The major innovations were again in hull material and propulsion. The transition from iron to steel hulls further liberated naval engineers. Lighter, stronger, and less brittle, steel allowed them more play in hull size and proportions. Despite extensive use of ironclads by the United States during the Civil War, its navy essentially skipped the iron stage in seagoing warships, moving from _Hartford_-type wooden steamers to the steel ABCD ships of 1883. While the Charlestown yard launched no steel warships until the 1930s, it did construct the tug _Pentucket_ (1903) and training bark _Cumberland_ (1904), both steel-hulled. As steam engines grew more efficient in the 1880s and ’90s, sailing rigs were made smaller and vestigial masts served mainly as radio antennae and platforms for directing big guns. But a revolution in steam technology sent reciprocating engines the way of masts on most large naval vessels. Steam turbines, which were much more efficient at sustained high speeds, were developed in the 1880s in Europe and used in 1905 on _Dreadnought_. In America they became truly practical during the World War I period. Along with the introduction of turbines came an innovation in the fuel that powered them. During the 1890s oil was introduced, used in combination with coal. By 1910 the United States had built its first all oil-burning warship. Besides providing greater power more quickly, oil needed less storage space and fewer engine room hands than coal. These advances and refinements completed the evolution of the U.S. Navy warship from wooden-hulled sailing vessel to powered steel ship. But perfecting the new technology was not the only challenge associated with the transition. The demands of modern naval design provoked growing controversy over how work should be performed at naval shipyards and how those yards should be organized. Charlestown Navy Yard played a central role in the debate. Since 1868 the nation’s naval shipyards had each been organized into departments corresponding to those at the Navy Department level. Each department head, though nominally under the yard commandant, really worked for his boss in Washington. So each department became in effect a separate plant protecting its own interests and budget. When a yard built relatively simple wooden-hulled ships powered by steam engines, the tasks of the Construction and Steam Engineering departments differed enough that there was little overlap. The old organization was not then a problem. But as warships became complex, integrated machines the system broke down, providing little coordination between departments and a great deal of duplication. By 1910 it was grossly wasteful and inefficient, a public scandal.