FOURTH REPORT OF THE DIRECTOR xQG/ 9 



or Washington avenue structure has resulted in an apparently very 

 advantageous division of the museum floor into two levels. Thus 

 from the main level described one rises by short flights of steps 

 5 feet to a higher platform running the entire length of the build- 

 ing on the inner side save where the space is divided by the dome 

 and the corridors into the northern wing. This subdivision affords 

 two long and somewhat narrow but not constrained chambers, one 

 covering about ii,ooo square feet, the other 5760 square feet. 

 These rooms have excellent possibilities for the display of the ex- 

 tensive collections of the relics of Iroquois and other Indian cul- 

 tures on one side, and for the botanical collections on the other. 

 The space thus available for exhibition purposes is 



Hall of Geology 30 000 square feet 



Hall of Zoology 13 886 



Hall of Archeology 11 000 '' 



Hall of Botany 5 760 



Total 60 646 



All this exhibition space is lighted entirely from above ; side light 

 is wholly excluded. It is recognized that this mode of illumination 

 will present its own problems in the effective disposition of the 

 exhibits and may call for special construction or adaptations in the 

 form of the cases in order to avoid puzzling or troublesome re- 

 flections, but it may prove to have especial advantages in flooding 

 the whole chambers with light from one direction without the inter- 

 ruption or isolation that comes from light entering separate 

 apertures, like a series of windows. 



The construction which necessitates the elevation of the inner 

 portion of the main floor also makes provision for a lower level 

 on this inner side of the museum apartments. By a descent of 7 

 feet the lower level is reached and here, on either side of the main 

 corridor to the wing, are rooms for the offices of the scientific 

 and clerical staff adequately equipped with files, storage and labora- 

 tories. This lower floor turns the corner at each angle with the 

 wing and runs beneath the offices of the Archeologist and Zoologist 

 on the level above, providing room for an Insectory on one side 

 and Artists rooms with north light on the other. This entire series 

 of offices is supplied with lateral light and the suites have their 

 own private corridors. The surface area of these offices is about 

 19,000 square feet. The total available space for all museum pur- 

 poses is practically 80,000 square feet. 



