sentences:  Much of the energy from the ship's propeller only results in waves and turbulence between the two layers of water, leaving a ship capable of traveling at perhaps as little as 20% of its normal speed.The phenomenon was first described by Fridtjof Nansen, the Norwegian Arctic explorer.Nansen wrote the following from his ship "Fram" in August 1893 in the Nordenskiöld Archipelago near the Taymyr Peninsula