(AP Photo)
Secretary Ray Lyman Wilbur drives the last spike into the railroad leading from Las Vegas to the site of the Hoover Dam, better known as the Boulder Dam, on Sept. 19, 1930. The spike, made of silver, signaled actual beginning of construction on the $165,000,000 project. Pictured are, from left, Congressman William Eaton of Colorado; Sen. Key Pittman of Nevada; Secretary Wilbur, and left, Sen. Samuel Shortridge.