_The Life and Letters of Barthold George Niebuhr. With Essays on his Character and Influence. By the Chevalier Bunsen and Professors Brandis and Lorbell. New York: Harper and Brothers. 1 vol. 12mo._ This thick volume of some six hundred pages is crammed with interesting matter. The letters of Niebuhr are among the most instructive in literature, and they range in subject over an immense extent of knowledge. The vigor of his character, and its sterling honesty, are as apparent throughout as the vast acquirements and vivid conceptions of his intellect. His comments on the poets and philosophers of Germany will be read with great interest, as he knew many of them intimately, and expresses his opinions of their defects and merits with singular sincerity and acuteness. His views of Goethe, especially, are entitled to the most thoughtful consideration. The essays on Niebuhr, at the end of the volume, are excellent. * * * * * _The Solar System. By J. Russell Hind, Foreign Secretary of the Royal Astronomical Society of London, etc. New York: Geo. P. Putnam. 1 vol. 12mo._ This is another of Putnam’s admirable publications, the first of a series on popular science, and similar in form to his “Semi-Monthly Library.” The present volume contains two hundred pages, is elegantly printed, and is sold at the low price of twenty-five cents, which is cheapening the solar system beyond all precedent. The volume is succinctly and clearly written, and contains the latest “news from the empyrean.” The only defect we have noticed is in the account given of the discovery of Neptune. The author appears to be ignorant of the important connection which Professor Pierce, of Harvard University, has established with this new planet. He did not, it is true, discover it; but he demonstrated that the planet which was discovered was not the planet which Le Verrier was seeking. * * * * * _The Diplomacy of the Revolution: an Historical Study. By William Henry Trescott. New York: D. Appleton & Co. 1 vol. 12mo._ In this small volume we have a great deal of matter, which is both interesting and new. The author has studied the subject thoroughly, and exhibits many important transactions in the Revolution in a new light. He has gained access to a number of unpublished documents, and has used them with intelligence and discrimination. * * * * * _Eleven Weeks in Europe, and What May be Seen in that Time. By James Freeman Clarke. Boston: Ticknor, Reed & Fields. 1 vol. 18mo._