Workers conduct seismic explosions in search of oil and gas deposits on private islands in Bob Marshall Wilderness Area, Montana. (Corbis Corporation)

From the earliest times, ships and boats were propelled by human power and wind power. In the nineteenth century very large and efficient sailing ships (many 70 to 100 m long) were transporting passengers and cargo to ports all over the world. In the Western world most of the cargoes were carried by sailing ships until the 1890s. By the middle of the nineteenth century, with the development of reliable steam engines, the designers of ships began to use coal-burning steam power plants to propel ships, using paddle wheels and then propellers. Other power plants were developed in the late nineteenth century and during the twentieth century, including steam turbines, spark-ignition engines, diesel engines, gas turbines, and nuclear power plants. These ship power plants were developed from their...