Alexander Graham Bell first displayed his electric telephone in 1876 at the Centennial Exhibition in Philadelphia, Pennsylvania.
- What was the first cartoon shown in U.S. movie theaters with a regular feature?
- What was the first movie shown in the White House?
- When was the first public opinion poll taken?
- When did Central Park in New York first open to the public?
- Was Gerald R. Ford the first incumbent president to agree to public debates with a challenger?