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the fermentation is moderate, and the emission of carbonic acidgas inconsiderable: but these volatilizable principles are at lengthdisengaged and dissipated in air by a continued fermentation.Mr Young, the diligent experimenter above cited, submitteddifferent substances, in a retort, to a red heat, and received thegases which came from them: from an ounce of the new fallenexcrements of domestic animals 98 measures *f gas, at an aver-age, was emitted ; and still more from an ounce of fresh straw:From an ounce of the excrements and litter of a new dunghill, 88measures ; but from an ounce of that which had been turned andfermented for a year, only 38| measures. Thus a rapid fermen-tation, and the long continuance, appears, in every light, to bsattended with very great waste.
But, though it were possible, by the means of fermentationaccelerated or long continued, to render this composite mass allat once capable of solution, before it were committed to the soil,without the great waste which we have been considering, the ge-neral fertility of the country would not thereby be advanced, butinjured. Cultivated plants would either be pushed up with un-productive luxuriance, the first year, leaving little aliment forthose of the ensuing ; or, if the solution were in great excess, ve-getation would be suffocated: for even the most nutritious ali-ment proves poisonous, when in excess. Three peas were steep-ed, for 24 hours, in a tea cupful of strong dung juice, and threein plain water: each three were planted, half an inch deep, inseparate flower-pots filled with garden mould, and the liquid inwhich they had been steeped poured into the pots over them.Those which had been steeped in plain water appeared aboveground 30 hours before the others. Both advanced; but thosein the dung juice had the most weakly appearance. When theplants were about four inches high, the lower leaves of those fedby the dung juice wallowed and fell off; and in about four weeksafter the plants died, though they were daily watered, while thoseto which water only had been administered, continued healthy.Thus it appears that an excess of the most nutritious solution isprejudicial to vegetation, particularly in its early stages ; apd itwould appear, upon the whole, that to restrain the fermentation ofthe mass, by laying it compact, and filling the interstices witha. sufficient proportion of water to keep it soft and disposed tosolution, and mixing it with the soil before it be wholly decom-posed, is in every respect most advantageous. It then yields itssolution slowly, and in proportion to the, demand of the plantswhich are meant to be cultivated.
As the general fertility of a country, other circumstances cor-responding, must always be greater in proportion to the abun-dance of organized spoils, in a soluble state, with which its soilis stored, it must certainly be of the highest importance to knowShow the greatest quantity of this valuable substance may be oh-