Question: Which 20th century battleship featured artillery with a specially reinforced barrel and steam turbine propulsion?
Context: The Ljungström turbine is a steam turbine innovated in the early 20th century by the Swedish brothers Birger (1872-1948) and  Fredrik Ljungström (1875-1964).  It is also known as the STAL turbine, from the company name STAL (Swedish: "Svenska Turbinfabriks Aktiebolaget Ljungström" ). The dreadnought was the predominant type of battleship in the early 20th century.  The first of its kind, the Royal Navy's "Dreadnought" , made such a strong impression on people's minds when launched in 1906 that similar battleships built subsequently were referred to generically as "dreadnoughts", and earlier battleships became known as "pre-dreadnoughts".  "Dreadnought"' s design had two revolutionary features: an "all-big-gun" armament scheme, with more heavy-calibre guns than previous ships, and steam turbine propulsion.  As dreadnoughts became a symbol of national power, the arrival of these new warships was a crucial catalyst in the intensifying naval arms race between the United Kingdom and Germany.  With the launch of a single ship, "Dreadnought", the scales of naval power were reset overnight.  As a result, dreadnought races sprang up around the world, including in South America, during the lead up to World War I.  Successive designs increased rapidly in size and made use of improvements in armament, armour, and propulsion throughout the dreadnought era.  Within five years, new battleships had outclassed "Dreadnought".  These more powerful vessels were known as "super-dreadnoughts".  Most of the original dreadnoughts were scrapped after the end of World War I under the terms of the Washington Naval Treaty, but many of the newer super-dreadnoughts continued to be used throughout World War II.  The only surviving dreadnought is USS "Texas" , located near the San Jacinto Battleground State Historic Site. The "Florida"-class battleships of the United States Navy comprised two ships: "Florida" and "Utah" .  Launched in 1910 and 1909 respectively and commissioned in 1911, they were slightly larger than the preceding "Delaware" class design but were otherwise very similar.  This was the first US battleship class in which all ships received steam turbine engines.  In the previous "Delaware"-class, "North Dakota" received steam turbine propulsion as an experiment while "Delaware" retained triple-expansion engines. Aki (安芸 ) was a "Satsuma"-class semi-dreadnought battleship built for the Imperial Japanese Navy (IJN) during the first decade of the 20th century.  She was the second battleship built domestically in Japan and the first to use steam turbines for propulsion.  The ship was named for Aki Province, now a part of Hiroshima Prefecture.  The ship saw no combat during World War I.  "Aki" was disarmed in 1922 and sunk as a target in 1924 in accordance with the terms of the Washington Naval Treaty of 1922. The armored cruiser was a type of warship of the late 19th and early 20th centuries.  It was designed like other types of cruisers to operate as a long-range, independent warship, capable of defeating any ship apart from a battleship and fast enough to outrun any battleship it encountered.  Varying in size, it was distinguished from other types of cruiser by its belt armor—thick iron (or later steel) plating on much of the hull to protect the ship from shellfire much like that on battleships.  The first armored cruiser, the Imperial Russian Navy's "General-Admiral" , was launched in 1873 and combined sail and steam propulsion.  By the 1890s cruisers had abandoned sail and took on a modern appearance. The "Boadicea"-class cruiser was a pair of scout cruisers built for the Royal Navy in the first decade of the 20th century.  They were the first class of this type to be fitted with steam turbine machinery.  Upon completion in 1909–10, the sister ships served as flotilla leaders for destroyer flotillas of the First Fleet until 1913 when they were assigned to battleship squadrons.  When the First World War began in August 1914, they remained with their squadrons as the First Fleet was incorporated into the Grand Fleet, although they changed squadrons over the course of the war.  Both ships were present during the Battle of Jutland in mid-1916, but neither fired a shot.  They were converted into minelayers the following year and both ships laid minefields in early 1918 in addition to other missions.  The sisters were reduced to reserve in 1919 and sold for scrap in 1921 and 1926. The first recorded rudimentary steam engine was the aeolipile described by Heron of Alexandria in 1st-century Roman Egypt.  Several steam-powered devices were later experimented with or proposed, such as Taqi al-Din's steam jack, a steam turbine in 16th-century Ottoman Egypt, and Thomas Savery's steam pump in 17th-century England.  In 1712, Thomas Newcomen's atmospheric engine became the first commercially successful engine using the principle of the piston and cylinder, which was the fundamental type steam engine used until the early 20th century.  The steam engine was used to pump water out of coal mines The Mark 10 torpedo was a torpedo put into use by the United States in 1915.  It was derived from the Mark 9 aircraft torpedo converted to submarine use.  It was used as the primary torpedo in the R- and S-class submarines.  It used alcohol-water steam turbine propulsion.  It was succeeded by the problematic Mark 14 torpedo, but remained in service in S-boats & fleet submarines through the Pacific War.  The Mark 10 featured the largest warhead (497 lb of TNT) of any U.S. torpedo developed at that time.  Stockpiles of Mark 10 Mod 3 torpedoes were used extensively during the first part of World War II due to short supply of the newer and longer (246 in Mark 14s, with some fleet submarines carrying a mixture of both types on patrol. Steam-powered vessels include steamboats and steamships.  Smaller steamboats were developed first.  They were replaced by larger steamships which were often ocean-going.  Steamships required a change in propulsion technology from sail to paddlewheel to screw to steam turbines.  The latter innovation changed the design of vessels to one that could move faster through the water.  Engine propulsion changed to Steam turbine in the early 20th century.  In the latter part of the 20th century, these, in turn, were replaced by gas turbines. A built-up gun is artillery with a specially reinforced barrel.  An inner tube of metal stretches within its elastic limit under the pressure of confined powder gases to transmit stress to outer cylinders that are under tension.  Concentric metal cylinders or wire windings are assembled to minimize the weight required to resist the pressure of powder gases pushing a projectile out of the barrel.  Built-up construction was the norm for guns mounted aboard 20th century Dreadnoughts and contemporary railway guns, coastal artillery, and siege guns through World War II.
Answer: Dreadnought