The reader must not think it amiss, in this distribution of the Mosaic Days, that four out of six are crowded together into one Geological Age, while each of the other two has an entire Age assigned to itself. If the Days of Creation were indefinite periods, there is no incongruity in supposing that one may have corresponded to a longer, another to a shorter interval in the history of our planet. But, in truth, our scheme of distribution does not of necessity imply that the Mosaic Days were periods of unequal length. Geologists do not pretend that there is even a remote approximation to equality between the several divisions of Geological time. The three great Epochs are distinguished from each other by reason of the very marked difference in the character of their Fossil Remains. And the multiplication of Periods in each Epoch seems to depend rather upon the degree of completeness with which the strata of that Age have been examined, than upon any conjecture as to the probable length of its duration. Thus, for example, Sir Charles Lyell thinks that, as far as the present condition of Science affords the means of forming an opinion, almost any one of the Periods in the Palæozoic Age was as long as all the Periods of the Tertiary Age taken together.[175] But there is another and a more serious objection against our hypothesis. It has been observed more than once that the periods of Geology are out of harmony with the Days of Genesis, even as regards the history of Organic life. According to the Scripture narrative no Organic life appeared upon the Earth previous to the Third Day. Now the Third Day of Scripture corresponds, in our scheme, with the Carboniferous Period of Geology. And yet there is abundant evidence in the Fossil Remains of the Devonian, the Silurian, and the Cambrian Formations, that Organic life--both plants and animals--prevailed upon the Earth for many ages before the Carboniferous Period began. Nay, it is now commonly held, since the discovery of the famous _Eozoon Canadense_, the oldest known Fossil, that life already existed during the deposition of the Laurentian Rocks, the earliest of all the Stratified Formations. Furthermore, in the Mosaic account, Fish are represented as having been created only on the Fifth Day, which we have fitted in with the Secondary Age of Geology: whereas in the Geological Record we find Fish as early as the Silurian Period, which is far back in the Primary Age. These considerations, and divers others of a like nature, have been regarded by some eminent writers as altogether fatal to the hypothesis for which we are contending.