LUNAR SURFACE – [PEASE, Francis Gladheim (1881-1938).] Two gold-tone photographs of the Moon taken at Mount Wilson Observatory.

The 100-inch Hooker telescope at Mount Wilson Observatory was the world's largest telescope from its completion in 1917 until 1949, and was of fundamental importance to the astronomical discoveries of the first half of the 20th century. Comprises:
1. "H 5. Northern portion of the Moon at last quarter, showing the region from Copernicus to the limb, September 15, 1919, 100-inch Hooker reflector."
2. "H 9. The moon. Region of Copernicus, photographed with the 100-inch Reflector, September 15, 1919."

8 x 10 inches each, printed captions on the versos.