I have hitherto in this part of the discussion avoided detailed reference to what may be regarded as the "prophetic day" view of the narrative of creation. This may be shortly stated as follows: In the prophetical parts of Scripture the prophet sees in vision, as in a picture or acted scene, the events that are to come to pass, and in consequence represents years or longer periods by days of vision. Now the revelation of the pre-Adamite past is in its nature akin to that of the unknown future; and Moses may have seen these wondrous events in vision--in visions of successive days--under the guise of which he presents geological time. Some things in the form of the narrative favor this view, and it certainly affords the most clearly intelligible theory as to the mode in which such a revelation may have been made to man. It is advocated by Kurtz, by the author of an excellent little work, the "Harmony of the Mosaic and Geological Records," by Hugh Miller, and more recently by Tayler Lewis. To these writers I must refer for its more full illustration, and for the grand pictorial view which it gives of the vision of the creative week. In reviewing the somewhat lengthy train of reasoning into which the term "day" has led us, it appears that from internal evidence alone it can be rendered probable that the day of creation is neither the natural nor the civil day. It also appears that the objections urged against the doctrine of day-periods are of no weight when properly scrutinized, and that it harmonizes with the progressive nature of the work, the evidence of geology, and the cosmological notions of ancient nations. I do not suppose that this position has been incontrovertibly established; but I believe that every serious difficulty has been removed from its acceptance; and with this, for the present, I remain satisfied. Every step of our subsequent progress will afford new criteria of its truth or fallacy. One further question of some interest is--What, according to the theory of long creative days and the testimony of geology, would be the length and precise cosmical nature of these days? With regard to the first part of the question, we do not know the actual value of our geological ages in time; but it is probable that each great creative aeon may have extended through millions of years. As to the nature of the days, this may have been determined by direct volitions of the Creator, or indirectly by some of those great astronomical cycles which arise from the varying eccentricity of the earth's orbit, or the diminution of the velocity of its rotation, or by its gradual cooling.