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a dry feafon, fand is eafily mixed with them ; but clay does not mis;with fandy foils with fuch facility. This fucceeds beft when theclay is fpread on the furface, and lies till froft and rain have fepa-rated its particles. It then gradually mixes, in the courfe jf plough-ing- . . .
Irrigation, the fertilizing of land by the means of water, muft beconfidered as a fpecies of manuring obtained from the mineral king-dom, fince it is admitted that irrigation fertilizes chiefly by the mat-ter which the water brings along with it from the furface, or fromthe bowels of the earth. In fome diftri&s, the floating of arableland, while in grafs, to enrich it for a courfe of corn crops, wasmuch praftifed. Dams were made to divert the courfe of ftreams,aquedufts built to condudl the water over hollows, and trenches cutto take it through heights ; and thus a confiderable extent of fur-face was frequently overflowed. The large crops which were thusobtained awakened the avidity of farmers, who continued alternatelyto float and crop till the foil was fo much exhaufted that it-couldneither carry corn nor grafs. The praftice is therefore difcontinued.Careful hufbandmen bellow fome pains to lead the water from thehigher grounds, or from brooks which have a higher fource, overthe flat marfhy meadows, which are kept in perpetual grafs. Thefewere thought valuable pofleflions, when the culture of artificial grafswas lefs common ; but many of them have been drained of late andploughed for corn crops. Some individuals, induced by the fuccef-ful irrigation of meadows in fome Englilh counties, have begun tofollow the example. Though perhaps the fame perfection in thatart is not yet attained, nor the increafe of grafs fo confiderable, yetevident improvement has been made on meadows in different partsof the country, which will probably induce others, whofe fituationeare adapted to the purpofe, to follow the example.
Decayed Organized Bodies.
Farm dung, it is admitted on all hands, of all the fubltances ap-plied to the foil, is that on which the prefervation and advancementof the general fertility of the country principally depends. Mollof the gentlemen who have fent reports to the Board, reprobate, iaftrong terms, the negligence and inattention of farmers in the collec-tion and management of this important fubftance, and with greatjuftice ; for though the fault is not univerfal, it is but too general.It is aftonifhing to fee a man, fhrewd and fagacious, toil himfelf orfervants and horfes through ftorm and mire, labouring land for a cropwhich he knows he has already exhaufted ; or going twenty milesto a market in hope of getting a {hilling more for a horfe or cowthan he could get at home ; yet walking about his doors to his an-gles in muck, and feeing it gliding off in folution and filling everygutter, or waftied away in torrents by every (hovrer, without taking