[ xliii ] 



in a work upon fuch important 

 matter. Whatever I have been 

 able to deduce from my labours is 

 done in a hafty manner, as my 

 ftay in this country was far too 

 limited to allow me to compofe 

 my work in a regular and more 

 fatisfactory manner. 



Though I was very far from 

 forefeeing all the difcoveries which 

 I made in the courfe of this fum? 

 mer, yet I was perfuaded that a 

 good deal of the ©economy of the 

 vegetable kingdom might be dis- 

 covered by a Iteady purfuit of ex- 

 periments tending tp trace the ope- 

 rations of Nature. I had this ob- 

 ject in view fome years ago ; but, 

 as I did not enjoy fuch a favour- 

 able difpoiition of mind and body 

 ^as was necefFary for a talk, in 

 which all poilible fteadinefs, perfe- 



verance* 



