248 [Senate 



the subsoil is hard and impermeable, showing the benefit of deep and 

 thorough plowing. In either case, however, as the supply begins to 

 fail, and the soil grows drier, its finer parts absorb moisture from the 

 air; and the plants are constantly nourished by this invisible fountain. 



But the different constituent parts of the soil, act with different 

 degrees of energy.* Of the earths, the silicious is the weakest, and 

 the aluminous the strongest, while lime holds an intermediate posi- 

 tion. Not one of these however would do by itself. We want sand, 

 because no soil consisting entirely of impalpable matters, is fertile;! 

 and we want it to keep the soil loose, so that the air can enter its 

 pores, and give up the water which it holds as vapor. Without 

 such assistance, stiff clay or aluminous earth would absorb but little- 

 moisture from the atmosphere, because it cakes and shuts out the air. 

 Lime is also a valuable auxiliary in rendering the soil more absorbent, 

 independent of its other indispensable qualities. 



But the soil, however it may be tempered and constituted, can 

 never be absorbent in a high degree without culture. Some crops 

 indeed require more of this quality than others. Thus Indian corn 

 requires more than wheat; and wheat more than the grasses of 

 the meadow. But vegetable and animal matters are more absorbent 

 than the earths; and culture only can properly introduce them into 

 the soil. Even when there, frequent stirring is necessary to keep 

 the ground loose and the pores open, for the free admission of the 

 air and the easy passage of the roots. 



Our coats sometimes become spotted with mud. We apply the 

 brush, but-the bristles pass over without effecting its removal. What 

 is the reason ? The clay which was suspended in the water, forms 

 a glaze or crust. It is just so with the interior of a soil which has 

 laid long unstirred. The clay forms a crust round the inside of all 

 the little cavities, preventing the free circulation of air, and the in- 

 troduction of moist vapor. The fertilizing principles are excluded. 



The celebrated Tull, observing the extraordinary effects of high 

 culture, concluded that plants fed on mellow earth, and Duhamel 

 adopted the same notion. Their philosophy was coarse^ but their 

 practice was fine. If we were to follow their example, making 

 plenty of fine earth for the plants — not to feed on, but to drink from, 

 our crops might be greatly increased. One of the chief errors of 

 our husbandry is to cultivate too much land, because it is only half 

 done. Half the quantity with double the work on it, and double 

 crops would be found more profitable. 



I have long believed, however, that no part of the system re- 

 quired reformation more than our management of manures. Manure 

 has been called the wealth of the farmer. When it is taken out in 

 the spring, it is commonly scattered over the ground in large lumps; 

 the plow comes along and covers them or not, as the case may be. 

 If covered, they intercept the ascent of the moisture from below, 

 especially in dry seasons. If not covered, they lie wasting on the 



* Davy's Agricultural Chemistry. 



t " Sand gives little absorbent power."— Agric. Chemistry. "Sand is incapable of absorbing 

 moisture from the atmosphere, or of retaining any valuable vapor or fluid." — Essay on Calcare- 

 ous Manures. 



