Of Vegetation. 52 j 
But the leaves feem alfo defigned for many 
other noble and important fervices; for 
nature admirably adapts her inftruments fo 
as to be at the fame time fervieeable to 
many good purpofes. Thus the leaves, in 
which are the main excretory duds in vege- 
tables, feparateand carry off the redundant 
watry fluid, which by being long detained, 
would turn rancid and prejudicious to the 
plant, leaving the more nutritive parts to 
coalefce* part of which nourifliment, we 
have good reafon to think, is conveyed into 
vegetables thro 5 the leaves, which do plenti- 
fully imbibe the Dew and Rain, which con- 
tain Salt, Sulphur, &c. For the air is full 
of acid and fulphureous particles, which 
when they abound much, do by the adion 
and re-adion between them and the elaftick 
air caufe that fultry heat, which- ufually 
ends in lightning and thunder : And thefe 
new combinations of air, fulphur and acid 
fpirit, which are constantly forming in the 
air, are doubtlefs very fervieeable, in pro- 
moting the work of vegetation $ when being 
fmbibed by the leaves, they may not im- 
probably be the materials out of which the 
more fubtile and refined principles of ve- 
getables are formed : For fo fine a fluid as 
Y 3 Ac 
