18 AMERICAN AGRICULTURE. 



Sandy soils are improved by the frequent use of a heavy 

 roller ; it cannot be used too often. They require to be 

 made more compact, and any treatment that secures this 

 object, will be advantageous. 



Lime, by its chemical action on the constituents of soils, 

 while it separates clay, renders sand more adhesive ; and 

 when cheaply obtained, it is always a profitable dressing for 

 sandy soils, to the full amount they may require. Gypsum, 

 in considerable quantities, has an effect similar to lime, both 

 on clay and sand ; and when added in smaller portions, pro- 

 duces a striking increase in the crops of sandy soils. Clay 

 marls containing either carbonate, sulphate, or phosphate 

 of lime, are of great value to sandy soils. Equally bene- 

 iicial are ashes leached or unleached, peat, or vegetable 

 manures of any kind. Some calcareous sands, containing 

 a large proportion of lime, like those of Egypt and exten- 

 sive regions in the Barbary States, will produce luxuriantly, 

 if supplied with a slight addition of manure and an abun- 

 dance of water. Sandy soils can never be profitably culti- 

 vated till they have acquired sufficient compactness and fer- 

 tility to sustain a good growth of grass or clover ; and 

 when once brought to this condition, they are among the 

 most valuable. 



They are at all times, easily plowed and worked; they re- 

 quire no draining; and though light and dry, are quick and 

 kindly soils, giving an immediate and full return for the labor 

 and manure bestowed upon them. When in a condition to 

 produce grass, sheep are admirably adapted to preserve 

 and augment their fertility, and by their incessant migrations 

 over it, their sharp hoofs pack the surface closely, producing 

 the same effect as the roller. 



GRAVELLY SOILS, are in some respects similar to sand, but 

 much less desirable, being appropriately termed hungry. 

 They are also like the latter, peculiarly leachy, but in an 

 increased degree, permitting the rapid escape of manures 

 both by evaporation and drainage. Such as are calcareous 

 or composed of limestone pebbles, are in a great measure 

 not subject to those objections ; as the disposing affinities 

 of the lime, (of which enough will be found to exist in the 

 soil in a finely comminuted or divided state, which in this 

 condition is enabled to act efficiently,) have a tendency to re- 

 tain the vegetable matters, thus compacting the soil, and 

 holding whatever pabulum or food of plants, may from time 



