3 T4 Anatyfis of the Air. 
fore be fooneft changed from an elaftick 
to a fixt ftate. And 'tis confonant to reafon 
to think, that the air may confift of infinite 
degrees of thefe, from the mod elaftick and 
repelling, till we come to the more {luggifti, 
watry and other particles, which float in 
the air ; yet the repelling force of the leaft 
elaftick particle, near the furface of the earth 
while it continues in that elaftick ftate, mud 
be fuperior to the incumbent preflfure of a 
column of air, whole height is equal to that 
of the atmofphere, and its bafe to the fur- 
face of the fphere of its elaftick adivity. 
Thus upon the whole, we fee that air a- 
bounds in animal, vegetable and mineral fub- 
dances 5 in all which it bears a confiderable 
part; if all the parts of matter were only 
endued with a ftrongly attrading power, 
whole nature would then immediately be- 
come one unadive cohering lump ; where- 
fore it was abftolutely neceflary, in order to 
the aduating and enlivening this vaft mafs of 
attrading matter, that there fhould be every 
where intermixed with it a due proportion 
of ftrongly repelling elaftick particles, which 
might enliven the whole mafs, by the in« 
ceffant adion between them and the at- 
trading particles : And fince thefe elaftick 
pat- 
