A 



TREATISE 



O N 



VEGETATI 



Wc. 



THE mofl: natural Introdu6i:ion to a work of this 

 kind, before we enter into particulars, is tp confi- 

 der the nature and qualities of Comports; that is, the 

 meliorations neceflary for different foils, in order to bring 

 the various plants we intend to raife, to their grcateft 

 perfefiion. 



Eariby according to the definition of the learned Boer- 

 haavey is a foffile body, neither dilToluble by fire, water, 

 or air: it is infipid, more fufible than ftone. Hill fria- 

 ble, and ufualjy containing a fhare of fatnefs in it, 



Mr. Boyle fays there is no fuch thing as a flridly fim.- 

 ple Earth; and it doth not appear that nature, any more 

 than art, affords an elementary Earth ; thofe even of the 

 fimpleft forts, having been found, upon examination, to 

 have qualities not afcribed to pure Earth. 



Earths are of many and various qualities. Some are 

 fimple and immutable ; fuch as Chalk, Pumice, and 



Rotten Stone. Others are compound and fatty; 



of which kind are the crumbly red, white, and 

 brown coloured Earth, Fuller's Earth, and divers kinds 

 of Medicinal Earths, fuch as the Terra Creticat Hun- 

 garicat Leninica, i^c. which Earths are all refolvabic- into 

 oil, a little acid fait, and a Calx, which is the bafis, or 

 Earth, properly fo called. 



Sand, 



