500 



REPORT OF NATIONAL MUSEUM, 1903. 



ut a cost of $800,000 and was opened in 1897. In spite of its youth 

 it has ah"eady obtained a world-wide reputation under the direction of 

 Prof. G. E. Hale. As I have not visited it I can only give a notice 

 compiled from various sources. As early as 1892 Charles T. Yerkes 

 conferred with Messrs. Harper and Hale concerning- its foundation, 

 and the latter in 1893 had the plans drawn up. The site was selected 

 with care so as to be as free as possible from disturbances. It is 220 

 feet above the lake and 1,300 feet above sea level. About 50 acres of 

 woodland are included in the site. The building, likewise designed by 

 Henry Ives Cobb, is T-shaped, its principal axis (361 feet) lying east 



Fig. 76.— University of Chicago. Yerkes Astronomical Observatory. 



and west. The dome for the telescope, which is 75 feet long with an 

 objective of 33 inches, is at the western end and is 98 feet in diameter. 

 This great telescope" is moved by an electrical apparatus, and the floor 

 of the observing room, 82 feet in diameter, can be elevated and is 

 movable through a range of 26 feet by means of electrical motors 

 (tig. 77). A spectrograph, a photoheliograph, as well as a stellar and 

 a solar spectrograph are attached to it. In the eastern wing, which 

 runs north and south, is the heliostat room, 108 feet long and 13 feet 



« It was exhibited in Chicago in 1893, and was until up to within a short time the 

 largest in existence. One was made for the Paris exposition of 1900 having an 

 objective 1.25 meters in diameter, and recently an American has offered one to the 

 Pope that is still larger. 



