NATURAL HISTORY BUILDING 71 



The frames, sills, muUions, muntins and inside trim are entirely 

 of No. 20 gauge molded steel. On the exterior where the metal has 

 contact with the stone or brick work, heavy tinned sheet copper has 

 been used. The sills and other projections on which workmen are 

 likely to step in cleaning or painting are filled with concrete, and all 

 muntins are stiffened with a metal core. The glass is polished plate, 

 ^-inch thick, with the inner surface evenly ground, except in the 

 north pavilion where it has been left plain. It is held in the frames 

 by a fixed molded metal bead on the outside and a movable wood 

 bead on the inside. The metal work on the exterior has been painted 

 a light color in harmony with the white granite. 



The inside sill of the first story windows is 4 feet 4^ inches and 

 the lower glass line 4 feet 7^ inches above the floor line. The win- 

 dow height from glass line to glass line is 14 feet 5^ inches. The 

 glass area in each of the outer windows is 149 square feet, of which 

 12| square feet is movable. In the court windows of the same floor 

 the glass area is 142 square feet, of which 12 square feet is mov- 

 able. In the second story the sill line is only 4f inches, and the glass 

 line 6 inches above the floor level. The window height from glass 

 line to glass line is 13 feet 6f inches in the outer walls of the wings 

 and 13 feet 2^ inches in the ranges and all court walls. The glass 

 area is as follows : In the outside windows of the wings, 139 square 

 feet, with 7 square feet movable; in the outside windows of the 

 ranges, 136 square feet, with 6f square feet movable; and in the 

 windows of the courts, 129 square feet, with 6f feet movable. 



Windows other than those of the typical size and construction, 

 being smaller and of simple design with metal frames, occur in the 

 first and second stories in the walls of and adjacent to the stair 

 towers and those of the service stair wells on the court side, and in 

 the lateral projections of the north pavilion and the recessed walls 

 of the south portico. 



Third story windows. — There are three general sizes of window 

 openings in this story, but the windows are all of the double-hung 

 type, the sash opening at both top and bottom. The openings in 

 the fagades of the east and west wings are in pairs separated by a 

 granite mullion, and measure 4 feet wide by 6 feet 8 inches high. 

 Those over the entrances in the north pavilion are also in pairs, 

 but of slightly larger size, while the dormer openings of the 

 ranges are 5 feet wide by 7 feet high. The typical openings in the 

 court walls are 11 feet wide by 7 feet high, but are divided into 

 three sections by wood muUions, the middle section being much wider 

 than the others ; and the smaller court windows, 9 feet 5 inches wide, 

 are divided in the same manner. In all of these windows white pine 

 has been used for the sash, outside sills, staff beads, etc. ; and cabinet 

 oak, for the inside casings, trims, stools, etc. The glass is polished 



