524 Of Vegetation, 
with proper inftruments to fuck it thence. 
But the leaves feem alfo deligned for many 
other noble and important fcrvices j for 
nature admirably adapts her inftruments fo 
as to be at the fame time ferviceable to 
many good purpofes. Thus the leaves, in 
which are the main excretory dufts in vege- 
tables, feparate and 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 nourifhment, we 
have good reafon to think, is conveyed into 
vegetables thro* the leaves, which do plenti- 
fully imbibe the Dew and Rain, which con- 
tain Salt, Sulphur, 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 conftantly forming in the 
air, are doubtlefs very ferviceable, in promo- 
ting the work of vegetation 5 when being 
imbibed by the leaves, they may not im- 
probably be the materials out of which the 
more 
