MR. RUSKIN has published a new pamphlet entitled _Pre-Raphaelitism_, in which nature, and not the critical writers, the applauded models of the day, or tradition, is declared the only true guide to excellence in art; and all modern art is held to be depraved in taste, as it were, an arid desert, in which he endeavors to set up two landmarks, John Everett, Millais, and Joseph Mallord Turner. Between these two poles stand William Hunt, who paints still life; Samuel Prout, of street architecture renown; John Lewis, the harem-scene delineator; and finally, Mulready and Landseer. The essay is keenly reviewed in the _Athenæum_, _Times_, &c., but is admitted by all to be characteristically eloquent. * * * * * The _American Art-Union_ opened its galleries on Monday evening, September 22. The collection of pictures we understand is unusually good. The occasion was one of much good feeling and enjoyment. Speeches were made by the President of the Art-Union, by Mr. Conrad, Secretary of War, by Rev. Dr. Osgood, Parke Godwin, C. A. Dana, Mr. Thompson of the Southern Literary Messenger, Judge Campbell, General Wetmore, and several other gentlemen. * * * * * POWERS'S celebrated statue of EVE, which was lost off Cape Palos in May, 1850, arrived in New-York a few days ago, in the British schooner Volo, from Carthagena, not having sustained any material injury. A letter from Mr. Powers respecting this statue was printed in the last number of _The International_. * * * * * MR. LEUTZE, after a long absence from this country, has returned, bringing with him his greatest work, _Washington Crossing the Delaware_, which will soon be exhibited at the Stuyvesant Institute. Mr. Leutze was received with great applause at the late meeting of the Art-Union. _Historical Review of the Month._ In the UNITED STATES, since our last publication, no events have occupied more attention than the great _Agricultural State Fair_ which was held recently at Rochester, and of which we shall give a particular account, illustrated with numerous engravings, in our next number; and the _Railroad Festival_ at Boston, which was held at the same time. At the latter were present the President of the United States, the Secretary of State, and other members of the Cabinet, the Governor-General of Canada, his Aids and Cabinet, the principal members of the Canadian Parliament, and the leading merchants in the Canadian cities, the Governors of New England states, the Presidents of the railways in New England, the Mayors of the cities of New England and many other influential persons interested in railways and steam navigation. Speeches were made by the President of the United States, by Lord Elgin, Daniel Webster, Edward Everett, and many others, and the occasion was altogether one of the most brilliant and satisfactory of its kind ever known in this country.