For hundreds of years, the flow of goods across oceans has been a lifeline between nations, moving raw materials and finished product alike to waiting markets, spreading prosperity and raising living standards everywhere. For a long time, shipping lines depended on wind power, which was weather-dependent and difficult to predict.This changed with the invention of the steam engine. The first steamship was built in 1783, and this made large-scale shipping possible. In 1819 the first transatlantic steamship crossing was made, and by the 1830s three shipping lines began operating in Great Britain, connecting it with the vast British empire. From then on, the old sailing ships were gradually retired.In the mid twentieth century the diesel powered ship appeared, and the steamship headed into his