It states, History should be regarded as a means for understanding the past and solving the challenges of the future. It also suggests that this celebration of the end of slavery is an important and enriching part of the history and heritage of the United States.
The plane is simply abstracting the power stored in the wave by a distant gale, and using it to counteract gravity. And if the work be continued long enough, or a multitude of planes be continually drawing on the reservoir of power, the wave must inevitably be flattened.