Of Ve fetation . 325 
more fubtile and refined principles of ve- 
getables are formed : For fo fine a fluid as 
the air feems to be a more proper medium, 
wherein to prepare and combine the more 
exalted principle of vegetables, than thegrof- 
fer watry fluid of the fap 5 and for the fame 
reafon, 'tis likely, that the moft refined and 
a£l:ive principles of animals are alfo prepared 
in the air, and thence conveyed thro" the 
lungs into the blood 5 and that there is plenty 
of thefe fulphurco-aereal particles in the 
leaves, is evident from the fulphureous exu- 
dations, which are found at the edges of 
leaves, which Bees are obferved to make 
their waxen cells of, as well as of the dull 
of flowers : And that wax abounds with ful- 
phur is plain from its burning freely, 
We may therefore reafonably conclude, 
that one great ufe of leaves is what has 
been long fufpefted by many, viz,, to per- 
form in fome meafure the fame office for 
the fupport of the vegetable life, that the 
lungs of animals do, fOr the fupport of the 
animal life 5 Plants very probably drawing 
thro' their leaves fome part of their nou- 
riftment from the air. 
Y 3 But 
