These two lectures formed parts of a course delivered during the winter of 1862-63, by some of the professors of the St. Louis University. They are admirable compositions, redolent of good sense, learning, and ripe thought, and deeply interesting. The style has a true oratorical ring. In the first lecture Father Heylen, after adverting to the fact that every age since the days of Adam has been marked by some special characteristic, examines the claim set forth by our own century to be emphatically the age of progress. In part he admits and in part he denies it. In material progress, and in the natural sciences, especially as applied to the purposes of industry and commerce, it stands at the head of ages. But moral progress is not one of its characteristics. "Here I feel," says he, "that I am entering upon a difficult question. Has there been, in the last fifty years, any marked increase of crime? Is our age, all things considered, really worse than preceding ages? This question I shall not undertake to decide; but there are some forms of crime which appear to me decidedly peculiar to our age." A brief review of these sins of the day leads naturally to the subject of the second lecture. Father Heylen sees our greatest danger in that practical materialism which places material interests and materialistic passions above the interests of the soul and the claims of virtue. He considers successively its extent, its effects, and the means to avert it--the last being, of course, the ennobling and spiritualizing influence of Catholicism. We advise those who wish to see how a scholar and an orator can throw a fresh charm into a stale subject, to read Father Heylen's review of the startling discoveries of modern science in the first lecture, and his brilliant description in the second of the ruins with which materialism has spread the pages of history and the new life which Catholicism has infused into effete civilizations. Prefixed to the little volume before us is a short biographical sketch of Father Heylen, who died in 1863. UNDINE, OR THE WATER-SPIRIT. Also SINTRAM AND HIS COMPANIONS. From the German of Friedrich de la Motte Fouqué. I vol. 12mo., pp. 238. New York: James Miller. THIODOLF, THE ICELANDER. A Romance. From the German of the Baron de la Motte Fouqué. 12mo., pp. 308. New York: James Miller.