41 
HALLS 60 AND 61. 
GEOGRAPHIC GEOLOGY. 
The purpose of the exhibit of this department is to illustrate 
in a vivid and realistic way the surface configuration of the earth. 
The chief feature of the exhibit is a series of relief maps which 
reproduce on as natural and representative scales as practicable 
the topography and structure oF selected portions of the earth’s 
surface. A part of the series show only topography and culture, 
while another part show geological structure as well as topography. 
To some extent, the topography is shown on one map and the 
geological structure on another, so that both elements are repre- 
sented with the greatest distinctness. The portions of the surface 
selected to be represented are usually such as to portray some 
typical form of surface sculpturing or of volcanic accumulation. 
Some, however, represent natural or political divisions. 
In addition to the relief maps, there are models showing geo- 
logical structure or illustrating methods* of development. Some of 
these are dissected so as to show the more intimate structure of 
the formations. The exhibit also contains a collection of globes, 
wall maps, portfolios, and other geographic material. The fol- 
lowing is a list of the principal features: 
No. 1. — Relief Map of the Uinta and Wasatch Mountains, 
colored to show geOxOgical formation. Horizontal scale, i in., 
equals 4 miles, or 1.253440. Vertical scale, 1.126720. 
No. 2. — Relief map of theYellowstone National Park, showing 
Canons of the Yellowstone and Madison Rivers, etc. Horizontal 
and vertical scale, i in., equals i mile, or 1.63360. 
No. 3. — Relief map of the region of extinct volcanoes in Au- 
vergne, central France, geological and topographical. Henri 
Le Coq and G. P. Scrope. 
No. 4. — Relief map of the Ice Spring craters, a group of 
extinct volcanoes near Filmore, Utah, illustrating the successive 
formation and partial obliteration of craters and lava fields. Hor- 
izontal and vertical scales, 1.1200, i in. equals loo feet. 
No. 5. — Relief map of Massachusetts, from maps of the 
United States Geological Survey and the Topographic Survey of 
