the execution of his trust in all respects amply vindicated the high opinion entertained of Dr. Cogswell's fitness for his position. The plans for the edifice submitted by Mr. Saeltzer having been adopted, the work was commenced and has been vigorously prosecuted until the present time, when the front and nearly all the exterior are completed. The Library is of brown stone, and in the Byzantine style, or rather in that of the palaces of Florence, and is one hundred and twenty feet long, sixty-five feet wide, and sixty-seven feet high. Scarcely a particle of wood enters into its composition. No building in the United States, of this character, is formed to so large an extent of iron. Its uses, too, are altogether novel, at least in this country, and ingenious. For instance, the truss beams, supporting the principal weight of the roof, are constructed of cast iron pipes, in a parabolic form, on the same plan as the iron bridges in France and other parts of Europe, with a view to secure lightness and strength. The Library Hall, which occupies the second floor, is one hundred feet high, and sixty wide, in the clear. The ascent from the front is by a single line of thirty-eight Italian marble steps, decorated on either side, at the entrance, by a stone sphinx. Upon nearing the summit of these steps, the visitor finds himself near the centre of this immense alcove, surrounded by fourteen brick piers, plastered and finished in imitation of marble, and supporting iron galleries, midway between the floor and the ceiling. The side walls form one continuous shelving, of a capacity sufficient for 100,000 volumes. This is reached by means of the main gallery, in connection with which are four iron spiral stairways and an intervening gallery, of a lighter and smaller description, connected by its eight staircases with the main gallery. The whole are very ingeniously arranged and appropriately ornamented, in a style corresponding with the general architecture of the building. At an elevation of fifty-one feet above the floor of the main hall, is the principal skylight, fifty-four feet long and fourteen broad, formed of thick glass set in iron. Besides this there are circular side skylights of much smaller dimensions. All needful light is furnished, by these and by the windows in the front and rear walls. Free ventilation is also secured by iron fretwork, in suitable portions of the ceiling. In the extreme rear are the two rooms for the librarian, to which access is had by means of the main galleries.