What space of time was in reality occupied by the "day" of Genesis, is not at present of any importance for us to consider. By what furnaces of fire the adamant was melted, and by what wheels of earthquake it was torn, and by what teeth of glacier and weight of sea-waves it was engraven and finished into its perfect form, we may, perhaps, hereafter endeavour to conjecture; but here, as in few words the work is summed by the historian, so in few broad thoughts it should be comprehended by us; and, as we read the mighty sentence, "Let the dry land appear," we should try to follow the finger of God as it engraved upon the stone tables of the earth the letters and the law of its everlasting form, as gulf by gulf the channels of the deep were ploughed; and cape by cape the lines were traced with Divine foreknowledge of the shores that were to limit the nations; and chain by chain the mountain walls were lengthened forth, and their foundations fastened for ever; and the compass was set upon the face of the depth, and the fields and the highest part of the dust of the world were made; and the right hand of Christ first strewed the snow on Lebanon, and smoothed the slopes of Calvary. It is not, I repeat, always needful, in many respects it is not possible, to conjecture the manner or the time in which this work was done; but it is deeply necessary for all men to consider the magnificence of the accomplished purpose, and the depth of the wisdom and love which are manifested in the ordinances of the hills. For observe, in order to bring the world into the form which it now bears, it was not mere _sculpture_ that was needed; the mountains could not stand for a day unless they were formed of materials altogether different from those which constitute the lower hills, and the surfaces of the valleys. A harder substance had to be prepared for every mountain chain, yet not so hard but that it might be capable of crumbling down into earth fit to nourish the Alpine forest, and the Alpine flower; not so hard but that in the midst of the utmost majesty of its enthroned strength there should be seen on it the seal of death, and the writing of the same sentence that had gone forth against the human frame, "Dust thou art, and unto dust shalt thou return." And with this perishable substance the most majestic forms were to be framed that were consistent with the safety of man; and the peak was to be lifted and the cliff rent, as high and as steeply as was possible, in order yet to permit the shepherd to feed his flocks upon the slopes, and the cottage to nestle beneath their shadow. And observe, two distinct ends were to be accomplished in doing this. It was, indeed, absolutely necessary that such eminences should be created, in order to fit the earth in any wise for human habitation; for without mountains the air could not be purified, nor the flowing of the rivers sustained, and the earth must have become for the most part plain, or stagnant marsh.