284- ON THE FREESTONE QUARRIES OF 



this catalogue, is to encourage some member of the Society, 

 who may read it, and whose opportunities of collection are 

 better than my own, to remedy this loss. — All these specimens 

 may be procured with very little trouble in Virginia. 



The loss of this collection dispirited me, and the occupa- 

 tions of a most laborious profession deprived me of time. Hav- 

 ing now for some years waited in vain, for the leisure necessa- 

 ry to reduce into something like system, the various notes I 

 have made, I must content myself with giving to the Society, 

 unconnected papers, which will contain the facts collectively, 

 proving beyond doubt, that a line drawn along the falls of our 

 rivers, is the ancient line of our sea coast, from New-York to 

 the south west; as it still is from New- York to the north east- 

 ward, and that the water of the ocean rose, perpendicularly, 

 at least 120 feet higher along the ancient coast, than it rises 

 along our present coast. — And lest this assertion should appear 

 extravagant, I will here mention, somewhat out of place, that 

 in the year 1796, I followed with a spirit level, in the neigh- 

 bourhood of Richmond, the pebble stratum, which has all the 

 external appearance of a sea beach, for more than five miles, and 

 found it a perfect level, elevated about 120 feet above the tide at 

 Rockets. — The subject of my present communication, is imme- 

 diately connected with the memoir on the sand hills of Virginia. 

 Its object is, to give to the Society, an account of the freestone 

 quarries on the Potomac and Rappahannoc, from the form- 

 er of which, the freestone employed in the public buildings 

 of the United States at Washington, is obtained. — The range 

 of sand stone rocks in which the quarries are situated, was, in 

 fact, the ancient sea coast, bounded by sand hills like the pre- 

 sent, and the description which I shall give of them, will, I be- 

 lieve, remove all doubt on this subject. 



On consulting the map of the middle states, it will be found, 

 that the river Potomac, at the confluence of the river Pisca- 

 laway, in Maryland, a few miles above Mount Vernon, takes 

 a remarkable turn to the south of west, and continues to run in 

 a south westerly course, as far as the confluence of Acquia 

 creek, on the Virginia side, when it gradually turns to the east 

 of south, and in the course of ten miles lower, pursues a north 



