According to the theory of Mosaic geology ultimately adopted by Hugh Miller, the 'beginning' spoken of in the first verse of the Bible corresponds to that period when the planet, wrapt in primeval fires, was about to enter upon the series of changes which is inscribed in the geologic record. The chaos, dark and formless, which preceded the dawn of organic existence upon earth, was no temporary inundation, no miraculous catastrophe, but an actual state of things of which the evidence still exists in the rocks. Strictly speaking, indeed, the term 'chaos' has no scientific meaning. Science is acquainted with no period in time, no locality in space, where there has been a general suspension of law; and it may be worthy of remark that, although Scripture speaks of the original state of things as without form and void, there is no hint that it was beyond control of Divine and natural ordinance. Relatively to man, however, and to those changes in the structure and organisms of the planet which the geologist chronicles, the fiery vesture, in which advocates of the Age theory of reconciliation between Genesis and geology allege the earth to have been at one time enveloped, constitutes an interruption to all research, a commencement of all that can be called scientific discovery. If it could be shown that the first chapter of Genesis contains an intelligible and accurate account of the changes which have taken place in the crust of the earth from the time when form first rose out of formlessness, and light sprang from darkness, to the time when man began to build his cities and till his fields, no candid judge would refuse to admit that the problem presented by the chapter had been satisfactorily solved, and that the chapter itself formed a sublimely appropriate vestibule to the temple of Revelation.
Let us state Miller's conception of the meaning and scientific purport of the first chapter of Genesis in his own words:--
'What may be termed,' we quote from the _Testimony of the Rocks_, 'the three geologic days--the third, fifth, and sixth--may be held to have extended over those Carboniferous periods during which the great plants were created--over those Oolitic and Cretaceous periods during which the great sea-monsters and birds were created--and over those Tertiary periods during which the great terrestrial mammals were created. For the intervening, or fourth day, we have that wide space represented by the Permian and Triassic periods, which, less conspicuous in their floras than the periods that went immediately before, and less conspicuous in their faunas than the periods that came immediately after, were marked by the decline and ultimate extinction of the Palæozoic forms, and the first partially developed beginnings of the secondary ones. And for the first and second days there remains the great Azoic period, during which the immensely developed gneisses, mica-schists, and primary clay-slates were deposited, and the two extended periods represented by the Silurian and Old Red Sandstone system. These, taken together, exhaust the geological scale, and may be named in their order as, first, the Azoic day or period; second, the Silurian, or Old Red Sandstone day, or period; third, the Carboniferous day, or period; fourth, the Permian or Triassic day, or period; and sixth, the Tertiary day, or period.'