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large blocks, forms a good building stone. The latter kind is often 

 beneficially applied to the soil, being identical, in fact, with the 

 pond or swamp marl already spoken of 



The travertin, or calcareous tufa, which is another name it 

 bears, exists in both these varieties, on the Little Flatkill, about 

 two miles southeast of Dingman's Ferry, being deposited a few 

 hundred yards from the base of the Limestone Hill by a small 

 rivulet. A similar collection of this material occurs nearer to 

 the river side, a little above the ferry; and traces of its existence, 

 though in rather small deposits, are not unfrequently noticed 

 along both bases of the ridge for a distance of several miles. 



Subjoined is an analysis of the travertin deposit, as found near 

 Dingman's Ferry. 



Composition. — In 100 parts : 



Carbonate of lime, . - . 93'53 



Carbonate of magnesia, - - 0*15 



Alumina and peroxide of iron, - 0*42 



Insoluble matter, - - - - 4-24 



Organic matter, moisture, and loss, 1-66 



10000 



The position which the limestone belt holds in relation to the 

 valleys of the Delaware and the Flatkill, enables the farmers of 

 this favoured region to avail themselves of its fertilizing treasures, 

 throughout its whole range through Sussex, as it is nowhere 

 more than two or three miles from the two cultivatable tracts 

 which border it. But notwithstanding that the beneficial action 

 of lime on the soils along the river, and on the more gravelly lands 

 of the Flatkill and its adjacents hills, has been long admitted by 

 experience, there still exists on the part of many farmers, a singu- 

 lar indifference to this most important agent in agriculture. 



Of the Circumstances which attended the Production and Eleva- 

 tion of the several JJppalachian Rocks above described. 



To comprehend fully that succession of actions which gave to 

 the northwestern side of New Jersey its present symmetrical 



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