1. 1911, Niagara Falls frozen in cold weather, people can be seen in this photo taking the opportunity to walk all the way to the falls.
2. A funny photo of the Beatles and boxing champion Muhammad Ali.
3. Arnold Schwarzenegger celebrated the day he received his U.S. citizenship.
4. Microsoft Windows 95 launch day, the joy for the first person who bought this software is no less than the one who have bought the latest iPhone nowadays.
5. A cigarette vending machine appeared on the streets of England in 1931, where you could buy a lit cigarette by putting in a penny.
6. The Manhattan Bridge under construction, taken in 1908.
7. Steven Spielberg was inspecting the miniature landscape model used in filming when directed "Raiders of the Lost Ark", taken in 1980.
8. John F. Kennedy and his daughter Caroline having afternoon tea together.
9. Times Square in New York City in 1943.
10. Union Station in Washington, D.C., taken in 1905.
11. Mount Rushmore, still under construction, with the presidents' faces carved out in profile.
12. In 1949, the United States developed the recumbent pilot's seat, which was designed to reduce pilot fatigue and the effects of gravity.