One of the most striking lectures in Mr. Mitchell's volume is that on the discoveries of the primitive ages, in which he represents the processes of the primitive observer, with his unarmed eye, in unfolding some of the laws of the heavens; and he indicates with great beauty what would be his point of departure, and what would be the limit of his discoveries. This lecture is a fine prose poem. There is a passage in the introductory lecture which grandly represents the continual watch which man keeps on the heavens, and the slow, silent and sure acquisitions of new truths, from age to age. "The sentinel on the watchtower is relieved from duty, but another takes his place, and the vigil is unbroken. No--the astronomer never dies. He commences his investigations on the hill-tops of Eden--he studies the stars through the long centuries of antedeluvian life. The deluge sweeps from the earth its inhabitants, their cities and their mountains--but when the storm is hushed, and the heavens shine forth in beauty, from the summit of Mount Arrarat the astronomer resumes his endless vigils. In Babylon he keeps his watch, and among the Egyptian priests he inspires a thirst for the sacred mysteries of the stars. The plains of Shinar--the temples of India--the pyramids of Egypt, are equally his watching places. When science fled to Greece, his home was in the schools of her philosophers: and when darkness covered the earth for a thousand years, he pursues his never-ending task from amidst the burning deserts of Arabia. When science dawned on Europe, the astronomer was there--toiling with Copernicus--watching with Tycho--suffering with Gallileo--triumphing with Kepler." We trust that this volume will have an extensive circulation. It will not only convey a great deal of knowledge to the general reader, but will also inspire a love for the science of which it treats. _Harold, the last of the Saxon Kings. By Sir Edward Bulwer Lytton, Bart. New York: Harper & Brothers._