<p>Labor Day became a national holiday in the United States in 1894, codifying what had become an American tradition of celebrating the work of labor unions with parades, picnics, and other festivities. During the 1920s and 1930s, the National Air Races were also becoming a Labor Day tradition, often held in Cleveland, Ohio. Labor Day 1932 fell on September   <a href="http://blog.nasm.si.edu/archives/thompson-trophy/">...Continue Reading</a></p> <p>The post <a rel="nofollow" href="http://blog.nasm.si.edu/archives/thompson-trophy/">Celebrating Labor Day with the Thompson Trophy</a> appeared first on <a rel="nofollow" href="http://blog.nasm.si.edu">AirSpace</a>.</p>
