262 



The proportion of potash which this marl contains, deduced 

 from that of the green grains, is 9-7. 



Lower portion of the stratum. 



Description. — Colour, bluish-gray, texture clayey and tena- 

 cious. The washed granules dark, almost black, and very large. 



Composition. — In 100 parts: 



Greensand, ... 77*45 



Clay, .... 22-55 



Quartzose sand, - - none. 



10000 



The proportion of potash, by analysis, is 9 per cent. 



It is an observation made in this neighbourhood, and one in 

 complete accordance with my observations throughout the marl 

 tract, in its range from hence through Burlington and Gloucester 

 counties, and even Salem, that when the light green shows itself 

 it is usually along the eastern side of the marl belt, and invariably 

 occupying a position on the top of the dark greensand. The 

 latter, I find in many districts to be esteemed the most efficient of 

 the two varieties. 



At Snuff Mill, on a small tributary of Crosswick's creek, about 

 one mile north of New Egypt, we witness the same limestone 

 bed which appears lower down the State, at Vincentown, and in 

 Salem county. It holds the same position on the top of the green 

 marl, is a stratum of about a foot in thickness, and contains the 

 same corals or zoophytes — for example, the same alcyonia, and 

 the same shells seen in the districts where this stratum of rock is 

 of more important thickness. 



At Fuller Horner's, on Crosswick's creek, about a third of a 

 mile below New Egypt, there is a bank exposing the strata, where, 

 during the last twenty years, enormous quantities of marl have 

 been procured for the use of the neighbourhood. The section is 

 between twenty and twenty-five feet high. Near the top of the 

 bank, the upper layer is a greenish siliceous and slightly calca- 

 reous sand, and beneath this occurs the rubbly, straw-coloured, 

 and somewhat sandy limestone, the frequent capping to the marl. 

 Both these layers are represented in precisely the same order 



