274 



Marl from the farm of Messrs. Thomas and William Edwards, near 



Eayrstown. 



Description. — Colour, dark verdigris green; the washed grains, 

 quite small and of a very rich green. 



Composition. — In 100 parts : 



Greensand, - - . 81*59 



Clay, ... - 18-41 



Quartzose sand, - - none. 



10000 

 The proportion of potash in this marl, deduced' from that of the 

 greensand, is 9-30 per cent. 



Points south of the Rancocus. — On Haines's creek, or the main 

 south branch of the Rancocus, one mile and a half below Haines's 

 place, the banks exhibit the black micaceous and astringent clay, 

 ascertained to rest throughout a considerable area beneath the true 

 green marl. In a meadow half a mile to the north of Joseph 

 Haines's the two beds are seen in contact. 



At Charles Haines's mill, two miles below Medford, on the 

 creek, a section is seen, exhibiting on the top a greenish siliceous 

 sand ; beneath this, a gray sand some feet thick, containing a 

 small proportion of the green granules ; and under this, the straw- 

 coloured limestone two feet thick. 



These beds hold the same order, and are identical in com- 

 position with those above the green marl at New Egypt and 

 elsewhere, towards the eastern side of the " marl tract." One- 

 fourth of a mile from the mill, the beds have been cut through, in 

 digging a well, into the greensand underneath. The limestone 

 was reached between seven and eight feet below the surface. It 

 was in thin irregular beds, separated by incohering sand and 

 calcareous grains, similar to the mixture which composes the 

 rock ; its total thickness is about six feet; the organic remains are 

 the same which characterize the limestone at Vincentown. The 

 marl stratum here possesses when dry, a dark, slightly greenish- 

 gray hue, the granules being coated with a very copious efflo- 

 rescence ; it resembles the marl at Inskeep's. In the upper part of 

 the bed there is a layer four feet thick, of decomposed shells, 

 (Gryphea, &c.) mingled with the green grains, in a dark friable 



