3 id Of Vegetation. 
the air feems to be a more proper medium^ 
wherein to prepare and combine the more 
exalted principles of vegetables, than the grof- 
fer watry fluid of the fap 5 and for the fame 
reafon, 'tis likely, that the moft refined and 
active principles of animals are alfo prepared 
in the air, and thence conveyed thro* the 
lungs into the blood ; and that there is plenty 
of thefe fulphureo-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 fulphur is plain from its burning 
freely, &c. 
We may therefore reafonably conclude, 
that one great ufe of leaves is what has 
been long fufpe&ed 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 ; Plants very probably drawing 
thro* their leaves fome part of their non- 
rifhment from the air. 
But as plants have not a dilating and com 
trading Thorax, their infpirations and expi- 
rations will not be fo frequent as thofe of 
Ani- 
