But I have said that with the Hebrews the "firmament" derives its name from a verb in their language signifying "to extend." It is to this signification of the Hebrew verb that David beautifully alludes, in his similitude of military hide-coverings and tents which he uses in Ps. 104:2, when he says of God "Who stretcheth out the heavens like a curtain." For as the rolled-up hide-covering of the military tent is unrolled and then stretched out as a canopy to the stakes which are fixed in the earth, so Thou, O God, says David, unrolledst as it were and stretchedst out the first formed, but as yet unformed, rude heaven, into the present glorious "firmament," where Thou sittest invisibly as on a sphere over the whole creation, in the midst of all things and yet out of and above all things. It is a circumstance naturally exciting our particular wonder that Moses evidently makes three distinct parts or divisions of this portion of the creation. He describes "a firmament in the midst of the waters," which "divides the waters from the waters." For myself I am inclined to think that the firmament here mentioned is the highest body of all; and that the waters, not those "above" the firmament, but those which hang and fly about "under" the firmament, are the clouds, which we behold with our natural eyes; so that by the waters which are "divided from the waters," we may understand the clouds which are divided from our waters which are in the earth. Moses however speaks in the plainest possible terms, both of waters "above" and of waters "under" the firmament. Wherefore I here hold my own mind and judgment in captivity and bow to the Word, although I cannot comprehend it. But a question here arises, what those waters are and how those bodies of water which are "above" the firmament are distinguished from those which are "under" the firmament. The division and distinction here made by philosophers is well known. They make the elements to be four; and they distinguish and place them according to their qualities. They assign the lowest place to the earth; a second place to the water; a third to the air; and the last and highest place to the fire. Other philosophers add to these four elements ether as a fifth essence. After this division and number of the elements, there are numerated seven spheres or orbs of the planets, and an eighth sphere of the fixed stars. And on these subjects it is agreed among all philosophers that there are four spheres of generating and corruptible principles; and also eight others of non-generating and incorruptible principles.