Chap. III. Of Pasture of Plants. 23 



'Tis the inner or (internal) Superficies (a) of the 

 Earth ; or which is the fame thing, 'tis the Superficies 

 of the Pores, Cavities, or Interftices of the divided 

 Parts of the Earth, which are of two Sorts, viz. 

 Natural and Artificial. 



By Nature, the whole Earth (or Soil) is compofed 

 of Parts ; and, if thefehad been in every Place abso- 

 lutely joined, it would have been without Interftices 

 or Pores, and would have had no internal Superficies, 

 or Pafture for Plants : but fince it is not fo ftri&ly 

 denfe (£), there inuft be Interftices at all thofe Pla- 

 ces where the Parts remain feparate and divided. 



Thefe Interftices, by their Number and Largenefs, 

 determine the fpecific Gravity (or true Quantity) of 

 every Soil: The larger they are, the lighter is the 

 Soil ; and the inner Superficies is commonly the lefs. 

 . The Mouths, or Latteals, being fituate, and open- 

 ing, in the convex Superficies of PvOots, they take 

 their Pabulum, being fine Particles of Earth, from 

 the Superficies of the Pores, or Cavities, wherein the 

 Roots are included. 



(a) This Pafture of Plants never having been mentioned or 

 described by any Author that I know of, I am at a lofs to find 

 any other Term to defcribe it by, that may be fynonymous, or 

 equipollent to it : Therefore, for want of a better, I call it the 

 inner, or internal Superficies of the Earth, to diftiriguifh it from 

 the outer or external Superficies, or Surface, whereon we tread. 



Inner or internal Superficies may be thought an abfurd Ex- 

 preftion, the Adjective exprefling fomething within, and the Stib- 

 ftantive feeming to exprefs only what is without it; and indeed 

 the Senfe of the Expreflion is fo ; for the Vegetable Failure is 

 within the Earth, but without (or on the Outfides of) the divided 

 Parts of the Earth. 



And, beiides, Superficies muftbe joined with the Adjeclive In- 

 aer (or Internal) when 'tis ufed to defcribe the Infide of a thing 

 that is hollow, as the Pores and interftices of the Earth are. 



The Superficies, which is the Pafture of Plants, is not a bare 

 Mathematical Superficies; for that is only imaginary. 



{b) For were the Soil as denfe as Glafs, the Roots or Vege- 

 tables (fuch as our Earth produces) would never be able to enter 

 its Pores. 



C 4 And' 



