NORTH-CAROLINA GEOLOGICAL SURVEY. 51 



Silex, 88.700 



Peroxide of iron and alumina, 3.350 



Lime, 0.100 



Magnesia 0.022 



Sulphuric acid, 0.010 



Chlorine, trace, 



Potash, 0.048 



Soda, 0.010 



Organic matter, 1 .800 



Water, 5.000 



99,040 



This specimen of soil has a better composition than either 

 of the four of this lot. There is less silica, more lime and 

 potash ; though the amount of organic matter and peroxide 

 of iron and alumina is still comparatively small, and we infer 

 from that fact, that the amount of phosphates is also small. 



This soil has no doubt been under cultivation for years. It 

 has a good basis to build upon, as the silex is fine and not 

 very excessive in quantity. It is evidently a better soil than 

 No. 1, and does not rank in the class with No. 2, which is a 

 coarse clayey silicious soil, the particles of which are very 

 coarse. In all these samples the cultivation should not be 

 carried to that extent which would effect an entire exhaus 

 tion. 



The remarks upon the four foregoing soils have been sug 

 gested by the analyses and their physical properties. No 

 information has been obtained respecting the treatment to 

 which they have been subjected. 



28. A soil of a somewhat remarkable appearance, and 

 having a good composition, is spread over large portions of 

 the eastern counties. It is not always a surface soil ; indeed 

 it is rather rare to meet with it under cultivation. It occupies 

 a distinct position in the series of soils, and is really one of 

 the deposits which is always associated with the marl beds. 

 It cannot, with propriety, be regarded as a marl, though 

 under favorable circumstances it may be used as a fertilizer. 



It has a brown color, and when wet is as tenacious as the 

 ordinary clays, though it has less alumina in its composition ; 

 it is very adhesive to the shoe or boot, and if it is ever profit- 



