KICK EIVER AND LIME-STONE SOILS. 63 



2. Black silicious loam from the celebrated lands on Back river, 

 near Hampton. 



3. Soil from rich land on Pocoson-river, York county. 



4. Black clay vegetable soil, from a freSh-water tide marsh on 

 James river formed by recent alluvion. 



5. Alluvial soil of first-rate fertility above the falls of James 

 river dark brown clay loam, from the valuable and extensive 

 body of bottom land belonging to General J. H. Cocke, of Flu- 

 vanna. 



The most remarkable facts of the absence of calcareous earth 

 are to be found in the lime-stone soils, between the Blue Ridge 

 and Alleghany Mountains. Of these, I will report all that I have 

 examined ; and none contained any calcareous earth, unless when 

 the contrary will be stated. 



Before the first of these trials was made, I supposed (as proba- 

 bly most other persons do) that lime-stone soil was necessarily 

 calcareous, and in a high degree. It is difficult to get rid of this 

 impression entirely and it may seem a contradiction in terms to 

 say that a lime-stone soil is not calcareous. This I cannot avoid. 

 I must take the term lime-stone soil as custom has already fixed it. 

 But it should not be extended to any soils except those which are 

 so near to lime-stone rock, as in some measure to be thereby affected 

 in their qualities and value. 



1 to 6. Lime-stone soils selected in the* neighbourhood of Lex- 

 ington, Virginia, by Professor Graham, with the view of enabling 

 me to investigate this subject. All the specimens were from first- 

 rate soils, except one, which was from land of inferior value. One 

 of the specimens, Mr. Graham's description stated to be " taken 

 from a piece of land so rocky [with lime-stone] as to be unfit for 

 cultivation, at least with the plough. I could scarcely select a 

 specimen which I would expect to be more strongly impregnated 

 with calcareous earth." This specimen, by two separate trials, 

 yielded only one grain of calcareous earth, from one thousand of 

 soil. The other five soils contained none. The same result was 

 obtained from 



7. A specimen of afluvial land on North river, near Lexington. 



8. Brown loam from the Sweet Spring valley, remarkable for its 

 extraordinary productiveness and durability. It is of alluvial for- 

 mation, and before it was drained, must have been often covered 

 and saturated by the Sweet Spring and other mineral waters, which 

 hold lime in solution. [The carbonate of lime dissolved in these 

 waters is so abundant, and so readily parted "with, that it is depo- 

 sited on every twig that is exposed therein, forming rapidly grow- 

 ing incrustations.] The surrounding high land is of lime-stone 

 soil. Of this specimen, taken from about two hundred yards be- 

 low .the Sweet Spring, from land long cultivated every year, three 



