The Ignorance of this seems to be one principal Cause, that Agriculture, the most necessary of all Arts, has been treated of by Authors more superficially than any other Art whatever. The Food or Pabulum of Plants being prov’d to be Earth, where and whence[9] they take that, may properly be called their Pasture.
[9]By the Pasture is not meant the Pabulum itself; but the Superficies from whence the Pabulum is taken by Roots.
This Pasture I shall endeavour to describe.
’Tis the inner or (internal) Superficies[10] of the Earth; or which is the same thing, ’tis the Superficies of the Pores, Cavities, or Interstices of the divided Parts of the Earth, which are of two Sorts, viz. Natural and Artificial.
[10]This Pasture of Plants never having been mentioned or described by any Author that I know of, I am at a loss to find any other Term to describe it by, that may be synonymous, or equipollent to it: Therefore, for want of a better, I call it the inner, or internal Superficies of the Earth, to distinguish it from the outer or external Superficies, or Surface, whereon we tread.
Inner or internal Superficies may be thought an absurd Expression, the Adjective expressing something within, and the Substantive seeming to express only what is without it; and indeed the Sense of the Expression is so; for the Vegetable Pasture is within the Earth, but without (or on the Outsides of) the divided Parts of the Earth.
And, besides, Superficies must be joined with the Adjective Inner (or Internal) when ’tis used to describe the Inside of a thing that is hollow, as the Pores and Interstices of the Earth are.
The Superficies, which is the Pasture of Plants, is not a bare Mathematical Superficies; for that is only imaginary.
By Nature, the whole Earth (or Soil) is composed of Parts; and, if these had been in every Place absolutely joined, it would have been without Interstices or Pores, and would have had no internal Superficies, or Pasture for Plants: but since it is not so strictly dense[11], there must be Interstices at all those Places where the Parts remain separate and divided.
[11]For were the Soil as dense as Glass, the Roots or Vegetables (such as our Earth produces) would never be able to enter its Pores.