Felted or Woven Goods of Wool, etc; 242-249, Silk and Silk Fabrics; 250-257, Clothing, Jewelry, etc.; 258-264, Paper, Stationery, Blank Books, etc.; 265-271, Weapons, etc.; 272-279, Medicine, Surgery, etc.; 280-284, Hardware, Edge Tools, Cutlery, and Metallic Manufactures; 285-291, Fabrics of Vegetable, Animal or Mineral Materials; 292-296, Carriages, Vehicles, etc. Department III. Education and Science, comprising Classes 300-309, Educational Systems, Methods, and Libraries; 310-319, Institutions, etc.; 320-329, Scientific and Philosophical Instruments, etc.; 330-339, Architecture, Engineering, Surveying, Maps, etc.; 340-349, Physical, Social, and Moral Condition of Man.

Visitors coming in carriages alight under cover at the East entrance; those in street cars, at the South entrance. To inspect the exhibits in this building, it is estimated that the visitor will traverse about eleven miles within its walls. Excellent views of the entire interior may be obtained from balconies arranged in the four central towers.

Although the Art exhibits are classified in Department IV., the visitors will doubtless generally pass from the Main Building to the Machinery Hall, and we shall take this

Machinery Hall covers 1,402 feet in length by 360 in width, with an annex on the south, 210 by 208 feet. The ground plan shows two main avenues 90 feet wide by 1,360 feet long, with a central aisle between and an aisle on either side. Each aisle is 60 feet in width; the two avenues and three aisles making the total width of 360 feet. At the centre of the building is a transept of 90 feet in width, which at the south end is prolonged beyond the main building.. This transept, beginning at 36 feet from the main hall and extending 208 feet, is flanked on either side by aisles of 60 feet in width, and forms the annex for hydraulic machines. The superstructure consists of solid timber columns supporting roof trusses, constructed with straight wooden principals and wrought-iron ties and struts. As a general rule the columns are placed lengthwise of the building, at the uniform distance apart of 16 feet. The columns are 40 feet high to the heel block of the 90 foot span roof trusses over the avenues, and they support the heel of the 60 foot spans over the aisles, at the height of 20 feet. The outer walls are built of masonry to the height of 5 feet, and above that are composed of glazed sash placed between the columns. Portions of the sash are movable for ventilation. Louvre ventilators are introduced in continuous lengths over both the avenues and the aisles. The principal portion of the structure is one story in height, showing the main cornice upon the outside at 40 feet from the ground, the interior height to the top of the ventilators in the avenues being 70 feet, and in the aisles 40 feet. To break the long lines upon the exterior, projections have been introduced upon the four sides, and the main entrances finished with façades, rising to 78 feet in height. The east entrance will form the principal approach from street cars, from the Main Exhibition Building, and from the railroad depot.

The exhibits in this Building form Department V., and comprise Classes 500-509, Machines, Tools, etc., of Mining, Chemistry, etc.; 510-519, Machines, Tools, etc., for working in Metals, Wood, and Stone; 520-529, Machines and Imple

THE PHOTOGRAPHIC ART GALLERY.

The Centennial Cooservatory, known as Horticultural Hall, is an exceedingly band some structure, appr priate in its appointments, and in its style as well, to its purpose. It is 383 feet long and 193 wide, and is substantially built, with a view to its permanen cy, the materials used being stone, brick, ina and glass. The mais floor is occupied by the central conserva tory, 230 by 80 feet, and 55 feet high, surmounted by a lantern 170 feet long, 20 feet

wide, and 14 feet high. Running entirely

around this conserva

tory, at a height of 20 feet from the floor, is a gallery 5 feet wide. On the north and south sides of this principal room are four forcing. houses for the propa gation of young plants, each of them 100

30 feet, covered wh curved roofs of tren

and glass. Dividing the two forcing-houses in each of these sides is a vestibule 30 feet square. At the centre of the east and west ends are similar vesti bules, on either side of which are reception rooms, offices, etc. From the vestibules ornamental stairways lead to the internal galleries of the conservatory, which afford fine views of the entire interior, and which communicate with four external galleries, each 100 feet long and 10 feet wide, surmounting

ing of suitable lands on the Pennsylvania Railroad, 30 min- | the roofs of the forcing-houses. These external gallenes utes from the Exhibition Grounds, where trials of Harvesting machines will take place during June and July, and of Tilling machines during September and October.

are connected with a grand promenade, formed by the rools of the rooms on the ground floor, which has a superficial area of 1,880 square yards. From this promenade may be had