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matters of local interest not appropriate in a general account of 

 the formation, I shall here introduce a series of descriptions 

 embracing the principal localities where the marl is at present 

 excavated. 



Pursuing the usual order adopted, in tracing the local features 

 of the other formations of the State, that is to say, proceeding 

 from the northeast towards the southwest, I shall commence with 

 the township of Middlesex, in Monmouth county. 



Middletown Point. — The lowest portion of the greensand stra- 

 tum, where it passes into the underlying blue sandy clay, is exposed 

 at several places in the vicinity of Middletown Point, which is a 

 little outside of the boundary designated as the northwestern edge 

 of the formation. The proportion of the green granular mineral 

 in the marl of this neighbourhood, is, therefore, less than where 

 the higher layers of the greensand are most developed, towards 

 the southeast. 



On the farm of Mr. William Little, not far from Middletown 

 Point, the stratum is of a light ash-gray colour, inclining some- 

 what to greenish. Though it contains a large excess of clayey 

 matter, the green granules are readily discoverable. These 

 particles after separation from the marl by washing, are of a 

 light clear green. 



The composition of this marl is, in 100 parts: 



Greensand, - - - 46-73 

 Clay, .... 53-27 

 Quartzose sand, - - none. 



10000 



Assuming the proportion of the potash in the green grains to be 

 11'5 per cent., which is the mean of the fifteen systematic ana- 

 lyses given in a preceding chapter, we find the amount of the 

 alkali in this marl to be 7*47 per cent., a quantity capable of 

 imparting very decided fertilizing effects. 



Mount Pleasant. — One of the most northern points where the 

 stratum is dug for marl, is upon a farm of J. Morgan, near Mount 

 Pleasanl. In the same neighbourhood a marl of very similar 

 quality, is found underlying a part of the farm of Mr. Castle- 

 reagh, near the northwestern base of the belt of hills lying south 



