Northumberland and Durham. 



Analysis of 100 parts of Limestone. 



By the Rev. J. Holme. 

 From Denton. 



By Sir H 

 From Eldon. 



Davy. 



From Ay cliff. 



Carbonate of Lime 



of Magnesia 



Alumina, Red Oxide of Iron, i 

 and Bitumen. $ 

 Water 



. 63 

 . 34 



. 2.25 



.25 



52. 



45.2 



48.9 



46.6 



Iron 1.1 



Residuum.... 1.7 



100. 



1.66 



2.8 





100. 



100. 



In a quarry at Hartlepool I have noticed a stratum of hard white 

 oolite, the grains composing it being about the size of a mustard 

 seed-; but, unlike the Ketton and Riflington roe-stones, it contains 

 no shells or marine exuvise. I have found at the same place a bed 

 of pale buff coloured limestone of an earthy fracture, punctured 

 with holefr not larger than a needle's point. The ornamental parts 

 of the old exchange at Newcastle were carved out of these two 

 varieties of stone. 



The four lowest strata of Mr. Goodchild's quarries at Pallion 

 near Sunderland, constitute another variety. Its colour is a dirty 

 light brown ; but taking a tolerably good polish it is sold as a 

 marble. In lustre and hardness it resembles a stalagmite ; it is met 

 with at the depth of eleven fathoms from the surface. 



In Castle Eden Dean there are cliffs of this rock well worthy 

 of notice; and the perforated rocks at Marsden and Hartlepool, 

 and the caverns at the latter place, at Black-hall near Easington, 

 and on the coast near Monk Wearmouth, deserve the attention 

 of the geologist. These curious and picturesque objects appear to 

 have been formed at no very distant date by the action at the sea, 

 which has dissolved and washed out the soft marly limestone, with;. 



