the light bulb, the trolley, and the moving picture. Twain the states that America was flying into the 20th century on the wings of invention and the winds of change, and that since we were facing these new changes, we needed people like Teddy Roosevelt and John Muir to lead us.
===Early 20th Centuryand WWI=== The next scene in the American Adventure shows Teddy Roosevelt and John Muir standing on a rock, debating the need for national parks. Muir is eventually able to impress upon the president that Roosevelt needs to stop the massive destruction of America's national parks. After Roosevelt says he agrees that they need to protect the countries resources, Muir says: {{Quotation| Then start it here and now. <br> Make this valley a part of Yosemite National Park. |John Muir.}} As the rock that Roosevelt and Muir are standing on, lowers into the stage, Mark Twain comments that that "Ready or not, we were soon thrust into the hectic role of a world leader and into the war to end all war". Following this proclamation, footage of World War I is shown, including a picture of Sopwith Camel, with the caption, "Another enemy airplane falls to America's gallant ace Captain Eddie Rickenbacker.” After this, the scene changes to a parade being held in honor of Charles Lindbergh. A news report is then heard, during which the newscaster tells guests that Lindbergh successfully made a solo flight across the Atlantic Ocean, aboard his plane, the Spirit of St. Louis. As the newscast finishes, guests hear a second newsman who tells them, that on October 29, 1929 the stock market has crashed.