380 The American Geologist. •'"''^' ^''^^ 
two stories occupying the same embrasure, though separa- 
ted by ornamental metal work. These windows will be 
about 11^/2 feet wide, and the intervening wall space about 
7 feet wide, giving a unit for the installation of exhibits of 
18 feet 6 inches. 
The third story will be 12 feet in hight, with windows 
about 7 feet high by 5 feet 3 inches wide, furnishing 
ample light for all the requirements of the laboratories and 
storerooms. In the three main sections of the building 
there will be another low story above the third story suit- 
able for the storage of dried specimens. 
The relatively small amount appropriated for this large 
building has demanded simplicity of design and the omission 
of all extravagant decoration. The lines and proportions 
have been so well planned, however, that the structure can- 
not fail to be one of great dignity and beauty and a worthy 
addition to the public buildings in Washington. The 
granite will be laid in ashlar courses, but the entrances will 
be worked up with a certain amount of elaborateness. A 
metal dome, with skylight, will cover the rotunda, and there 
will also be skylights along the main roofs for lighting the 
large halls. 
The rotunda at the south, or main, entrance will be 
about one hundred and sixteen feet square, and lighted en- 
tirely from above. It will connect directly with the three 
great halls, which are to be similar in character and of the 
same length and width, about 209 by 116 feet, all provided 
with galleries except at the inner ends adjoining the rotun- 
da. The galleries along the sides will be 32 feet wide, leav- 
ing interspaces of 50 feet width. This central or open 
part of each main hall will 'be 148 feet long and reach to 
ceiling lights under the skylights, a distance of 60 feet, 
while the galleries and sides of the first story will receive 
their light from the large windows of the fronts and courts. 
The galleries of the second and third floors are intended to 
be entirely screened ofif from the central halls and treated 
as space that can be divided to suit the requirements. The 
space under the galleries may be treated in the same way or 
left open, as circumstances may dictate. 
The remainder of the building, consisting of the ranges 
