86 THE SOIL. 



It not unfrequently happens that an abundance of clay 

 is to be found lying underneath the sand at no great dis 

 tance below the surface. .When this is the case, clay is 

 to be dug up and allowed to remain in small ridges, so as 

 to be exposed to the sunlight, the air, the rain, and the 

 cold of winter. After having been so exposed, for a year 

 or longer, it is ready to be scattered upon the surface of 

 the sandy land, or to be ploughed into it. The good 

 qualities of the land will thus be permanently improved. 

 It will be able to absorb and will become retentive of 

 moisture, carbonic acid, and ammonia, and of all the 

 manures. Such an addition may be called an amend 

 ment. 



293. Another, and, after the clay, a still more effectual 

 way of rendering a sandy soil fertile, is the application of 

 large quantities of marsh mud, peat or swamp muck. 

 There are often, in the immediate neighborhood of sandy 

 fields, old mud holes, bogs, or swamps, where vegetable 

 substance, humus, hasbeen accumulating for centuries. 

 This, by itself, is of no value. But when spread upon 

 the land, and acted upon by the atmosphere, it immedi 

 ately begins to act upon the silicates. 



&quot; The very act of exposure of this swamp muck has. 

 caused an evolution of carbonic acid gas. Tliat decom 

 poses the silicates of potash in the sand ; that potash con 

 verts the insoluble into soluble manure, and lo ! a crop. 

 That growing crop adds its power to the geine.&quot; 



By such processes, repeated from year to year, &quot; it is 

 not to be doubted, that every inch of every sandy knoll, 

 on every farm, may be changed into a soil, in thirteen 

 years, of half that number of inches of good mould. &quot;* 



* Dana s Muck Manual. 



