47 



occupying a confined area upon this ridge, is very limited. The 

 rock is of a grayish white, has an even texture, dresses readily 

 under the hammer of the mason, and is, in many respects, entitled 

 to attention as a material well adapted for architectural uses. 

 It has been occasionally emplo3'ed with that view at Hacketstown. 

 Almost every where else along the boundary which separates 

 the limestone from the primary rocks, where this formation should 

 be found, we find either no traces of it whatever, or else here and 

 there a debris, consisting of a white sand and gravel, derived 

 from the destruction of the rock at its outcrop. The frequent 

 accumulation of the large deposits of diluvial matter at the bases 

 of so many of the primary hills, together with the easy dcstructi- 

 bility of the rock itself, which can nowhere within the State have 

 attained to a great thickness, will serve to explain the very 

 limited extent to which it is exposed. 



SECTION II. 



Of the Blue Limestone {Formation 11.) of the Kittatinny Valley and 

 , its Branches. 



The second rock of the Appalachian series which we meet 

 with in the ascending order, is the great blue limestone formation 

 of the southeastern half of the Kittatinny Valley, and of most of 

 the valleys included between the several ranges of the primary 

 hills, or Highlands. 



Geological range of the Formation. — Omitting, for the present, 

 the task of tracing the lesser belts of the blue limestone, which 

 occupy the narrow longitudinal valleys of the primary chain and 

 the valley of the Paulinskill, and restricting our attention to the 

 principal tract of this formation in the State, we may define it in 

 general terms, as occupying the southeastern half of the Kitta- 

 tinny Valley, understanding this name in its most comprehensive 

 sense as extending to the base of the long continuous mountain 

 range, known as the Wallkill, Schooley's, and Musconetcong 

 Mountains. Within this broad belt rise up a number of the de- 

 tached primary ridges of the general chain of the Highlands, 

 whose exact position and boundaries we have already traced. 



The continuity of its surface is still further interrupted near its 



