116 TJlSriTED STATES NATIONAL MUSEUM 



piercings for the light wells, the enclosing walls of which contain 

 the structural columns and present a flush surface broken only by 

 the several balcony openings overlooking the central halls. Each of 

 the wings in this story contains, therefore, two elongate halls, one on 

 each side of the light well, communicating with the first gallery in 

 the pavilion by means of a large doorway, and opening into the space 

 at the outer end of the wing, which, in the east and west wings, takes 

 the shape of a shorter but broader hall. 



In the east and west wings the side halls have a length of about 

 169 feet 6 inches and an average width of about 31 feet 3 inches, 

 being between 3 and 4 inches wider on the south side than on the 

 court side. The end halls are 116 feet 2 inches long, which is the 

 width of the wing, and 46 feet 6 inches wide. In the north wing 

 the side halls measure 170 feet 5 inches by 31 feet 1 inch. The outer 

 end of the wing is subdivided as in the story below, the north pavil- 

 ion containing the staircase on one side and the elevator shaft and 

 small room on the other, while the intervening space adjoining the 

 large windows, and measuring 70 feet 1 inch long by 15 feet 8 inches 

 wide, is enclosed in front by a screen wall 21^ inches thick. This 

 wall, separated from the end of the light well enclosure by a pas- 

 sageway about 17 feet 3 inches wide, has five openings 13 feet 10 

 inches high, the middle one being 11 feet 2^ inches wide, those 

 next following on each side, 9 feet 8 inches, and the lateral ones, 5 

 feet 7^ inches. It is, moreover, joined at right angles by a con- 

 tinuation of each of the side walls of the light wells, with piercings 

 15 feet 3 inches high and 13 feet 7^ inches wide. 



The amount of exhibition space afforded by the second story in 

 the wings and ranges is 79,028 square feet, of which 30,467 feet are 

 used by the department of anthropology, 32,634 feet by the depart- 

 ment of biology, and 15,927 by the department of geology. The 

 anthropological collections, which occupy the north wing and east 

 range, are illustrative of American and Old World archeology; the 

 biological collections, installed in the west wing and west range, 

 include the reptiles, fishes, invertebrates and the osteological and 

 special exhibits ; and the geological collections, contained in the east 

 wing, comprise the minerals and gems and the building and other 

 useful stones. 



THIRD STORY 



The floor layout in the third story corresponds with that in the 

 second story and the aggregate amount of space is practically the 

 same, notwithstanding certain variations in the floor measurements. 

 For instance, while the walls of the light wells are 2 feet thick in 

 the second story, their thickness in the third story is only about 5 

 inches, and the width of the spaces at the sides and ends of the wells 



