290 ON THE FREESTONE QUARRIES OF 



wood : — on the Rappahannoc, loam, marsh mud, quicksand, 

 clay and dry sand : — and mar Mansfield below Fredericksburg, 

 the largest mass ot" timber, which I have yet seen : — on James's 

 river, sand, gravel, loam. The wood mixed with the stone 

 on James's river, is, I think, less carbonated than on the Rap- 

 pahannoc and Potomac. — The superstrata are generally, soft 

 clay, loam, and tolerably pure clay, in a state of excessive 

 compactness. On the level country, light loamy sand, and 

 on tne slopes of the vallies, (he line uj sea beach above mention- 

 ed, often washed and spread over the declivity, often in heaps 

 and ridges. But it will be observed by any traveller, that nei- 

 ther in the bottoms of vallies, out of the beds of the present 

 rivers, nor on the tops of the levels, is gravel to be found. 



The superstrata however vary considerably, in one of Mess. 

 Cook and Brent's quarries on Acquia, the following are the 

 strata: — 



Mould O ft - 4 in - 



Loam, with some gravel 3 



Coarse, irregular, ill compacted, disrupted sandstone 5 

 Gravel, hard clay, lumps of coarse sandstone. . 10 

 Four strata of marsh mud, and four strata of \ 

 excessively hard and pure clay, alternately, one V 8 

 foot thick each lying quite horizontally. . ) 



Loose sand 3 



29 4 



Very excellent and solid freeestone, containing 

 fewer clay holes and less wood or iron than ordi- 

 nary, 8 feet, and running out landwards to 2 feet. 

 Then sand of great depth. 



The best quarry now in work, lies two miles S. W. from 

 Acquia creek, and belongs to Mr. Robertson. Like all others, 

 it is on the top of the slope of a valley, and the face shews 

 as follows: — 



Mould l ft 



Clay, very hard, and some gravel 2 



Rough disrupted sandstone 2 



Loose sand 2 



Sound and excellent rock 15 



