NATURAL HISTORY BUILDING 69 



WINDOWS AND DOORS 

 WINDOWS 



There is a marked structural difference between the windows of 

 the first and second stories, containing the exhibition halls, and those 

 of the ground and third stories, the former being framed with metal 

 while the latter have frames and trims of wood. 



Ground story windows. — ^With a few exceptions, the windows in 

 the ground story are of a common pattern, casement and wood 

 construction. Those in the outer walls, 'where the openings measure 



10 feet wide by 10 feet 6 inches high, are divided vertically by 

 two mullions, each 3 feet to the side of the center of the opening. 

 The large middle section so formed is subdivided into three equal 

 parts by vertical muntins, and each of the narrow sides into three 

 lights by horizontal muntins. Except in the east w^ing, only the two 

 lower lights on each side are hinged to open, the movable sash being 

 held in angle iron frames by smaller angle irons fastened from the 

 outside. With a total window area of about 103 square feet, of 

 which about 73 feet are glazed, the aggregate area of the movable 

 sash equals about 14 square feet. A much larger area of movable 

 sash, amounting to 46 square feet, is obtained in each of the windows 

 on the south side of the east wing, where the carpenter and paint 

 shops are located adjacent to the boiler and engine room, by pro- 

 viding three hinged sashes in the middle sections of the windows in 

 addition to the typical side openings. The vertical and horizontal 

 muntins of the center division of these windows are formed of 2-inch 

 T bars. 



The windows of the court walls agree in details of construction 

 with those of the outer walls, but as the typical openings measure 



11 feet wide and 11 feet 2 inches high, there is a corresponding in- 

 crease in the size of the lights in both fixed and movable sash. The 

 hinged sash are typical except on the north side of the east wing 

 where thej'' are similar to those on the south side of the same wdng 

 Narrower court windows at the junction of walls, measuring 9 feet 

 5 inches wide, carry the same horizontal lines as the typical windows^ 

 but the vertical mullions and muntins are spaced to give movable 

 and fixed sash of similar ratio to the total window w^idth as in the 

 larger windows. Of the eight large doorways in the court walls five 

 have been transformed into windows by closing the lower part of the 

 openings which are of the same width and character as in the typical 

 windows. 



The window construction is of white pine, except the hanging stiles 

 which are of yellow pine; the inside casings, trims, sills, aprons, etc., 

 which are of cabinet oak; and the iron work of the movable sash. 

 The glass is polished plate and cleai", except in the toilet rooms where 

 it is ground on the inside face. 



