MACHINERY HALL, of which PEABODY & STEARNS, of Boston, are the architects, has been pronounced by many architects second only to the ADMINISTRATION BUILDING in the magnificence of its appearance. This building measures 850 x 500 feet, and with the MACHINERY ANNEX and POWER HOUSE, cost about $1,000,000. It is located at the extreme south end of the Park, midway between the shore of Lake Michigan and the west line of the Park. It is just south of the ADMINISTRATION BUILDING, and west and across a Lagoon from the AGRICULTURAL BUILDING, The building is spanned by three arched trusses, and the interior presents the appearance of three railroad train-houses side by side, surrounded on all of the four sides by a gallery 50 feet wide. The trusses are built separately, so that they can be taken down and sold for use as railroad train-houses. In each of these long naves there is an elevated traveling crane running from end to end of the building, for the purpose of moving machinery. These platforms are built so that visitors may view from them the exhibits beneath. The power for this building is supplied from a power-house adjoining the south side of the building. The two exterior sides adjoining the Grand Court are rich and palatial in appearance.

All of the buildings on this great plaza are designed with a view to making a grand background for display, and, in order to conform to the general richness of the court and add to the striking appearance, the two facades of the MACHINERY HALL on the court are rich with colonnades and other features, The design follows classical models throughout, the detail being followed from the renaissance of Seville and other Spanish towns, as being appropriate to a Columbian celebration, An arcade on the first story admits passage around the buildings under cover, and as in all the other buildings, the front is formed of "staff" colored to an attractive tone; the ceilings are enriched with strong color. A colonnade with a cafe at either end forms the length between MACHINERY and AGRICULTURAL HALLS, and in the center of this colonnade is an archway leading to the Cattle Exhibit. From this portico there extends a view nearly a mile in length down the Lagoon, and an obelisk and fountain in the Lagoon form the southern point of this vista,.

The MACHINERY ANNEX adjoins MACHINERY HALL on the west, and is an annex in fact, and not a detached structure as at first planned, with entrance by subways under the railway tracks. The ANNEX covers between four and five acres and increases the length of the Machinery building to nearly 1,400 feet, thus rendering it the second largest of all the Exposition structures, the great manufactures building alone exceeding it in size.