AGRICULTURAL TEXT-BOOK. 



Thus, manures which are rich in nitrogen (ammonia,) not only 

 increase the crop, but also produce a grain richer in gluten, and 

 therefore intrinsically more valuable. On ten patches, each one 

 hundred square feet, of the same soil (a sandy loam,) manured 

 with equal weights of different manures in the dry state, 

 Hermbstadt sowed equal quantities ( Ib.) of the same wheat, 

 collected, weighed, and analyzed the produce. His results are 

 represented in the following table : 



It must not, however, be forgotten, that these are garden ex 

 periments ; and while the theory is probably quite true, in field 

 culture the farmer may be unable to produce exactly the same 

 results. Such experiments must be considered rather as illus 

 trating a general principle, than as positively useful in practice, 

 except to a limited extent. 



178. The only mode in which a farmer can judiciously use 

 manure, is by having an analysis of his land, showing what con 

 stituents are soluble, what may easily be rendered so, and what 

 is wanting. 



179. In many parts of the United States, wheat soils are manured by 

 the complex action of closer, plaster (sulphate of lime) and sheep dung 

 The philosophy of this is as follows: The surface soil is naturally, or 



