274 



BULLETIN OF THE 



The right bank 



Greenwood Lake Railroad crosses the mountain. As the valley is in 

 line with the larger fault, they probably stand in the relation of effect 

 and cause ; the throw has very probably increased where the valley is 



well formed. 



Sandstone was not found in the valley as far south as the Notch, 

 although the j)lace is favorable for its preservation. If continued north- 

 ward, the fault would pass east of the trap front at the Falls, and its 

 effect, if existing thci'C in the sandstone, woidd be less noticeable. 



On the western foot of First Mountain two small exposures just west 

 of the Morris Canal and south of the High Bridge showed amygdaloidal 

 trap, and one of them presented clear marks of variation in structure 

 bounded by curved surfaces, such as are found farther south at Fclt- 

 ville. There was also seen at this point a surface much like that of 



flowing lava or slag. 



Sandstone is not seen in the flat valley until the village of Little Falls 

 is reached, a short mile west of the First Mountain trap, where it is 

 shown in normal condition in a quarry by the canal and river, about 

 two hundred yards east of the Second Mountain trap, 

 of the Passaic here approached gives no chance of finding a junction ; 

 but on the other side, a little farther down than opposite the quarry, 

 there is a small opening in which fine trap and red sandstone both show, 

 though the contact, is hidden by several feet of rubbish. The sand- 

 stone has no marks of baking. Following up stream, the trap varies 

 greatly in texture ; an irregxdar very amygdaloidal mass grades into 

 firm trap on one side, and into a much decomposed loose rock on the 

 other; I have considered the latter an ash or tuff. The dense trap is 

 often distinctly columnar, and above the canal bridge it is well divided 

 by nearly horizontal open joints into sheets of varying thickness. In 

 the midst of this there is a very uneven mass of amygdaloidal trap that 

 seems to contain fragments. Farther west there is a broad area of flat 



alluvial meadow-land. 



The trap of this region is described by Rogers (c, 146) and Cook 



. (6, 179). 



M. Feltville, N, J. (figs. 49, 50). — Mr. I. C. Russell {a) describes an 

 npper contact in a little ravine on the back of First Mountain near this 

 deserted village; but I failed to discover any outcrops corresponding 

 closely to his description. My time there was shoi^t, and allowed only 

 the examination of a ravine about an eighth of a mile east-northeast of 

 the village ; the stream from it enters the brook in Washington Valley 

 at the lower part of an old broken dam. Going about one hundred yards 



!J 



