NATURE AND PROPERTy ON THE SOIL 3tJ 



observation and common practice, afford no means of ascer- 

 taining the cause, or of removing the effect. And also, when 

 it is considered that the primitive earths, clay and sand, con- 

 tain, each perhaps in nearly equal degrees, the food of plants ; 

 and that in their union, the purposes of vegetation are most 

 completelv answered. What precise quantities of each 

 maybe necessary, to make this union perfect, it is neitlier very 

 easy nor very material to ascertain, since that point is best de- 

 termined in practice, when the soil proves to be neither too 

 stiff nor adhesive from the superabundance of clay, nor of too 

 loose and weak a texture from an over quantity of sand in its 

 composition. The medium is undoubtedly best; though an 

 exc&ss towards adhesion is obviously the most safe. But when, 

 from the situation of the soil, there must necessarily be a defi- 

 ciency of either sand or clay, the most perfect remedy for that 

 deficiency, is compost manure, or decomposed animal and veg- 

 etable substances. For compost manure, whether it is made 

 up solely of these substances, or with barn dung intermixed 

 vv'ith them, is the product of all the nutritive ingredients v.-hich 

 are essential to vegetation. It is therefore the most certain 

 and durable agent in promoting fertility ; and is not only the 

 most salutary substitute for either of the primitive snnple earths, 

 bat tlie most powerful auxiliary, to render them efficacious. It 

 should be observed, that what are sometimes called gravelly 

 soils, may be distinguished from sandy soils, in this, that the 

 former is chiefiy composed of small soft stones ; though in 

 some instances, the stones are of the silicious, or flinty nature, 

 and in others, of the calcareous, or chalky. From these con- 

 stitutional circumstances, arises the propriety of deepemng 

 gravelly soils by coats of marl, or keeping them fresh by fre- 

 quent returns of grass, and repeated applications of manure. 

 Like sand, they are naturally barren, unless mixed v/ith other 

 earths; an 1 the surface would exhibit the same appearance as 

 the subsoil, or what is beyond the reach of the plough, were it 

 not changed ajid meliorated by vegetable manure. The con- 

 stitutional qualities of gravels also point out the propriety of 

 ploughing them deep, so that the surface of the soil may be 

 augmented, or rather its fertility increased, by exposing the 

 subsoil to the salutary influences of the sun and atmospheric air. 

 Although mucli more useful information might be disclose 1 on 

 this subject, yet enough has been aaid to convince the farmer, 

 that if he would render his efforts successful, he should make 

 the knowledge of the nature and properties of the soil he would 

 cultivate, a fundamental principle. 



