<U4 OBSERVATION'S ON THE GEOLOGY 



The great distance occupied by the same, or similar sub- 

 stances, in the direction of the stratification, must strike the ob- 

 server; as in the primitive rocks, the beds of primitive limestone 

 and Dolomite (containing in some places crystallized felspar 

 and tremolite) which are found alternating with Gneiss, for ten 

 miles between Dover, State of New- York, and Kent, State of 

 Connecticut, appear forty miles north, at Stockbridge, Con- 

 necticut, and eighty miles south, between Singsing and Kings- 

 bridge', New- York; where, after crossing the Hudson river and 

 dipping under the trap and sandstone formation in New-Jersey, 

 they most probably re-appear in the marble quarries, distant 

 from twelve to fourteen miles N. W. of Philadelphia, — a range 

 of nearly 300 miles. 



There is a bed of magnetic iron ore, from eight to twelve 

 feet thick, wrought in Franconia, near the White Hills, New- 

 Hampshire; a similar bed in the direction of the stratification, 

 six miles N. E. of Phillipstown, on the Hudson river; and still 

 following the direction of the stratification, the same ore occu- 

 pies a bed of nearly the same thickness at Ringwood, Mount- 

 Pleasant, and Suckasunny, in New-Jersey, losing itself as it ap- 

 proaches the end of the primitive ridge, near Blackwater, — a 

 range of nearly 300 -miles. 



Instances of the same occur in the transition and secondary 

 rocks; as the Blue ridge from the Hudson river to Dan river, 

 consists of rocks of much the same nature, and included in the 

 same formation. 



That no volcanic productions have yet been found.east of the 

 Mississippi, is not the least of the many prominent features of dis- 

 tinction between the geology of this country and that of Europe," 

 and may perhaps be the reason why the Wernerian system, so 

 nearly accords with the general structure and stratification of 

 this continent. 



It is scarce necessary to observe, that the country must be 

 considered of the nature of the first rock that is found in place, 

 even should that rock be covered with thirty or forty feet of 

 sand or gravel, on the banks of rivers, or in valleys; for ex- 

 ample, the city of Philadelphia stands on primitive rock, 

 though at the Centre-square, thirty or forty feet of sand and 



