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the deep covering of diluvium which forms these plains. At the 

 spot last mentioned, the conglomerate was disclosed by some over- 

 credulous miner in an excavation for silver ore, led astray by the 

 occurrence of very minute crystals of yellow sulphuret of iron. 

 The rock is nearly all limestone, and specimens which have been 

 polished, prove exactly identical in character with the Potomac 

 marble. The conglomerate is traceable along the side of the 

 Ramapo river, near Ryerson's barn, where it has the same dip 

 and general composition as elsewhere, though it is less calcareous. 



The next place at which we witness unequivocal traces of the 

 formation, is at the foot of the inclined plane, upon the Morris 

 canal, at Montville. It there forms the abutments of a mill-dam, 

 where it will be found to agree very strictly with the slightly cal- 

 careous variety which forms the lowest part of the stratum upon 

 the Delaware. At Montville the pebbles are often very large, 

 and consist principally of primary rocks and red sandstone, so 

 that it would be useless to attempt burning it for lime, although a 

 more calcareous layer may possibly occur nearer the top of the 

 stratum, or which is the same thing, a little farther to the north- 

 west, that being the direction of the dip of the stratum at this 

 place. 



Another interesting belt of this formation is that which skirts 

 New Germantown upon its northwest, in a tract perhaps half a 

 mile wide and several miles in length, extending nearly as far north 

 as the Lamington river. At New Germantown it is an almost 

 pure limestone, and is somewhat extensively used for making 

 lime. The pebbles are of various shades of colour, blue, yellow- 

 ish, and red, and much of the cementing matter is tinged red. It 

 is susceptible of a high polish, and constitutes a beautifully varie- 

 gated conglomeritic marble. The dip of the rock in this portion 

 of its range, is somewhat various in direction, but at a uniform 

 angle of about 20°. The usual diameter of the pebbles is about 

 an inch, though many are much larger. They are not fully 

 rounded, but occasionally exhibit edges and angles, though much 

 blunted and worn, as if by attrition. The superposition of 

 this rock to the red shale or sandstone series upon which the 

 village of New Germantown rests, is very evidently shown in its 

 vicinity. On the northwest side of the little valley which borders 

 the town, we see the conglomerate; while upon the southeast 



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