From the Preface. THE intellect of man is progressive, and cannot re- main stationary while science marks out the line of progress, and Revelation does not forbid our going forward in the work of investigation. That the earth is much older than our wisest sages were once willing to admit is a fact which science reveals to us almost daily, and which the theologian unites with us in establishing in a way not at variance with Divine revelation. The Bible and Science move together harmoniously, and where there are seeming inconsistencies there can be no controversy. Our interpretation of Scripture is either incorrect and needs modification to place it in harmony with the progress of Science, or else the scientist has failed in his deductions, and presents a dogma which has an existence only in theory and not in fact. Who believed fifty years ago that the lightnings of heaven would be used to transmit our messages from zone to zone, and from the sea to the uttermost parts of the earth? And yet Job declares, in chap, xxxviii. 35, "Canst thou send lightnings, that they may go, and say unto thee, Here we are?" The same may be said in regard to the powers of steam, when Job describes Leviathan as emitting flames from his nostrils and plowing the vasty deep, until his pathway becomes hoary with phosphorescent light. Science reveals to us the revolutions of all the planets upon their axes, and a myriad of worlds beyond our own system. Gen, i. 4, 5: "And God divided the light from the darkness. And God called the light Day, and the darkness he called Night." There is no want of harmony in all this, and yet how slow was the Christian world in adopting this new system of astronomy! The unity of the human race is comparatively a new theory, which has been strongly maintained by the translators of the English version of the Bible. However, the ancient world, and the Jews particularly, believed firmly in the diversity of the human family ; and all nations under the sun, and in every age, who have held intercourse with the dark races, have regarded them as distinct in character, and as constituting intellectually an inferior type of the genus homo.