EARTHS AND SOILS. 41 



sand ; sandy or gravelly soils that effervesce with acids, 

 should be distinguished by the names of calcareous sands, 

 or calcareous gravels, to distinguish them from those that 

 are silicious. The term clayey soil should not be ap- 

 plied to any land that contains less than one sixth of im- 

 palpable matter, not considerably effervescing with acids ; 

 the word loam should be limited to soils containing at 

 least one third of impalpable earthy matter, copiously 

 effervescing with acids. A soil, to be considered as 

 peaty, ought at least to contain one half of vegetable mat- 

 ter. In cases where the earthy parts of a soil evidently 

 consist of the decomposed matter of one particular rock, 

 a name derived from the rock may with propriety be 

 applied to it. Thus if a fine red earth be found immedi- 

 ately above decomposing basalt, it may be denominated 

 basaltic soil. If fragments of quartz and mica be found 

 abundant in the materials of the soil, which is often the 

 case, it may be denominated granitic soil ; and the same 

 principles may be applied to other hke instances. In gen- 

 eral, the soils, the materials of which are the most vari- 

 ous and heterogeneous, are those called alluvial, or which 

 have been formed from the depositions of rivers ; and these 

 deposits may be denominated silicious, calcareous, or ar- 

 gillaceous ; and in some cases the term salinic may be 

 added as a specific distinction, applicable, for example, 

 at the embouchure of rivers, where their alluvial remains 

 are overflowed by the sea. Such are some of the rules 

 for classifying soils laid down by Loudon, in his Encyclo- 

 pedia of Agriculture. 



We occupy a soil which may be strictly denominated 

 a sandy one. We have dressed some of it with blue clay, 

 containing from twenty-five to thirty per cent, of carbonate 

 of hme, say at the rate of from twenty to thirty loads to 

 an acre, and we are continuing the practice ; being per- 

 suaded, from philosophy, as well as experience, that a 

 load of blue clay is ultimately of more benefit to our soil 

 than a load of barn-yard manure. 



In the application of clays, or clay marl, and most clays 

 contain a portion of carbonate of lime, " the great point 

 to be obtained," says Professor Emmons, in his Geologi- 

 4# 



