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If these are admitted to be founded in truth, they may serve tocorrect some erroneous opinions held concerning this substance,and to direct how it may be most advantageously prepared andapplied. From the doctrine contained in these aphorisms, welearn, that some of the component parts submit to putrefactionmore quickly than others ; and that those which are becomeputrid, when they come in contact with those still resisting,facilitate the putrefaction of the latter—Hence all the ingredi-ents should be mixed, and spread over one another in regularstrata, so as to come in mutual contact.
That when the mixed ingredients are surrounded with putridwater, they gradually putrefy, dissolve, and are diffused in it,with little waste, and that putrefaction goes on without ceasing
so long as they are kept moist_Hence the mass should be so
much compressed as not to leave vacuities among its parts; sup-plied with water sufficient to fill the smaller interstices; and keptlevel on the surface, that all parts may be equally wet.
That when putrefaction has commenced in these wet substan-ces, surface mould facilitates the final decomposition, eagerly ab-sorbs and retains the essence, allowing only the superfluous waterto escape. This is proved by ocular inspection of soils whichhave been long and much dunged, where the stirred soil is of adark colour, and what is immediately under it retains its originalhue.—Hence there appears no necessity for continuing this sub-stance under preparation, till it be reduced to its first principles ,by which are lost the gases which escape in the preparation, andthe gentle heat ■which the latter fermentation excites in the soil.
That when the substances in question, or their solution, are ex-posed to evaporation, water only escapes, leaving the substancesessentially the same as before; but by long exposure to light andair, the undissolved part alters its colour, hardens, and becomesmore difficult of solution_Hence there is no cause for the ap-
prehension which so generally prevails of dung being robbed, byevaporation, of its essence, its oils, its salts, and all these finethings; but nevertheless it is prudent to turn it, with all its mois-ture about it, quickly into the soil, and not suffer it to remain ina situation in which its solubility is injured.
Upon the whole, from any thing yet known, it appears thatfarm dung is most economically prepared by being macerated ina wet dung-stead, and may be safely carried to the field at anyperiod, when the land is in order for having it quickly ploughedm - But if there should still be a necessity for carrying it out atany other period, a quantity of mould should be provided, withpart of which a base should be formed of at least 8 or 9 inchesthick on which to build the heap of dung ; and as soon as theheap is finished, the rest should be clapped around and over it°f equal thickness: Where peat moss is at command, it is veryproper for this purpose. In this manner, though the bulk will -dh? diminished, a good part of the essence will be preserved.