No. 6. 



DEPARTMENT OP AGRICULTURE. 



189 



Let us note first the quantity of lime in the fine soil from the 

 respective formations and localities. The percentages ranged from 

 .08, in the "glacial loam," from Venango county, to 1.09 per cent, 

 in the Hagerstown gravelly loam from Schoeneck, Lancaster county, 

 samples. It shouM be said that most of the samples came from 

 long-cultivated fields, which had doubtless, in accordance with local 

 custom, received more or less frequent and heavy dressings of lime. 

 In the cases marked with an asterisk, white lime particles were 

 distinctly visible in the soil. In but one of these soils, the Venango 

 glacial loam (No. II) is the lime percentage so low, when considered 

 in connection with the soil texture, that the soil must be termed 

 "poor." Notwithstanding this fact, Nos, 3, 4, 10, 20, 21, 22 and 23, as 

 well as No. 11, have all proven highly responsive to liming. The 

 full functions of lime are not performed by any lime compounds save 

 the hydrate or carbonate, although the other lime-containing sub- 

 stances attacked by acid would doubtless serve in general to supply 

 to the lime needed by plant for food. Lime silicates would not be 

 so active in liberating potash, phosphoric acid or nitrogen, and prob- 

 ably would not favor the same bacteria that prosper in the presence 

 of the carbonate. In but one of the soils last named was there 

 enough carbonic acid to combine with more than one-fifth of the lime 

 present, and that soil was not directly derived from a lime- 

 stone, but was No. 11, the drift soil. In No, 23 the Cecil clay, con- 

 taining .S3 per cent, of lime, there was enough carbonate to combine 

 witli but one-twentieth of the lime dissolved out by strong acid. 



There is another fact very evident respecting the lime. It is often 

 remarked with surprise that limestone lands are capable of giving 

 profitable returns from liming. These analyses reveal the fact that 

 despite their origin they are not especially rich in lime, and that 



