. 



In the very thickest strata of our freestone, and at 

 considerable depths, well-diggers often find large scallops 

 or pedines, having both shells deeply striated, and ridged 

 and furrowed alternately. They are highly impregnated 

 with, if not wholly composed of, the stone of the quarry. 



LET^TER IV 



As in a former letter the freestone of this place has 

 been only mentioned incidentally, I shall here become 

 more particular. 



This stone is in great request for hearth-stones and the 

 beds of ovens : and in lining of lime-kilns it turns to 

 good account ; for the workmen use sandy loam instead 

 of mortar ; the sand of which fluxes,* and runs by the 

 intense heat, and so cases over the whole face of the 

 kiln with a strong vitrified coat like glass, that it is well 

 preserved from injuries of weather, and endures thirty or 

 forty years. When chiselled smooth, it makes elegant 

 fronts for houses, equal in colour and grain to the Bath 

 stone ; and superior in one respect, that, when seasoned, 

 it does not scale. Decent chimney-pieces are worked 

 from it of much closer and finer grain than Portland ; 

 and rooms are floored with it ; but it proves rather too 

 soft for this purpose. It is a freestone, cutting in all 

 directions ; yet has something of a grain parallel with the 



* There may probably be also in the chalk itself that is burnt for 

 lime a proportion of sand : for few chalks are so pure as to have 

 none. 



