There could not be a simpler incident. And yet, rightly apprehended, it reads its lesson. You have all visited the scene of it, and must all have been struck by the three salient points, if I may so speak, by which that noble gallery lays strongest hold of the memory, and most powerfully impresses the imagination,--by its gigantic plants of the first period (imperfectly as these are represented in the collection), by its strange misproportioned sea monsters and creeping things of the second, and by its huge mammals of the third. Amid many thousand various objects, and a perplexing multiplicity of detail, which it would require the patient study of years even partially to classify and know, these are the great prominent features of the gallery, that involuntarily, on the part of the visitor, force themselves on his attention. They at once pressed themselves on the attention of the intelligent though unscientific mechanics, and, I doubt not, still dwell vividly in their recollections; and I now ask you, when you again visit the national museum, and verify the fact of the great prominence of these classes of objects, to bear in mind, that the gallery in which they occur represents, both in the order and character of its contents, the course of creation. I ask you to remember that, had there been human eyes on earth during the Palæozoic, Secondary, and Tertiary periods, they would have been filled in succession by the great plants, the great reptiles, and the great mammals, just as those of the mechanics were filled by them in the museum. As the sun and moon, when they first became visible in the heavens, would have seemed to human eyes--had there been human eyes to see--not only the greatest of the celestial lights, but peculiarly the prominent objects of the epoch in which they appeared, so would these plants, reptiles, and mammals, have seemed in succession the prominent objects of the several epochs in which _they_ appeared. And, asking the geologist to say whether my replies to the mechanics were not, with all their simplicity, true to geological fact, and the theologian to say whether the statements which they embodied were not, with all their geology, true to the scriptural narrative, I ask further, whether (of course, making due allowance for the laxity of the terms botanic and zoological of a primitive language unadapted to the niceties of botanic or zoologic science) the Mosaic account of creation could be rendered more essentially true, than we actually find it, to the history of creation geologically ascertained. If, taking the Mosaic days as equivalent to lengthened periods, we hold that, in giving their brief history, the inspired writer seized on but those salient points that, like the two great lights of the day and night, would have arrested most powerfully, during these periods, a human eye, we shall find the harmony of the two records complete. In your visit to the