HMS Tourmaline (1919)

The first R class were a class of 62 destroyers built between 1916 and 1917 for the Royal Navy. They were an improvement, specifically in the area of fuel economy, of the earlier Admiralty M-class destroyers. The most important difference was that the Admiralty R class had two shafts and geared turbines, compared with the three shafts and direct turbines of the Admiralty M class, but in appearance the R class could be distinguished from its predecessors by having the after 4-inch gun mounted in a bandstand. The Admiralty ordered the first two of this class of ships in May 1915. Another seventeen were ordered in July 1915, a further eight in December 1915, and a final twenty-three in March 1916.

HMS Rosalind was an R-class destroyer which served with the Royal Navy. The ship was launched by Thornycroft on 14 October 1916 as the first of five similar ships ordered from the yard. The design was used as the basis for five subsequent ships of the S-class also built by the company. Rosalind served as part of the Grand Fleet during the First World War, operating as an escort to other warships and in anti-submarine patrols alongside other destroyers. The vessel was sold to be broken up on 13 July 1926.

Length overall is the maximum length of a vessel's hull measured parallel to the waterline. This length is important while docking the ship. It is the most commonly used way of expressing the size of a ship, and is also used for calculating the cost of a marina berth.

Length between perpendiculars is the length of a ship along the summer load line from the forward surface of the stem, or main bow perpendicular member, to the after surface of the sternpost, or main stern perpendicular member. When there is no sternpost, the centerline axis of the rudder stock is used as the aft end of the length between perpendiculars.

The beam of a ship is its width at its widest point. The maximum beam (BMAX) is the distance between planes passing through the outer extremities of the ship, beam of the hull (BH) only includes permanently fixed parts of the hull, and beam at waterline (BWL) is the maximum width where the hull intersects the surface of the water.

The draft or draught of a ship's hull is the vertical distance between the waterline and the bottom of the hull (keel). The draught of the vessel is the maximum depth of any part of the vessel, including appendages such as rudders, propellers and drop keels if deployed. Draft determines the minimum depth of water a ship or boat can safely navigate. The related term air draft is the maximum height of any part of the vessel above the water.

The displacement or displacement tonnage of a ship is its weight. As the term indicates, it is measured indirectly, using Archimedes' principle, by first calculating the volume of water displaced by the ship, then converting that value into weight. Traditionally, various measurement rules have been in use, giving various measures in long tons. Today, tonnes are more commonly used.

John Brown and Company of Clydebank was a Scottish marine engineering and shipbuilding firm. It built many notable and world-famous ships including RMS Lusitania, RMS Aquitania, HMS Hood, HMS Repulse, RMS Queen Mary, RMS Queen Elizabeth and the Queen Elizabeth 2.

A funnel is the smokestack or chimney on a ship used to expel boiler steam and smoke or engine exhaust. They are also commonly referred to as stacks.

Fuel oil is any of various fractions obtained from the distillation of petroleum. Such oils include distillates and residues. Fuel oils include heavy fuel oil, marine fuel oil (MFO), bunker fuel, furnace oil (FO), gas oil (gasoil), heating oils, diesel fuel and others.

The forecastle is the upper deck of a sailing ship forward of the foremast, or, historically, the forward part of a ship with the sailors' living quarters. Related to the latter meaning is the phrase "before the mast" which denotes anything related to ordinary sailors, as opposed to a ship's officers.

The 2-pounder gun, officially the QF 2-pounder and universally known as the pom-pom, was a 40 mm (1.6 in) British autocannon, used as an anti-aircraft gun by the Royal Navy. The name came from the sound that the original models make when firing. This QF 2-pounder was not the same gun as the Ordnance QF 2-pounder, used by the British Army as an anti-tank gun and a tank gun, although they both fired 2 lb (0.91 kg), 40 mm (1.6 in) projectiles.

Laying the keel or laying down is the formal recognition of the start of a ship's construction. It is often marked with a ceremony attended by dignitaries from the shipbuilding company and the ultimate owners of the ship.

Ceremonial ship launching involves the performance of ceremonies associated with the process of transferring a vessel to the water. It is a nautical tradition in many cultures, dating back thousands of years, to accompany the physical process with ceremonies which have been observed as public celebration and a solemn blessing, usually but not always, in association with the launch itself.

The Atlantic Fleet was a naval fleet of the Royal Navy. It existed for two separate periods; 1909 until 1914, and then 1919 until 1932.

The C class was a group of twenty-eight light cruisers of the Royal Navy, and were built in a sequence of seven groups known as the Caroline class, the Calliope class, the Cambrian class, the Centaur class, the Caledon class, the Ceres class and the Carlisle class. They were built for the rough conditions of the North Sea, and proved to be rugged and capable vessels, despite being somewhat small and cramped.

A light cruiser is a type of small or medium-sized warship. The term is a shortening of the phrase "light armored cruiser", describing a small ship that carried armor in the same way as an armored cruiser: a protective belt and deck. Prior to this smaller cruisers had been of the protected cruiser model, possessing armored decks only. While lighter and smaller than other contemporary ships they were still true cruisers, retaining the extended radius of action and self-sufficiency to act independently around the world. Through their history they served in a variety of roles, primarily as convoy escorts and destroyer command ships, but also as scouts and fleet support vessels for battle fleets.

HMS Castor was one of the Cambrian subclass of the C class of light cruisers. She saw service during the First World War and the Russian Civil War.

The dreadnought was the predominant type of battleship in the early 20th century. The first of the kind, the Royal Navy's HMS Dreadnought, had such an effect when launched in 1906 that similar battleships built after her were referred to as "dreadnoughts", and earlier battleships became known as pre-dreadnoughts. Her design had two revolutionary features: an "all-big-gun" armament scheme, with an unprecedented number of heavy-calibre guns, and steam turbine propulsion. As dreadnoughts became a crucial symbol of national power, the arrival of these new warships renewed the naval arms race between the United Kingdom and Germany. Dreadnought races sprang up around the world, including in South America, lasting up to the beginning of 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 outclassed Dreadnought herself. 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 serving throughout World War II.

HMS Iron Duke was a dreadnought battleship of the Royal Navy, the lead ship of her class, named in honour of Arthur Wellesley, 1st Duke of Wellington. She was built by Portsmouth Dockyard, and her keel laid in January 1912. Launched ten months later, she was commissioned into the Home Fleet in March 1914 as the fleet flagship. She was armed with a main battery of ten 13.5-inch (343 mm) guns and was capable of a top speed of 21.25 knots.

Constantinople became the de facto capital of the Roman Empire upon its founding in 330, and became the de jure capital in AD 476 after the fall of Ravenna and the Western Roman Empire. It remained the capital of the Eastern Roman Empire, the Latin Empire (1204–1261), and the Ottoman Empire (1453–1922). Following the Turkish War of Independence, the Turkish capital then moved to Ankara. Officially renamed Istanbul in 1930, the city is today the largest city and financial centre of the Republic of Turkey (1923–present). It is also the largest city in Europe.

The Black Sea is a marginal mediterranean sea of the Atlantic Ocean lying between Europe and Asia, east of the Balkans, south of the East European Plain, west of the Caucasus, and north of Anatolia. It is bounded by Bulgaria, Georgia, Romania, Russia, Turkey, and Ukraine. The Black Sea is supplied by major rivers, principally the Danube, Dnieper, and Don. Consequently, while six countries have a coastline on the sea, its drainage basin includes parts of 24 countries in Europe.

HMS Tobago was an S-class destroyer which served with the Royal Navy during the Greco-Turkish War. Launched by Thornycroft on 15 July 1918, the vessel followed a design typical of the yard by being faster than the majority of the class, and also had better seakeeping properties thanks to a raised forecastle. The destroyer operated as part of the Grand Fleet for the last few weeks of the First World War, and, after the Armistice, joined the Mediterranean Fleet based in Malta. While serving in off the coast of Turkey, the ship hit a mine on 15 July 1920, exactly two years after being launched. Despite the relative youth of the vessel, the damage was deemed irrepairable and so Tobago returned to Malta and was sold for scrap on 9 February 1922.