1. Interior of Yerkes Observatory, Williams Bay, on Lake Geneva, Wisconsin Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
2. The 41 inch reflecting telescope Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
3. The University of Chicago Yerkes Observatory Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
4. The University of Chicago. Yerkes Observatory, Williams Bay, Wis. Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–July 25, 1908] Institution: Anna Maria College
5. Yerkes' Observatory, Lake Geneva, Wis. Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–August 8, 1914] Institution: Anna Maria College
6. The Yerkes Observatory of the University of Chicago, William Bays, Wisconsin Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
7. The University of Texas McDonald Observatory's 107-inch telescope Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
8. Comet Hyakutake photographed over the Yerkes Observatory 90-foot diameter dome in March 1996 Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: March 1996 Institution: Anna Maria College
9. 100 inch telescope dome, Mt. Wilson Observatory Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–October 2, 1936] Institution: Anna Maria College
10. 100 inch telescope, Mt. Wilson Observatory, largest in U.S.A. Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
11. 100" reflecting telescope Mt. Wilson Calif. Format: Postcards/Cards; Photographs Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
12. 150 ft. tower telescope, Mt. Wilson Observatory Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
13. The 200" telescope, Palomar Mountain, California Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
14. The 200-inch Hale telescope of the Mount Wilson and Palomar Observatories Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: (c) 1965 Institution: Anna Maria College
15. The 82-inch reflecting telescope of the W. J. McDonald Observatory of the University of Texas Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
16. The dome of Palomar Observatory's 200" telescope is shown here on the morning after a winter storm Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
17. Dome of the 100 inch Hooker Reflector, Mount Wilson Observatory, California Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–July 4, 1940] Institution: Anna Maria College
18. Giant 100 inch telescope Mt. Wilson Observatory, California Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
19. The honeycombed structure of the 200" mirror sets waiting for the thin aluminum coating that will give it its high reflectivity Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
20. Interior view of Palomar Mountain Observatory, showing details of world's largest telescope Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College