NORTH-CAROLINA GEOLOGICAL SURVEY. 23 



like all vegetable soils. It is not however spongy. Bains do 

 not expose grains of quartz as in many instances of the gall- 

 berry lands. It becomes rather lumpy on drying. Its com- 

 position is as follows : 



Organic matter, 48.10 



Silex: 43.00 



Oxide of iron and alumina, 6.40 



Lime, 0.21 



Magnesia, 012 



Potash 0.16 



Soda, 0.18 



Chlorine, trace, 



Soluble Silex, 0.03 



Sulphuric acid, 0.04 



Phosphoric acid, 0.30 



98.55 



The silex, after the removal of the organic matter, is of a 

 light drab color, exceedingly fine, or nearly fine enough for 

 sharpening fine edge tools. If all the vegetable matter was 

 removed, this fine earth would probably be too compact and 

 close for cultivation ; but, intermixed as it is with the debris 

 of vegetables, it is sufficiently porous to admit all the light 

 and air required for the luxuriant growth of any crop which 

 may be put upon it. 



The composition of this soil, it is evident, shows a large 

 proportion of vegetable matter. This is intimately blended 

 with fine earthy matter, the basis of which is silex. In com- 

 bination with it we find a full pioportion of iron and alumina, 

 or clay, which gives coherency to the grains, and besides the 

 nutritive elements, lime, magnesia, potash, phosphoric acid, 

 exist in as large proportions as in other rich and productive 

 soils. The regular yield of this soil to the acre is from ten 

 to twelve barrels of Indian corn. In favorable seasons it 

 amounts to twelve, in less favorable it may reach only ten 

 barrels. It is -also easy to cultivate. 



The composition of a soil of a similar character, and which 

 has been under culture by Mr. Burroughs, of the north side 

 of the lake, is as follows : 



