HMS Scythe (1918)

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.

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.

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.

In a navy, a rate, rating or bluejacket is a junior enlisted sailor who is not a warrant officer or commissioned officer. Depending on the country and navy that uses it, the exact term and the range of ranks that it refers to may vary.

The knot is a unit of speed equal to one nautical mile per hour, exactly 1.852 km/h. The ISO standard symbol for the knot is kn. The same symbol is preferred by the Institute of Electrical and Electronics Engineers (IEEE), while kt is also common, especially in aviation, where it is the form recommended by the International Civil Aviation Organization (ICAO). The knot is a non-SI unit. The knot is used in meteorology, and in maritime and air navigation. A vessel travelling at 1 knot along a meridian travels approximately one minute of geographic latitude in one hour.

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.

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.

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.

Clydebank is a town in West Dunbartonshire, Scotland. Situated on the north bank of the River Clyde, it borders the village of Old Kilpatrick to the west, and the Yoker and Drumchapel areas of the adjacent City of Glasgow immediately to the east. Depending on the definition of the town's boundaries, the suburban areas of Duntocher, Faifley and Hardgate either surround Clydebank to the north, or are its northern outskirts, with the Kilpatrick Hills beyond.

The Grand Fleet was the main battlefleet of the Royal Navy during the First World War. It was established in August 1914 and disbanded in April 1919. Its main base was Scapa Flow in the Orkney Islands.

HMS Exeter was the second and last York-class heavy cruiser built for the Royal Navy during the late 1920s. Aside from a temporary deployment with the Mediterranean Fleet during the Abyssinia Crisis of 1935–36, she spent the bulk of the 1930s assigned to the Atlantic Fleet or the North America and West Indies Station. When World War II began in September 1939, the cruiser was assigned to patrol South American waters against German commerce raiders. Exeter was one of three British cruisers that fought the German heavy cruiser Admiral Graf Spee, later that year in the Battle of the River Plate. She was severely damaged during the battle, and she was in the shipyard for over a year.

The Battle of the River Plate was fought in the South Atlantic on 13 December 1939 as the first naval battle of the Second World War. The Kriegsmarine heavy cruiser Admiral Graf Spee, commanded by Captain Hans Langsdorff, engaged a Royal Navy squadron, commanded by Commodore Henry Harwood, comprising the light cruisers HMS Ajax, HMS Achilles and the heavy cruiser HMS Exeter.

Cobh, known from 1849 until 1920 as Queenstown, is a seaport town on the south coast of County Cork, Ireland. With a population of around 13,000 inhabitants, Cobh is on the south side of Great Island in Cork Harbour and home to Ireland's only dedicated cruise terminal. Tourism in the area draws on the maritime and emigration legacy of the town.

John Cashmore Ltd was a company operating largely in Newport, Monmouthshire, Wales. It became best known for ship breaking and scrapping redundant British railway locomotives.

Newport is a city and county borough in Wales, situated on the River Usk close to its confluence with the Severn Estuary, 12 mi (19 km) northeast of Cardiff. With a population of 145,700 at the 2011 census, Newport is the third-largest authority with city status in Wales, and seventh most populous overall. Newport became a unitary authority in 1996 and forms part of the Cardiff-Newport metropolitan area. Newport was the site of the last large-scale armed insurrection in Great Britain, the Newport Rising of 1839. The population grew considerably during the 2021 census, rising to 159,587, the largest growth of a unitary authority in Wales.