|
Pará-class Monitor
The ''Pará''-class monitors were a group of six wooden-hulled ironclad monitors named after Brazilian provinces and built in Brazil for the Imperial Brazilian Navy during the Paraguayan War in the late 1860s. The first three ships finished, , and , participated in the Passage of Humaitá in February 1868. Afterwards the remaining ships joined the first three and they all provided fire support for the army for the rest of the war. The ships were split between the newly formed Upper Uruguay ( pt, Alto Uruguai) and Mato Grosso Flotillas after the war. ''Alagoas'' was transferred to Rio de Janeiro in the 1890s and participated in the Fleet Revolt of 1893–94. Design and description The ''Pará''-class river monitors were designed to meet the need of the Brazilian Navy for small, shallow-draft armored ships capable of withstanding heavy fire during the Paraguayan War, which saw Argentina and Brazil allied against Paraguay. The two foreign-built river monitors already in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rio De Janeiro
Rio de Janeiro ( , , ; literally 'River of January'), or simply Rio, is the capital of the state of the same name, Brazil's third-most populous state, and the second-most populous city in Brazil, after São Paulo. Listed by the GaWC as a beta global city, Rio de Janeiro is the sixth-most populous city in the Americas. Part of the city has been designated as a World Heritage Site, named "Rio de Janeiro: Carioca Landscapes between the Mountain and the Sea", on 1 July 2012 as a Cultural Landscape. Founded in 1565 by the Portuguese, the city was initially the seat of the Captaincy of Rio de Janeiro, a domain of the Portuguese Empire. In 1763, it became the capital of the State of Brazil, a state of the Portuguese Empire. In 1808, when the Portuguese Royal Court moved to Brazil, Rio de Janeiro became the seat of the court of Queen Maria I of Portugal. She subsequently, under the leadership of her son the prince regent João VI of Portugal, raised Brazil to the dignity of a k ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Paraguay
Paraguay (; ), officially the Republic of Paraguay ( es, República del Paraguay, links=no; gn, Tavakuairetã Paraguái, links=si), is a landlocked country in South America. It is bordered by Argentina to the south and southwest, Brazil to the east and northeast, and Bolivia to the northwest. It has a population of seven million, nearly three million of whom live in the capital and largest city of Asunción, and its surrounding metro. Although one of only two landlocked countries in South America (Bolivia is the other), Paraguay has ports on the Paraguay and Paraná rivers that give exit to the Atlantic Ocean, through the Paraná-Paraguay Waterway. Spanish conquistadores arrived in 1524, and in 1537, they established the city of Asunción, the first capital of the Governorate of the Río de la Plata. During the 17th century, Paraguay was the center of Jesuit missions, where the native Guaraní people were converted to Christianity and introduced to European culture. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rifled Muzzle Loader
A rifled muzzle loader in the forecastle of HMS Gannet (1878) ">HMS_Gannet_(1878).html" ;"title="forecastle of HMS Gannet (1878)">forecastle of HMS Gannet (1878) A rifled muzzle loader (RML) is a type of large artillery piece invented in the mid-19th century. In contrast to Smoothbore, smooth bore cannon which preceded it, the rifling of the gun barrel allowed much greater accuracy and penetration as the spin induced to the shell gave it directional stability. Typical guns weighed 18 tonnes with 10-inch-diameter bores, and were installed in forts and ships. This new gun and the rifled breech loader (RBL) generated a huge arms race in the late 19th century, with rapid advances in fortifications and ironclad warships. Royal Navy experience The largest rifled muzzle-loader carried on a warship was the 17.7-inch, 100-ton Elswick of the 1870s, four of which were installed in each of the Italian battleships '' Duilio'' and ''Enrico Dandolo'' (launched in 1872). The Royal Navy at ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
70-pounder Whitworth Naval Gun
The 70-pounder Whitworth naval gun was designed by Joseph Whitworth during the 1860s. It was a rifled muzzle loader and used his hexagonal, rifled-bore design. Principle The gun used polygonal rifling, a principle invented by Whitworth in 1853. The concept was to use the hexagon to impart a very rapid spin to the projectile. The method of manufacturing the rifling was thus described by the Report of the Armstrong & Whitworth Committee of the British War Office (1866): may be described in general terms as a hexagonal bore with a rapid twist, although, strictly speaking, the bore is not hexagonal, but has 24 surfaces. The gun is, in the first instance, bored out cylindrically; a part of this original bore is left in the centre of each side of the hexagon, making six surfaces, then there are the coming out sides of the hexagon which give six more surfaces, and the going in sides giving also six surfaces, and lastly, the rounding off of the angles, which give six more, making 2 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marine Steam Engine
A marine steam engine is a steam engine that is used to power a ship or boat. This article deals mainly with marine steam engines of the reciprocating type, which were in use from the inception of the steamboat in the early 19th century to their last years of large-scale manufacture during World War II. Reciprocating steam engines were progressively replaced in marine applications during the 20th century by steam turbines and marine diesel engines. History The first commercially successful steam engine was developed by Thomas Newcomen in 1712. The steam engine improvements brought forth by James Watt in the later half of the 18th century greatly improved steam engine efficiency and allowed more compact engine arrangements. Successful adaptation of the steam engine to marine applications in England would have to wait until almost a century after Newcomen, when Scottish engineer William Symington built the world's "first practical steamboat", the '' Charlotte Dundas'', in 1802. Ri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freeboard (nautical)
In sailing and boating, a vessel's freeboard is the distance from the waterline to the upper deck level, measured at the lowest point of sheer where water can enter the boat or ship. In commercial vessels, the latter criterion measured relative to the ship's load line, regardless of deck arrangements, is the mandated and regulated meaning. In yachts, a low freeboard is often found on racing boats, for increased speed (by reducing weight and therefore drag). A higher freeboard will give more room in the cabin, but will increase weight and drag, compromising speed. A higher freeboard, such as used on ocean liners, also helps weather waves and so reduce the likelihood of being washed over by full water waves. A low-freeboard vessel is susceptible to taking in water in rough seas. Freighter ships and warships use high freeboard designs to increase internal volume, which also allows them to satisfy International Maritime Organization (IMO) damage stability regulations, due to in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Draft (ship)
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 more heavily a vessel is loaded, the deeper it sinks into the water, and the greater its draft. After construction, the shipyard creates a table showing how much water the vessel displaces based on its draft and the density of the water (salt or fresh). The draft can also be used to determine the weight of cargo on board by calculating the total displacement of water, accounting for the content of the ship's bunkers, and using Archimedes' principle. The closely related term "trim" is defined as the difference between the forward and aft ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beam (nautical)
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. Generally speaking, the wider the beam of a ship (or boat), the more initial stability it has, at the expense of secondary stability in the event of a capsize, where more energy is required to right the vessel from its inverted position. A ship that heels on her ''beam ends'' has her deck beams nearly vertical. Typical values Typical length-to-beam ratios ( aspect ratios) for small sailboats are from 2:1 (dinghies to trailerable sailboats around ) to 5:1 (racing sailboats over ). Large ships have widely varying beam ratios, some as large as 20:1. Rowing shells designed for flatwater racing may have length to beam ratios as high as 30:1, while a cor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Length Overall
__NOTOC__ Length overall (LOA, o/a, o.a. or oa) 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 (for example, £2.50 per metre LOA). LOA is usually measured on the hull alone. For sailing ships, this may ''exclude'' the bowsprit and other fittings added to the hull. This is how some racing boats and tall ships use the term LOA. However, other sources may include bowsprits in LOA. Confusingly, LOA has different meanings. "Sparred length", "Total length including bowsprit", "Mooring length" and "LOA including bowsprit" are other expressions that might indicate the full length of a sailing ship. LOD Often used to distinguish between the length of a vessel including projections (e.g. bow sprits, etc.) from the length of the hull itself, the Length on Deck or LOD is often repor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Biofouling
Biofouling or biological fouling is the accumulation of microorganisms, plants, algae, or small animals where it is not wanted on surfaces such as ship and submarine hulls, devices such as water inlets, pipework, grates, ponds, and rivers that cause degradation to the primary purpose of that item. Such accumulation is referred to as '' epibiosis'' when the host surface is another organism and the relationship is not parasitic. Since biofouling can occur almost anywhere water is present, biofouling poses risks to a wide variety of objects such as boat hulls and equipment, medical devices and membranes, as well as to entire industries, such as paper manufacturing, food processing, underwater construction, and desalination plants. Anti-fouling is the ability of specifically designed materials (such as toxic biocide paints, or non-toxic paints) to remove or prevent biofouling. The buildup of biofouling on marine vessels poses a significant problem. In some instances, the hull struc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muntz Metal
Muntz metal (also known as yellow metal) is an alpha-beta brass alloy composed of approximately 60% copper, 40% zinc and a trace of iron. It is named after George Fredrick Muntz, a metal-roller of Birmingham, England, who commercialised the alloy following his patent of 1832. The alloy must be worked hot and is used today for corrosion-resistant machine parts. Alpha-beta (also called duplex) metals contain both the α and β phases. The α phase refers to a crystal structure that is face-centered cubic, while the β phase is body-centered cubic. Its original application was as a replacement for copper sheathing on the bottom of boats, as it maintained the anti-fouling abilities of the pure copper at around two thirds of the price. It became the material of choice for this application and Muntz made his fortune. It was found that copper would gradually leach from the alloy in sea water, poisoning any organism that attempted to attach itself to a hull sheathed in the metal. Thus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Naval Ram
A ram was a weapon fitted to varied types of ships, dating back to antiquity. The weapon comprised an underwater prolongation of the bow of the ship to form an armoured beak, usually between 2 and 4 meters (6–12 ft) in length. This would be driven into the hull of an enemy ship to puncture, sink or disable it. Ancient rams It was possibly developed in late Bronze age Egypt, but it only became widely used in later Iron age Mediterranean galleys. The ram was a naval weapon in the Greek/Roman antiquity and was used in such naval battles as Salamis and Actium. Naval warfare in the Mediterranean rarely used sails, and the use of rams specifically required oarsmen rather than sails in order to maneuver with accuracy and speed, and particularly to reverse the movement of a ramming ship to disentangle it from its sinking victim, lest it be pulled down when its victim sank. The Athenians were especially known for their ''diekplous'' and '' periplous'' tactics that disabled enemy ships ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
.svg "Click for more on -> Paraguay")
