4.  “And God said, let there be a firmament in the midst of the waters, and let it divide the waters from the waters.  And God made the firmament, and divided the waters which were under the firmament from the waters which were above the firmament.” Gen. i. 6, 7.  Before laying hold of the meaning of Scripture let us try to meet objections from other quarters.  We are asked how, if the firmament is a spherical body, as it appears to the eye, its convex circumference can contain the water which flows and circulates in higher regions?  What shall we answer?  One thing only:  because the interior of a body presents a perfect concavity it does not necessarily follow that its exterior surface is spherical and smoothly rounded.  Look at the stone vaults of baths, and the structure of buildings of cave form; the dome, which forms the interior, does not prevent the roof from having ordinarily a flat surface.  Let these unfortunate men cease, then, from tormenting us and themselves about the impossibility of our retaining water in the higher regions.