The Exhibition building was admirably designed for its purpose. Its plan is simple, and not unpleasing, although the proportions, which its object required, were such as to prevent any attempt at grand architectural effect. The general arrangement of the interior is easily understood, even without the aid of a ground-plan. The chief entrance leads into a nave, which has on each side an aisle of less height, separated from it by a wall. The wall is broken by two openings, through which is the passage from nave to aisle, or aisle to nave. The nave and aisles end in a transept, and behind the transept are two small saloons, and a large hall or aisle crossing the building transversely and forming its western end. A gallery runs round the transept, and another crosses the nave at its eastern end. This is the general arrangement. The walls of the nave or central hall are occupied by the gallery of British portraits, and between the iron columns that support the roof are set pieces of sculpture, and the cases containing the precious collection of Ornamental Art, (works of the minor arts, as they might be called,) which has been brought together from private and public sources, and is quite unrivalled in its completeness. The southern aisle contains the main collection of pictures by ancient, foreign masters; while the opposite aisle is filled with the works of the British school. The transept, being chiefly given up to arrangements for an orchestra, contains below little but a collection of busts, but its galleries are occupied with the collection of miniatures, a most admirable and extensive historical series of engravings, a large number of photographs, and a very precious collection of original drawings by the old masters. The saloon at the north end of the transept is filled with East Indian and Chinese tapestries, furniture, and works of ornamental design; while the opposite saloon continues the collection of paintings of ancient masters, being chiefly occupied with works from the gallery of the Marquis of Hertford, which he sent to the Exhibition on condition that they should be kept together. The hall that crosses the building at the western end is filled with a collection of water-color drawings.--Such, in brief, is an outline of the distribution of the treasures contained in this great palace of Art.