296 Geological Report in Relation to- the S'-ils of Kentuchy. [July 



In communicating the result of this analysis, Dr. Peter remarks 

 with great justice : 



" Notwithstanding the luxuriance of the growth of the first crops 

 on the prairie soil, occasioned partly by the large amount of availa- 

 ble nourishing matter aflforded by the decay of the thick sod, it is 

 evident from the above analysis, that, taking into consideration dur- 

 ability as well as immediate fertility^ as ascertained by the chemical 

 analysis of the soil itself, apart from the sod, there are many of our 

 Kentucky soils which take the second rank, when compared with 

 those of the hlue grass region, which yet are fully equal to this prairie 

 soil. 



Compared with the first-rate soils of Kentucky, that of the 

 prairies contains a much smaller proportion of alumina and oxide 

 of iron, as well as lime, magnesia, phosphoric acid and alkalies. It 

 contains a much larger proportion of fine sand and doubtless a lar- 

 ger proportion of the coarser sand than our best soils ; and, there- 

 fore, while its large quantity of organic matters is held in the soil 

 with a small force of attraction, because of the large proportion 

 which the sand and silica bears to the alumina and oxide of iron ; 

 and hence they are readily soluble and immediately available in the 

 production of luxuriant crops ; these very circumstances will cause 

 its more speedy exhaustion ; and when the accumulated store of 

 organic matter has been consumed by thriftless husbandry, soil can 

 not rank beyond a second rate position. 



By a comparison of the constituents of this Illinois prairie soil 

 with the average soils of Kentucky, for example with (a) of the 

 following table, which is an upland soil of Franklin county, waters 

 of Benson, near Ilardinsville, and (b) a sub-carboniferous soil of 

 the Barren limestone formation. Barren county, we perceive that 

 these Kentucky soils are, as a whole, in no ways inferior. 



Organic and volatile matter 9,133 5,200 

 Alumina only in (b), alumina including oxide of iron 



and magnese (a) 3,1000 8,460 



Oxide of iron - 2'206 



Carbonate of lime ....-- ,316 ,306 



Carbonate of magnesia in (a), magnesia alone in (b) ,517 ,205 



Brown oxide of manganese ----- ,234 



Phosphoric acid ,243 ,159 



Sulphuric acid --...-- ,008 



Potash ,173 ,197 



