320
Before quitting this topic, it is hoped it will not be thought tin,pertinent again to recommend the regular spreading and carefuldivision of the clots of dung, so that the soil and the manure maycome more in mutual contact. The difference of effect betweenthis and the clumsy manner in which the same business is some-times performed, will be found not less than a tenth of the whole,and well worth the attention of every prudent husbandman : noris it less worthy of attention, to plough in manure with an ebbfurrow, so as to be near the surface, within reach of the tempe-rature of the atmosphere and the roots of plants.
Well digested earthy composts may be exposed on the surfacewith still greater safety, than town dung. The organized sub-stances being decomposed, and the solution absorbed by theearths, it is retained there in readiness for the nourishment ofplants, wherever it is applied. These composts are thereforewell suited for spreading on the surface, to promote the growthof the present crop, commonly called top-dressing; and will befound beneficial for that purpose, wherever the practice is con-venient or practicable. I'hey are with equal propriety spreadon the surface of p isture grounds, and either promote thegrowth of herbage, or of corn crops, when ploughed in : andthey have the additional advantage, that they somewhat increasethe thickness of thin soils.
Among the various purposes for which the earths or earthycomposts may be successfully applied, is that of amending theconstruction of barren soils. Thin, ill constructed soils, on animpervious bottom, are more permanently amended by a closecovering lying over the surface, than by the most operose exer-cise of the plough. By the former the soil is thickened, an in-creased growth of herbage is excited, the soil is defended fromdie storm, the subterraneous heat is retained, and a mellownessis gradually operated, which, under good husbandry afterwards,will long continue. Whereas, after mechanical pulverization,the particles of such soils often coalesce more firmly than be-fore. Hence it may sometimes be prudent to resort to the influ-ences of Nature in aid of human industry.
Hitherto the consistence of the soil only has been adverted to;but, for the purpose of abundant vegetation, it is requisite that itbe of the same consistence for a sufficient depth, not only to giveample range to the roots of cultivated plants, but to retain asufficient store of water in a proper state for supporting them,in a dry time, and allowing the excess to pass downwards in awet time. When the soil is thin, and the bottom so impervious asneither to suffer water to rise in exhalation during the scorchingdrought of summer, nor to descend in great rains, the crop isapt to suffer from the one extreme or the other, and is seldomplentiful. Even where Nature has been bountiful in giving am-ple depth to the soil, if that gift has been long despised, and thesurface stirred only with a superficial scraping, the unstirred