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Depth Gauge
A depth gauge is an instrument for measuring depth below a reference surface. They include depth gauges for underwater diving and similar applications, and engineering instruments used to measure the depth of holes and indentations from a reference surface. A diving depth gauge is a pressure gauge that displays the equivalent depth below the free surface in water. The relationship between depth and pressure is linear and accurate enough for most practical purposes, and for many purposes, such as diving, it is actually the pressure that is important. It is a piece of diving equipment used by underwater divers, submarines and submersibles. Most modern diving depth gauges have an electronic mechanism and digital display. Earlier types used a mechanical mechanism and analogue display. Digital depth gauges used by divers commonly also include a timer showing the interval of time that the diver has been submerged. Some show the diver's rate of ascent and descent, which can be is u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Depth Gauge
A depth gauge is an instrument for measuring depth below a reference surface. They include depth gauges for underwater diving and similar applications, and engineering instruments used to measure the depth of holes and indentations from a reference surface. A diving depth gauge is a pressure gauge that displays the equivalent depth below the free surface in water. The relationship between depth and pressure is linear and accurate enough for most practical purposes, and for many purposes, such as diving, it is actually the pressure that is important. It is a piece of diving equipment used by underwater divers, submarines and submersibles. Most modern diving depth gauges have an electronic mechanism and digital display. Earlier types used a mechanical mechanism and analogue display. Digital depth gauges used by divers commonly also include a timer showing the interval of time that the diver has been submerged. Some show the diver's rate of ascent and descent, which can be is u ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metre Sea Water
The metre (or meter) sea water (msw) is a metric unit of pressure used in underwater diving. It is defined as one tenth of a bar. The unit used in the US is the foot sea water (fsw), based on standard gravity and a sea-water density of 64 lb/ft3. According to the US Navy Diving Manual, one fsw equals 0.30643 msw, , or , though elsewhere it states that 33 fsw is (one atmosphere), which gives one fsw equal to about 0.445 psi.Page 2-12. The msw and fsw are the conventional units for measurement of diver pressure exposure used in decompression tables and the unit of calibration for pneumofathometers and hyperbaric chamber pressure gauges. Feet of sea water One atmosphere is approximately equal to 33 feet of sea water or 14.7 psi, which gives 4.9/11 or about 0.445 psi per foot. Atmospheric pressure may be considered constant at sea level, and minor fluctuations caused by the weather are usually ignored. Pressures measured in fsw and msw are gauge pressure, rel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pressure Measurement
Pressure measurement is the measurement of an applied force by a fluid (liquid or gas) on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pressure and vacuum. Instruments used to measure and display pressure mechanically are called pressure gauges, vacuum gauges or compound gauges (vacuum & pressure). The widely used Bourdon gauge is a mechanical device, which both measures and indicates and is probably the best known type of gauge. A vacuum gauge is used to measure pressures lower than the ambient atmospheric pressure, which is set as the zero point, in negative values (for instance, −1 bar or −760 mmHg equals total vacuum). Most gauges measure pressure relative to atmospheric pressure as the zero point, so this form of reading is simply referred to as "gauge pressure". However, anything greater than total vacuum is technically a form of pressure. For very low press ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Manometer Anim 02
Pressure measurement is the measurement of an applied force by a fluid (liquid or gas) on a surface. Pressure is typically measured in units of force per unit of surface area. Many techniques have been developed for the measurement of pressure and vacuum. Instruments used to measure and display pressure mechanically are called pressure gauges, vacuum gauges or compound gauges (vacuum & pressure). The widely used Bourdon gauge is a mechanical device, which both measures and indicates and is probably the best known type of gauge. A vacuum gauge is used to measure pressures lower than the ambient atmospheric pressure, which is set as the zero point, in negative values (for instance, −1 bar or −760 mmHg equals total vacuum). Most gauges measure pressure relative to atmospheric pressure as the zero point, so this form of reading is simply referred to as "gauge pressure". However, anything greater than total vacuum is technically a form of pressure. For very low pressur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Graduation (instrument)
A graduation is a marking used to indicate points on a visual scale, which can be present on a container, a measuring device, or the axes of a line plot, usually one of many along a line or curve, each in the form of short line segments perpendicular to the line or curve. Often, some of these line segments are longer and marked with a numeral, such as every fifth or tenth graduation. The scale itself can be linear (the graduations are spaced at a constant distance apart) or nonlinear. Linear graduation of a scale occurs mainly (but not exclusively) on straight measuring devices, such as a rule or measuring tape, using units such as inches or millimetres. Graduations can also be spaced at varying spatial intervals, such as when using a logarithmic, for instance on a measuring cup, can vary in scale due to the container's non- cylindrical shape. Graduations along a curve Circular graduations of a scale occur on a circular arc or limb of an instrument. In some cases, non-circ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bar (unit)
The bar is a metric unit of pressure, but not part of the International System of Units (SI). It is defined as exactly equal to 100,000 Pa (100 kPa), or slightly less than the current average atmospheric pressure on Earth at sea level (approximately 1.013 bar). By the barometric formula, 1 bar is roughly the atmospheric pressure on Earth at an altitude of 111 metres at 15 °C. The bar and the millibar were introduced by the Norwegian meteorologist Vilhelm Bjerknes, who was a founder of the modern practice of weather forecasting. The International System of Units, despite previously mentioning the bar, now omits any mention of it.. The bar has been legally recognised in countries of the European Union since 2004.British Standard BS 350:2004 ''Conversion Factors for Units''. The US National Institute of Standards and Technology (NIST) deprecates its use except for "limited use in meteorology" and lists it as one of several units that "must not be introduced ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diving Bell
A diving bell is a rigid chamber used to transport divers from the surface to depth and back in open water, usually for the purpose of performing underwater work. The most common types are the open-bottomed wet bell and the closed bell, which can maintain an internal pressure greater than the external ambient. Diving bells are usually suspended by a cable, and lifted and lowered by a winch from a surface support platform. Unlike a submersible, the diving bell is not designed to move under the control of its occupants, nor to operate independently of its launch and recovery system. The wet bell is a structure with an airtight chamber which is open to the water at the bottom, that is lowered underwater to operate as a base or a means of transport for a small number of divers. Air is trapped inside the bell by pressure of the water at the interface. These were the first type of diving chamber, and are still in use in modified form. The closed bell is a pressure vessel for human ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Turtle (submersible)
''Turtle'' (also called ''American Turtle'') was the world's first submersible vessel with a documented record of use in combat. It was built in 1775 by American David Bushnell as a means of attaching Naval mine, explosive charges to ships in a harbor, for use against Royal Navy vessels occupying American harbors during the American Revolutionary War. Connecticut Governor Jonathan Trumbull recommended the invention to George Washington, who provided funds and support for the development and testing of the machine. Several attempts were made using ''Turtle'' to affix explosives to the undersides of British warships in New York Harbor in 1776. All failed, and her transport ship was sunk later that year by the British with the submarine aboard. Bushnell claimed eventually to have recovered the machine, but its final fate is unknown. Modern replicas of ''Turtle'' have been constructed and are on display in the Connecticut River Museum, the U.S. Navy's Submarine Force Library and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
David Bushnell
David Bushnell (August 30, 1740 – 1824 or 1826), of Westbrook, Connecticut, was an American inventor, a patriot, one of the first American combat engineers, a teacher, and a medical doctor. Bushnell invented the first submarine to be used in battle, as well as a floating mine triggered by contact. He was a veteran of the Revolutionary War. Early life David Bushnell was born in a secluded part of Saybrook, Connecticut on the 30th August, 1740 and baptized in 1743 into a farming family in what is now Westbrook, Connecticut where his parents Nehemiah Bushnell (1710 – d. bef 1762) and Sarah (Susan) Ingham Bushnell owned a farm. He was the first of five children born. Following the death of his father circa 1769, he sold his half interest in the family Westbrook farm to his brother Ezra and entered Yale College in 1771 at the relatively old age of 31. The ''Turtle'' submarine Bushnell is credited with creating the first submarine ever used in combat, while studying at Yale ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Haven, Connecticut
New Haven is a city in the U.S. state of Connecticut. It is located on New Haven Harbor on the northern shore of Long Island Sound in New Haven County, Connecticut and is part of the New York City metropolitan area. With a population of 134,023 as determined by the 2020 U.S. census, New Haven is the third largest city in Connecticut after Bridgeport and Stamford and the principal municipality of Greater New Haven, which had a total 2020 population of 864,835. New Haven was one of the first planned cities in the U.S. A year after its founding by English Puritans in 1638, eight streets were laid out in a four-by-four grid, creating the "Nine Square Plan". The central common block is the New Haven Green, a square at the center of Downtown New Haven. The Green is now a National Historic Landmark, and the "Nine Square Plan" is recognized by the American Planning Association as a National Planning Landmark. New Haven is the home of Yale University, New Haven's biggest taxpayer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Isaac Doolittle
Isaac Doolittle (August 3, 1721 – February 13, 1800) was an early American clockmaker, inventor, engineer, manufacturer, militia officer, entrepreneur, printer, politician, and brass, iron, and silver artisan. Doolittle was a watchmaker and clockmaker, known for making and selling at his shop in New Haven, Connecticut one of the first brass wheel hall clocks in America, where he also crafted and sold scientific instruments, and is regarded as "the first native practitioner" of silversmithing in the Connecticut Colony. He was also an engraver and printer of both legal forms and currency, and became the first American to design, manufacture, and sell a printing press in 1769. Somewhat late in life, he became a successful self-educated bell-foundryman, learning the difficult craft of casting large metal bells. Doolittle was an important figure in the religious life of Connecticut as an Episcopal Churchwarden and co-founder of Trinity Church on the Green in New Haven. Called a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Denis Papin
Denis Papin FRS (; 22 August 1647 – 26 August 1713) was a French physicist, mathematician and inventor, best known for his pioneering invention of the steam digester, the forerunner of the pressure cooker and of the steam engine. Early life and education Born in Chitenay ( Loir-et-Cher, Centre-Val de Loire Région), Papin attended a Jesuit school there. In 1661, he attended the University of Angers, from which he graduated with a medical degree in 1669. Career In 1673, Papin worked with Christiaan Huygens and Gottfried Leibniz in Paris, and became interested in using a vacuum to generate motive power. In 1675, he first visited London, where he worked with Robert Boyle from 1676 to 1679, publishing an account of his work in ''Continuation of New Experiments'' (1680). During this period, Papin invented the ''steam digester,'' a type of pressure cooker with a safety valve. He first addressed the Royal Society in 1679 on the subject of his digester, and remained mostly in Lond ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
