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top 10 words in brain distribution (in article): signal frequency design sound produce wine tower common time type |
top 10 words in brain distribution (in article): blade steel head handle design tool century size type shape |
top 10 words in brain distribution (not in article): power light water station animal train line locomotive radio drink |
top 10 words in brain distribution (not in article): iron cut city metal hair nail whip breast build bronze |
times more probable under bell 30 20 10 6 4 2.5 1.25 1 1.25 2.5 4 6 10 20 30 times more probable under screwdriver (words not in the model) | |
A bell'" is a simple sound-making device. The bell is a percussion instrument and an idiophone. Its form is usually an open-ended hollow drum which resonates upon being struck. The striking implement can be a tongue suspended within the bell, known as a "clapper", a small, free sphere enclosed within the body of the bell, or a separate mallet. Bells are usually made of cast metal, but small bells can also be made from ceramic or glass. Bells can be of all sizes: from tiny dress accessories to church bells weighing many tons. Church and temple bells. In the Western world, its most classical form is a church bell or town bell, which is hung within a tower and sounded by having the entire bell swung by ropes, whereupon an internal hinged clapper strikes the body of the bell (called a free-swinging bell). A set of bells, hung in a circle for change ringing, is known as a ring of bells. In the Eastern world, the traditional forms of bells are temple and palace bells, small ones being rung by a sharp rap with a stick, and very large ones rung by a blow from the outside by a large swinging beam. The striking technique is employed worldwide for some of the largest tower-borne bells, because swinging the bells themselves could damage their towers. In the Roman Catholic Church and among some High Lutherans and Anglicans, small hand-held bells, called Sanctus or sacring bells, are often rung by a server at Mass when the priest holds high up first the host, and then the chalice immediately after he has said the words of consecration over them (the moment known as the Elevation). This serves to indicate to the congregation that the bread and wine have just been transformed into the body and blood of Christ (see transubstantiation), or, in the alternative Reformation teaching, that Christ is now bodily present in the elements, and that what the priest is holding up for them to look at is Christ himself (see consubstantiation). Japanese religious bells. Japanese Shintoist and Buddhist bells are used in religious ceremonies. "Suzu", a homophone meaning both "cool and refreshing," are spherical bells which contain metal pellets that produce sound from the inside. The hemispherical bell is the "Kane" bell, which is struck on the outside. See also Kane (musical instrument). Buddhist bells. Buddhist bells are used in religious ceremonies. Bell construed as a cause for war. On January 15, 1602 ("Keichō 7"), a fire broke out at Hōkō-ji, Buddhist temple complex in Kyoto. The great image of the Buddha and the structure housing the statue, the "Daibutsu-den", were both consumed by the flames. In 1610, Toyotomi Hideyori decided to sponsor rebuilding the Hōkō-ji and he also decided to order a great bell cast in bronze. On August 24, 1614 ("Keichō 19"), the huge new bronze bell was cast successfully. Dedication ceremonies were scheduled, but at the last minute, Tokugawa Ieyasu forbade the ceremonies to take place because he construed inscriptions on the bell to have been a personal affront: This contrived dispute led to the, which was a series of battles between armies of the Tokugawa shogunate and the samurai of the Toyotomi clan. The siege lasted through 1615. It is conventionally divided into two stages: the Winter Campaign and the Summer Campaign. In the end, the total destruction of the Toyotomi eliminated the last major opposition to the shogunate which would come to dominate Japan for the next 250 years. Bellmaking. The process of casting bells is called bellmaking or bellfounding, and in Europe dates to the 4th or 5th century. The traditional metal for these bells is a bronze of about 23% tin. Known as "bell metal", this alloy is also the traditional alloy for the finest Turkish and Chinese cymbals. Other materials sometimes used for large bells include brass and iron. Bells are always cast mouth down. Bells are made to exact formulas, so that given the diameter it is possible to calculate every dimension, and its musical note, or tone. The frequency of a bell's note in Hz varies with the square of its thickness, and inversely with its diameter. Much experimentation has been devoted to determining the exact shape that will give the best tone. The thickness of a church bell at its thickest part, called the 'sound bow' is usually one thirteenth its diameter. If the bell is mounted as cast, it is called a "maiden bell" while "tuned bells" are worked after casting to produce a precise note. Bell towers. Bells are also associated with clocks, indicating the hour by ringing. Indeed, the word "clock" comes from the Latin word "cloca", meaning bell. Clock towers or bell towers can be heard over long distances which was especially important in the time when clocks were too expensive for widespread use. In the case of clock towers and grandfather clocks, a particular sequence of tones may be played to represent the hour. One common pattern is called the "Westminster Quarters," a sixteen-note pattern named after the Palace of Westminster which popularized it as the measure used by "Big Ben". Bells as musical instruments. Some bells are used as musical instruments, such as carillons, (clock) chimes, or ensembles of bell-players, called bell choirs, using hand-held bells of varying tones. A "ring of bells" is a set of 4 to twelve bells or more used in change ringing, a particular method of ringing bells in patterns. A peal in changing ringing may have bells playing for several hours, playing 5,000 or more patterns without a break or repetition.. Ancient Chinese bells. The ancient Chinese bronze chime bells called bianzhong or (鐘) are among the highest achievements of Chinese bronze casting technology. These chime bells were used as polyphonic musical instruments and some of these bells have been dated at between 2000 to 3600 years old. The secret of the design and the method of casting zhong bells, which was known only to the Chinese in antiquity, was lost in later generations. It was not fully rediscovered and understood until 1978, when a complete ceremonial set of 65 "zhong" bells was found in a near-perfect state of preservation during the excavation of the of Marquis Yi, who died ca. 430BCE. Yi was ruler of Zeng, one of the Warring States which at the time of his | The screwdriver'" is a device specifically designed to insert and tighten, or to loosen and remove, screws. The screwdriver is made up of a head or tip, which engages with a screw, a mechanism to apply torque by rotating the tip, and some way to position and support the screwdriver. A typical hand screwdriver comprises an approximately cylindrical handle of a size and shape to be held by a human hand, and an axial shaft fixed to the handle, the tip of which is shaped to fit a particular type of screw. The handle and shaft allow the screwdriver to be positioned and supported and, when rotated, to apply torque. Screwdrivers are made in a variety of shapes, and the tip can be rotated manually or by an electric or other motor. A screw has a head with a contour such that an appropriate screwdriver tip can be engaged in it in such a way that the application of sufficient torque to the screwdriver will cause the screw to rotate. History. Gunsmiths still refer to a screwdriver as a "turnscrew", under which name it is an important part of a set of pistols. The name was common in earlier centuries, used by cabinet makers and shipwrights and perhaps other trades. The Cabinet-Maker's screwdriver is one of the longest-established handle forms, somewhat oval or elipsoid in cross section. This is variously attributed to improving grip or preventing the tool rolling off the bench, but there is no reason to suppose these are not rationalisations. The shape has been popular for a couple of hundred years. It is usually associated with a plain head for slotted screws, but has been used with many head forms. "See Also: "The History of Screws Types and variations. There are many types of screw heads, of which the most common are the slotted, Phillips, PoziDriv SupaDriv (crosspoint), Robertson, TORX, and Allen (hex). Screwdrivers come in a large variety of sizes to match those of screws, from tiny jeweler's screwdrivers up. If a screwdriver that is not the right size and type for the screw is used, it is likely that the screw will be damaged in the process of tightening it. This is less important for PoziDriv and SupaDriv, which are designed specifically to be more tolerant of size mismatch. When tightening a screw with force, it is important to press the head hard into the screw, again to avoid damaging the screw. Some manual screwdrivers have a ratchet action whereby the screwdriver blade is locked to the handle for clockwise rotation, but uncoupled for counterclockwise rotation when set for tightening screws; and vice versa for loosening. Many screwdriver designs have a handle with detachable head (the part of the screwdriver which engages with the screw), called "bits" as with drill bits, allowing a set of one handle and several heads to be used for a variety of screw sizes and types. This kind of design has allowed the development of electrically powered screwdrivers, which, as the name suggests, use an electric motor to rotate the bit. In such cases the terminology for power drills is used, e.g. "shank" or "collet". Some drills can also be fitted with screwdriver heads. Manual screw drivers with a spiral ratchet'" mechanism to turn pressure (linear motion) into rotational motion also exist, and predate electric screwdrivers. The user pushes the handle toward the workpiece, causing a pawl in a spiral groove to rotate the shank and the removable bit. The ratchet can be set to rotate left or right with each push, or can be locked so that the tool can be used like a conventional screwdriver. Once very popular, these spiral ratchet drivers, using proprietary bits, have been largely discontinued by manufacturers such as Stanley, although one can still find them at vintage tool auctions. Companies such as Lara Specialty Tools now offer a modernized version that uses standard 1 /4-inch hex shank power tool bits. Since a variety of drill bits are available in this format, it allows the tool to do double duty as a "push drill". Many modern electrical appliances, if they contain screws at all, use screws with heads other than the typical slotted or Phillips styles. TORX is one such pattern that has become very widespread. The main cause of this trend is manufacturing efficiency: TORX and other types are designed so the driver will not slip out of the fastener as will a Phillips driver. (Slotted screws are rarely used in mass-produced devices, since the driver is not inherently centered on the fastener). A benefit disadvantage of non-typical fasteners (depending on your point of view) is that it can be more difficult for users of a device to disassemble it than if more-common head types were used, but TORX and other drivers are widely available. Specialized patterns of security screws are also used, such as the Gamebit head style used in all Nintendo consoles, though drivers for most security heads are, again, readily available. While screwdrivers are designed for the above functions, they are commonly also used as improvised substitutes for pry bars, levers, and hole punches, as well as other tools. There is no such thing as a "left-handed screwdriver", as the device can easily be wielded in either hand. To be sent on an errand to find a left-handed screwdriver is often a test of stupidity, or is used as a metaphor for something useless. The term "Birmingham screwdriver" is used jokingly in the UK to denote a hammer or sledgehammer. The handle and shaft of screwdrivers have changed considerably over time. The design is influenced by both purpose and manufacturing requirements. The "Perfect Handle" screwdriver was first manufactured by HD Smith & Company that operated from 1850 to 1900. Many manufacturers adopted this handle design world wide. The "Flat Bladed" screwdriver was another design composed of drop forged steel with riveted wood handles? Among slotted screwdrivers, there are a couple of major variations at the blade or bit end involving the profile of the blade as viewed face-on. The more common type is sometimes referred to as keystone'", where the blade profile is slightly flared before tapering off at the end. To maximize access in space-restricted applications, the same edges for the "'cabinet'" variety, in contrast, are straight and parallel, meeting the end of the blade at a right angle. |