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Winch Sling
A winch is a mechanical device that is used to pull in (wind up) or let out (wind out) or otherwise adjust the tension of a rope or wire rope (also called "cable" or "wire cable"). In its simplest form, it consists of a spool (or drum) attached to a hand crank. Traditionally, winches on ships accumulated wire or rope on the drum; those that do not accumulate, and instead pass on the wire/rope (see yacht photo above), are called capstans. Despite this, sailboat capstans are most often referred to as winches. Winches are the basis of such machines as tow trucks, steam shovels and elevators. More complex designs have gear assemblies and can be powered by electric, hydraulic, pneumatic or internal combustion drives. It might include a solenoid brake and/or a mechanical brake or ratchet and pawl which prevents it unwinding unless the pawl is retracted. The rope may be stored on the winch. When trimming a line on a sailboat, the crew member turns the winch handle with one ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ratchet (device)
A ratchet (occasionally spelled rachet) is a mechanical device that allows continuous linear or rotary motion in only one direction while preventing motion in the opposite direction. Ratchets are widely used in machinery and tools. The word ''ratchet'' is also used informally to refer to a ratcheting socket wrench. __TOC__ Theory of operation A ratchet consists of a round gear or a linear rack with teeth, and a pivoting, spring-loaded finger called a ''pawl'' (or ''click'', in clocks and watches) that engages the teeth. The teeth are uniform but are usually asymmetrical, with each tooth having a moderate slope on one edge and a much steeper slope on the other edge. When the teeth are moving in the unrestricted (i.e. forward) direction, the pawl easily slides up and over the gently sloped edges of the teeth, with a spring forcing it (often with an audible 'click') into the depression between the teeth as it passes the tip of each tooth. When the teeth move in the opposite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Journal Of Hellenic Studies
''The Journal of Hellenic Studies'' is an annual peer-reviewed academic journal covering research in Hellenic studies. It also publishes reviews of recent books of importance to Hellenic studies. It was established in 1880 and is published by Cambridge University Press on behalf of the Society for the Promotion of Hellenic Studies. The editor-in-chief is Lin Foxhall (University of Liverpool). Editors The following persons have been editors-in-chief of the journal: *Percy Gardner, 1879-1895 *Ernest Arthur Gardner Ernest Arthur Gardner (16 March 186227 November 1939) was an English archaeologist. He was the director of the British School at Athens between 1887 and 1895. Early life Gardner was born in Clapton, London, England on 16 March 1862 to Thomas ..., 1897-1932 *Roger Brock, 2011-2016 *Douglas Cairns, 2016-2021 References External links * * Hathi Trust''Journal of Hellenic Studies'' 1880- Classics journals Publications established in 1880 English-language jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mechanics (Aristotle)
''Mechanics'' ( el, Μηχανικά; la, Mechanica), also called ''Mechanical Problems'' or ''Questions of Mechanics'', is a text traditionally attributed to Aristotle, but generally regarded as spurious. Thomas Winter has suggested that the author was Archytas. However, Michael Coxhead says that it is only possible to conclude that the author was one of the Peripatetics. During the Renaissance, an edition of this work was published by Francesco Maurolico. A Latin translation was made by Vettor Fausto, dedicated to Giovanni Badoer in 1517. See also *Aristotle's wheel paradox Aristotle's wheel paradox is a paradox or problem appearing in the Greek work ''Mechanica'', traditionally attributed to Aristotle. It states as follows: A wheel is depicted in two-dimensional space as two circles. Its larger, outer circle is tang ... Notes External links * Pseudo-Aristotle, ''Mechanica''- Greek text and English translation * Works by Aristotle Ancient Greek technology [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aristotle
Aristotle (; grc-gre, Ἀριστοτέλης ''Aristotélēs'', ; 384–322 BC) was a Greek philosopher and polymath during the Classical Greece, Classical period in Ancient Greece. Taught by Plato, he was the founder of the Peripatetic school of philosophy within the Lyceum (classical), Lyceum and the wider Aristotelianism, Aristotelian tradition. His writings cover many subjects including Physics (Aristotle), physics, biology, zoology, metaphysics, logic, ethics, aesthetics, Poetics (Aristotle), poetry, theatre, music, rhetoric, psychology, linguistics, economics, politics, meteorology, History of geology, geology, and government. Aristotle provided a complex synthesis of the various philosophies existing prior to him. It was above all from his teachings that Western culture, the West inherited its intellectual lexicon, as well as problems and methods of inquiry. As a result, his philosophy has exerted a unique influence on almost every form of knowledge in the West a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hoist (device)
A hoist is a device used for lifting or lowering a load by means of a drum or lift-wheel around which rope or chain wraps. It may be manually operated, electrically or pneumatically driven and may use chain, fiber or wire rope as its lifting medium. The most familiar form is an elevator, the car of which is raised and lowered by a hoist mechanism. Most hoists couple to their loads using a lifting hook. Today, there are a few governing bodies for the North American overhead hoist industry which include the Hoist Manufactures Institute, ASME, and the Occupational Safety and Health Administration. HMI is a product counsel of the Material Handling Industry of America consisting of hoist manufacturers promoting safe use of their products. Types The word “hoist” is used to describe many different types of equipment that lift and lower loads. For example, many people use “hoist” to describe an elevator. The information contained here pertains specially to overhead, co ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Assyria
Assyria (Neo-Assyrian cuneiform: , romanized: ''māt Aššur''; syc, ܐܬܘܪ, ʾāthor) was a major ancient Mesopotamian civilization which existed as a city-state at times controlling regional territories in the indigenous lands of the Assyrians from the 21st century BC to the 14th century BC, then to a territorial state, and eventually an empire from the 14th century BC to the 7th century BC. Spanning from the early Bronze Age to the late Iron Age, modern historians typically divide ancient Assyrian history into the Early Assyrian ( 2600–2025 BC), Old Assyrian ( 2025–1364 BC), Middle Assyrian ( 1363–912 BC), Neo-Assyrian (911–609 BC) and post-imperial (609 BC– AD 630) periods, based on political events and gradual changes in language. Assur, the first Assyrian capital, was founded 2600 BC but there is no evidence yet discovered that the city was independent until the collapse of the Third Dynasty of Ur in the 21st century BC, when a line of independent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hellespont
The Dardanelles (; tr, Çanakkale Boğazı, lit=Strait of Çanakkale, el, Δαρδανέλλια, translit=Dardanéllia), also known as the Strait of Gallipoli from the Gallipoli peninsula or from Classical Antiquity as the Hellespont (; grc-x-classical, Ἑλλήσποντος, translit=Hellēspontos, lit=Sea of Helle), is a narrow, natural strait and internationally significant waterway in northwestern Turkey that forms part of the continental boundary between Asia and Europe and separates Asian Turkey from European Turkey. Together with the Bosporus, the Dardanelles forms the Turkish Straits. One of the world's narrowest straits used for international navigation, the Dardanelles connects the Sea of Marmara with the Aegean and Mediterranean seas while also allowing passage to the Black Sea by extension via the Bosporus. The Dardanelles is long and wide. It has an average depth of with a maximum depth of at its narrowest point abreast the city of Çanakka ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pontoon Bridge
A pontoon bridge (or ponton bridge), also known as a floating bridge, uses floats or shallow- draft boats to support a continuous deck for pedestrian and vehicle travel. The buoyancy of the supports limits the maximum load that they can carry. Most pontoon bridges are temporary and used in wartime and civil emergencies. There are permanent pontoon bridges in civilian use that can carry highway traffic. Permanent floating bridges are useful for sheltered water crossings if it is not considered economically feasible to suspend a bridge from anchored piers. Such bridges can require a section that is elevated or can be raised or removed to allow waterborne traffic to pass. Pontoon bridges have been in use since ancient times and have been used to great advantage in many battles throughout history, such as the Battle of Garigliano, the Battle of Oudenarde, the crossing of the Rhine during World War II, the Iran–Iraq War's Operation Dawn 8, and most recently, in the 2022 Ru ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Histories (Herodotus)
The ''Histories'' ( el, Ἱστορίαι, ; also known as ''The History'') of Herodotus is considered the founding work of history in Western literature. Written around 430 BC in the Ionic dialect of classical Greek, ''The Histories'' serves as a record of the ancient traditions, politics, geography, and clashes of various cultures that were known in Greece, Western Asia and Northern Africa at that time. Although not a fully impartial record, it remains one of the West's most important sources regarding these affairs. Moreover, it established the genre and study of history in the Western world (despite the existence of historical records and chronicles beforehand). ''The'' ''Histories'' also stands as one of the earliest accounts of the rise of the Persian Empire, as well as the events and causes of the Greco-Persian Wars between the Persian Empire and the Greek city-states in the 5th century BC. Herodotus portrays the conflict as one between the forces of slavery (the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greco-Persian Wars
The Greco-Persian Wars (also often called the Persian Wars) were a series of conflicts between the Achaemenid Empire and Greek city-states that started in 499 BC and lasted until 449 BC. The collision between the fractious political world of the Greeks and the enormous empire of the Persians began when Cyrus the Great conquered the Greek-inhabited region of Ionia in 547 BC. Struggling to control the independent-minded cities of Ionia, the Persians appointed tyrants to rule each of them. This would prove to be the source of much trouble for the Greeks and Persians alike. In 499 BC, the tyrant of Miletus, Aristagoras, embarked on an expedition to conquer the island of Naxos, with Persian support; however, the expedition was a debacle and, preempting his dismissal, Aristagoras incited all of Hellenic Asia Minor into rebellion against the Persians. This was the beginning of the Ionian Revolt, which would last until 493 BC, progressively drawing more regions of Asia Minor into ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Herodotus Of Halicarnassus
Herodotus ( ; grc, , }; BC) was an ancient Greek historian and geographer from the Greek city of Halicarnassus, part of the Persian Empire (now Bodrum, Turkey) and a later citizen of Thurii in modern Calabria (Italy). He is known for having written the ''Histories'' – a detailed account of the Greco-Persian Wars. Herodotus was the first writer to perform systematic investigation of historical events. He is referred to as " The Father of History", a title conferred on him by the ancient Roman orator Cicero. The ''Histories'' primarily cover the lives of prominent kings and famous battles such as Marathon, Thermopylae, Artemisium, Salamis, Plataea, and Mycale. His work deviates from the main topics to provide a cultural, ethnographical, geographical, and historiographical background that forms an essential part of the narrative and provides readers with a wellspring of additional information. Herodotus has been criticized for his inclusion of "legends and fanciful ac ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
