s, it may still be said to divide the waters, if we
understand by water not the element but formless matter. Augustine,
in fact, says (Super Gen. cont. Manich. i, 5,7) that whatever divides
bodies from bodies can be said to divide waters from waters.

If, however, we understand by the firmament that part of the air in
which the clouds are collected, then the waters above the firmament
must rather be the vapors resolved from the waters which are raised
above a part of the atmosphere, and from which the rain falls. But to
say, as some writers alluded to by Augustine (Gen. ad lit. ii, 4),
that waters resolved into vapor may be lifted above the starry
heaven, is a mere absurdity. The solid nature of the firmament, the
intervening region of fire, wherein all vapor must be consumed, the
tendency in light and rarefied bodies to drift to one spot beneath the
vault of the moon, as well as the fact that vapors are perceived not
to rise even to the tops of the higher mountains, all to go to show
the impossibility of this. Nor is it less absurd to say, in support of
this opinion, that bodies may be rarefied infinitely, since natural
bodies cannot be infinitely rarefied or divided, but up to a certain
point only.

Reply Obj. 1: Some have attempted to solve this difficulty by
supposing that in spite of the natural gravity of water, it is kept in
its place above the firmament by the Divine power. Augustine (Gen. ad
lit. ii, 1), however will not admit this solution, but says "It is our
business here to inquire how God has constituted the natures of His
creatures, not how far it may have pleased Him to work on them by way
of miracle." We leave this view, then, and answer that according to
the last two opinions on the firmament and the waters the solution
appears from what has been said. According to the first opinion, an
order of the elements must be supposed different from that given by
Aristotle, that is to say, that the waters surrounding the earth are
of a dense consistency, and those around the firmament of a rarer
consistency, in proportion to the respective density of the earth
and of the heaven.

Or by the water, as stated, we may understand the matter of bodies to
be signified.

Reply Obj. 2: The solution is clear from what has been said,
according to the last two opinions. But according to the first
opinion, Basil gives two replies (Hom. iii in Hexaem.). He answers
first, that a body seen as concave beneath need not neces