1. Observatory, Ohio State University, Columbus, Ohio 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. Ann Arbor, Mich. University of Michigan, the observatory Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
4. Climax Station of the High Altitude Observatory, University of Colorado Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
5. A fireworks display is staged near the 107-inch dome at the University of Texas McDonald Observatory Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1969–1996] Institution: Anna Maria College
6. 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
7. Kirkwood Observatory, Indiana University, Bloomington, Indiana Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
8. McDonald Observatory Ft. Davis Tex. Format: Postcards/Cards; Photographs Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
9. McDonald Observatory on Mt. Locke Format: Postcards/Cards; Photographs Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–June 21, 1933] Institution: Anna Maria College
10. McDonald Observatory on scenic drive - Davis Mts Format: Postcards/Cards; Photographs Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–April 18, 1940] Institution: Anna Maria College
11. Morningside College- Sioux City, Iowa Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
12. Observatory and lake view. St. John's University, Collegeville, Minn. Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: (c) 1907 Institution: Anna Maria College
13. The observatory at Bucknell University, Lewisberg, Pa., offers fine facilities for study and research in astronomy Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
14. Observatory, College of Wooster, Wooster, Ohio Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
15. Observatory Hall, University of Wisconsin, Madison, Wis. Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
16. Observatory, Mt. Holyoke College, South Hadley, Mass. Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–January 14, 1910] Institution: Anna Maria College
17. Observatory, Ohio Wesleyan University, Delaware, Ohio Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–July 1912] Institution: Anna Maria College
18. Observatory, Princeton University, Princeton, N.J. Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–November 19, 1906] Institution: Anna Maria College
19. The observatory, Smith College, Northampton, Mass. Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–1996] Institution: Anna Maria College
20. The observatory, University of Minnesota Format: Postcards/Cards Collection: Travel Postcards of Charles Blumsack Date: [ca. 1906–June 1907] Institution: Anna Maria College
