[ ex Fj 
not grow and thrive, as they did 
“‘moit remarkably in my firft ex- 
** periments at Leeds, the reafon of 
*‘ which I cannot difcover.—In 
‘¢ thofe inftances in which the plants 
*¢ grew the beit, they were, how=- 
** ever, but fickly,as appeared by the 
«¢ Jeaves loos turning yellow, and 
‘¢ falling off when the leaft motion 
se was given to them. In fome 
i cafes,. neeeues as in thofe men- 
“* tioned in vol. I. p. 91, I faw no 
© particular reafon why the air 
_ * fhould not have been meliorated. 
Be Lpon Bhe whole, I {till think 
© it probable;—that. the, vegetation 
Sof healthy plants, growing in fi- 
“ tuations natural to them, has-a_ 
 fahutary eficct on the air in which 
«“ “they grow. For one clear in- 
fiance of the melioration of air in 
_ thefe circumftances fhould weigh 
ae as againit 
cote ay ee ee , = : g . 
2 se Seen eee se abe . os s ‘ 
i ee ee ee ee 
¥ - 
Siac oh tee yas oe oe ees 
Se ee EN a ee 
