I think nothing can be said more strongly to confirm the Truth of this, than what is related by the Authors quoted by Mr. Evelyn[27], to this Effect, viz.
[27]In Pag. 17, 18, and 19, of his Phil. Discourse of Earth.
‘Take of the most barren Earth you can find, pulverize it well, and expose it abroad for a Year, incessantly agitated[28]; it will become so fertile as to receive an exotic Plant from the furthest Indies; and to cause all Vegetables to prosper in the most exalted Degree, and to bear their Fruit as kindly with us as in their natural Climates.’
[28]i. e. Stirr’d often.
This artificial Dust[29], he says, will entertain Plants which refuse Dung, and other violent Applications; and that it has a more nutritive Power than any artificial Dungs or Compost whatsoever: And further, that by this Toil of pulverizing, “’tis found, that Soil may be so strangely alter’d from its former Nature, as to render the harm and most uncivil Clay[30] obsequious to the Husbandmen, and to bring forth Roots and Plants, which otherwise require the lighted and hollowest Mould[31].”
[29]Tho’ it may be impossible for the Plough to reduce the whole Staple into so fine Powder, yet the more internal Superficies it makes, the more Dust will be made by the Atmosphere in Proportion; and great Clods perhaps are of no Use to Plants, but by that Dust they let fall, being thence extricated by the insensible Ferment of the nitrous Air; and the Surfaces of this artificial Dust must receive such Operations from the Air, before the utmost Fertility be obtain’d.
[30]But I take harsh uncivil Clay to be the least profitable of any to keep in Tillage.
[31]To this Dust, Namque hoc imitamur arando ought to be apply’d, and not to Putre Solum, which itself needs Tillage, as well as strong Land: But it seems the Antients did not observe the Difference between natural Pores (or Hollowness) and artificial ones, tho’ it is very great; as is shewn in Chap. of [Pasture of Plants]: ’Tis easier indeed to imitate this artificial Dust in hollow than in strong Land.
’Tis to be suppos’d, that the Indian Plants had their due Degrees of Heat and Moisture given them; and I should not chuse to bestow this Toil upon the poorest of Earth in a Field or Garden, tho’ that be the most sure wherein to make the Experiment[32].
[32]This is the most proper Trial of the Effect of Pulveration by pounding and grinding; but Land may be so barren, that Plough or Spade may not be sufficient to pulverize it to that Degree, which is necessary to give it the same Fertility, that Pounding in a Mortar, or grinding betwixt Marbles (as Colours are ground), can.