By the late 1840s the navies of Europe included an unprecedented var­ iety of warships, as the introduction of the screw propeller added another series of steamship types to the largest fleets. By the early 1850s technological developments included the spread of screw propulsion beyond the navies of the first rank, and the death of both the line-of­ battle sailing ship and the paddle steamer as warships. The changes steam power brought to naval warfare were reflected first in the Near Eastern Crisis and the First Opium War, then in the Adriatic, Baltic, and North Sea campaigns of the revolutions of 1848-49. Finally, the Crimean War provided an opportunity for the three leading naval powers to demonstrate the state of the art in technology, tactics, and strategy, and in the process revealed the extent to which a country’s level of industrialization now shaped its naval capabilities.