"carried out the experiment, and found that Pascal's predictions had been correct. The mercury barometer stood lower the higher one went. The concept that decreasing atmospheric pressure predicts stormy weather, postulated by Lucien Vidi, provides the theoretical basis for a weather prediction device called a ""weather glass"" or a ""Goethe barometer"" (named for Johann Wolfgang Von Goethe, the renowned German writer and polymath who developed a simple but effective weather ball barometer using the principles developed by Torricelli). The French name, ""le baromètre Liègeois"", is used by some English speakers. This name reflects the origins of many early weather glasses"
"the kinetic energy of the molecules within air. A barometer measures atmospheric pressure, or the pressure exerted by the weight of the Earth's atmosphere above a particular location. An anemometer measures the wind speed and the direction the wind is blowing from at the site where it is mounted. A hygrometer measures the relative humidity at a location, which can then be used to compute the dew point. Radiosondes directly measure most of these quantities, except for wind, which is determined by tracking the radiosonde signal with an antenna or theodolite. Supplementing the radiosondes a network of aircraft collection is"
"pressure-measuring device, called a barometer may also be constructed from a sample of an ideal gas held at a constant temperature. A calorimeter is a device which is used to measure and define the internal energy of a system. A thermodynamic reservoir is a system which is so large that its state parameters are not appreciably altered when it is brought into contact with the system of interest. When the reservoir is brought into contact with the system, the system is brought into equilibrium with the reservoir. For example, a pressure reservoir is a system at a particular pressure, which"
"Microbarometer Microbarometers are sensitive barometers that can measure air pressure with high precision. Microbarometers typically have a resolution of microbars (μbar) or pascals (Pa), while ordinary barometers can only resolve in hectopascals (hPa) or millibars (mbar). Recording microbarometers, or microbarographs, distributed around the world are planned to be used to monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty (upon entry into force) by detecting the infrasound signature of a nuclear explosion, which can propagate for very long distances. By analyzing the data received at several of these monitoring stations, the location and yield of the explosion can be determined. A microbarometer"
"via photolithography or photochemical machining. Typical applications include miniaturized weather stations, electronic barometers and altimeters. A barometer can also be found in smartphones such as the Samsung Galaxy Nexus, Samsung Galaxy S3-S6, Motorola Xoom, Apple iPhone 6 smartphones, and Timex Expedition WS4 smartwatch, based on MEMS and piezoresistive pressure-sensing technologies. Inclusion of barometers on smartphones was originally intended to provide a faster GPS lock. However, third party researchers were unable to confirm additional GPS accuracy or lock speed due to barometric readings. The researchers suggest that the inclusion of barometers in smartphones may provide a solution to determining a user's"
"Barograph A barograph is a barometer that records the barometric pressure over time. Alexander Cumming, a watchmaker and mechanic, has a claim to having made the first effective recording barograph in the 1760s using an aneroid cell. Cumming created a series of barometrical clocks, including one for King George III. However, this type of design fell out of favour. Since the amount of movement that can be generated by a single aneroid is minuscule, up to seven aneroids (so called Vidie-cans) are often stacked ""in series"" to amplify their motion. This type of barograph was invented in 1844 by the"
"Barometric light Barometric light is a name for the light that is emitted by a mercury-filled barometer tube when the tube is shaken. The discovery of this phenomenon in 1675 revealed the possibility of electric lighting. The earliest barometers were simply glass tubes that were closed at one end and filled with mercury. The tube was then inverted and its open end was submerged in a cup of mercury. The mercury then drained out of the tube until the pressure of the mercury in the tube — as measured at the surface of the mercury in the cup — equaled"
"physicist and mathematician who discovered the principle of the barometer in 1644. The unit's name ""torr"" is written in lower case, while its symbol (""Torr"") is always written with upper-case initial; including in combinations with prefixes and other unit symbols, as in ""mTorr"" (millitorr) or ""Torr⋅L/s"" (torr-litres per second). The symbol (uppercase) should be used with prefix symbols (thus, mTorr and millitorr are correct, but mtorr and milliTorr are not). The torr is sometimes incorrectly denoted by the symbol ""T"", which is the SI symbol for the tesla, the unit measuring the strength of a magnetic field. Although frequently encountered,"
"can be made to increase or decrease the speed and new chart is attached. Barograph A barograph is a barometer that records the barometric pressure over time. Alexander Cumming, a watchmaker and mechanic, has a claim to having made the first effective recording barograph in the 1760s using an aneroid cell. Cumming created a series of barometrical clocks, including one for King George III. However, this type of design fell out of favour. Since the amount of movement that can be generated by a single aneroid is minuscule, up to seven aneroids (so called Vidie-cans) are often stacked ""in series"""
"the various schools of philosophy and arts thereby affecting wide social change and ultimately an enlightenment of humanity: The thermometer measures caloric (""thermo"" temperature). The barometer measures the weight (""baro"", weight) of the atmosphere; the electrometer measures electric conditions; the psychometer measures the soul (""psyche""). In the case of Psychometry, however, the measuring assumes a new character, as the object measured and the measuring instrument are the same psychic element, and its measuring power is not limited to the psychic as it was developed in the first experiments, but has appeared by successive investigation to manifest a wider and wider"
"used as a pressure altimeter would be able to resolve altitude differences on the order of centimeters, but for the presence of infrasonic noise such as microbaroms. Microbarometer Microbarometers are sensitive barometers that can measure air pressure with high precision. Microbarometers typically have a resolution of microbars (μbar) or pascals (Pa), while ordinary barometers can only resolve in hectopascals (hPa) or millibars (mbar). Recording microbarometers, or microbarographs, distributed around the world are planned to be used to monitor compliance with the Comprehensive Nuclear-Test-Ban Treaty (upon entry into force) by detecting the infrasound signature of a nuclear explosion, which can propagate"
"a variable volume container using a floating piston sampling device to minimize light end losses. A urinometer is a medical hydrometer designed for urinalysis. As urine's specific gravity is dictated by its ratio of solutes (wastes) to water, a urinometer makes it possible to quickly assess a patient's overall level of hydration. A barkometer is calibrated to test the strength of tanning liquors used in tanning leather. The state of charge of a lead-acid battery can be estimated from the density of the sulfuric acid solution used as electrolyte. A hydrometer calibrated to read specific gravity relative to water at"
"reading. A saccharometer is a hydrometer used for determining the amount of sugar in a solution, invented by Thomas Thomson. It is used primarily by winemakers and brewers, and it can also be used in making sorbets and ice-creams. The first brewers' saccharometer was constructed by Benjamin Martin (with distillation in mind), and initially used for brewing by James Baverstock Sr in 1770. Henry Thrale adopted its use and it was later popularized by John Richardson in 1784. It consists of a large weighted glass bulb with a thin stem rising from the top with calibrated markings. The sugar level"
"exactly equal to the liquid–air surface tension. Because surface tension manifests itself in various effects, it offers a number of paths to its measurement. Which method is optimal depends upon the nature of the liquid being measured, the conditions under which its tension is to be measured, and the stability of its surface when it is deformed. An old style mercury barometer consists of a vertical glass tube about 1 cm in diameter partially filled with mercury, and with a vacuum (called Torricelli's vacuum) in the unfilled volume (see diagram to the right). Notice that the mercury level at the"
"– the glass blowers of Liège, Belgium. The weather ball barometer consists of a glass container with a sealed body, half filled with water. A narrow spout connects to the body below the water level and rises above the water level. The narrow spout is open to the atmosphere. When the air pressure is lower than it was at the time the body was sealed, the water level in the spout will rise above the water level in the body; when the air pressure is higher, the water level in the spout will drop below the water level in the"
"a digital altimeter for their primary visual one, preferring the direct altitude readout of a numeric display. In aircraft, an aneroid barometer measures the atmospheric pressure from a static port outside the aircraft. Air pressure decreases with an increase of altitude—approximately 100 hectopascals per 800 meters or one inch of mercury per 1000 feet near sea level. The aneroid altimeter is calibrated to show the pressure directly as an altitude above mean sea level, in accordance with a mathematical model atmosphere defined by the International Standard Atmosphere (ISA). Older aircraft used a simple aneroid barometer where the needle made less"
"it is difficult to detect the difference between constantly rising air and constantly sinking air. A variometer is a very sensitive vertical speed indicator. The variometer indicates climb rate or sink rate with audio signals (beeps) and/or a visual display. These units are generally electronic, vary in sophistication, and often include an altimeter and an airspeed indicator. More advanced units often incorporate a barograph for recording flight data and/or a built-in GPS. The main purpose of a variometer is in helping a pilot find and stay in the 'core' of a thermal to maximize height gain, and conversely indicating when"
"Barometric formula The barometric formula, sometimes called the ""exponential atmosphere"" or ""isothermal atmosphere"", is a formula used to model how the pressure (or density) of the air changes with altitude. The pressure drops approximately by 11.3 Pa per meter in first 1000 meters above sea level. There are two different equations for computing pressure at various height regimes below 86 km (or 278,400 feet). The first equation is used when the value of standard temperature lapse rate is not equal to zero: The second equation is used when standard temperature lapse rate equals zero: where: Or converted to imperial units:"
"well-considered choice of durable materials like oak and borosilicate glass certainly play an important role in its continued longevity. Other attempts to copy the instrument have floundered due to the use of inferior material, a lack of constant supervision, pollution of the pipe system and other factors reducing durability. Bert Bolle Barometer The Bert Bolle Barometer is a large water barometer. At over 12.5 metres tall, it is recognized as the largest barometer in the world by The International Guinness Book of Records. The instrument was created in 1985 in the Netherlands; in 2007 it was reinstalled in the new"
"Barometer question The barometer question is an example of an incorrectly designed examination question demonstrating functional fixedness that causes a moral dilemma for the examiner. In its classic form, popularized by American test designer professor Alexander Calandra (1911–2006), the question asked the student to ""show how it is possible to determine the height of a tall building with the aid of a barometer."" The examiner was confident that there was one, and only one, correct answer, which is by calculating the difference in pressure at the top and bottom of the building. Contrary to the examiner's expectations, the student responded"
"to a sudden change in air pressure, such as from a cold front, without any actual change in altitude. A barometric altimeter, used along with a topographic map, can help to verify one's location. It is more reliable, and often more accurate, than a GPS receiver for measuring altitude; the GPS signal may be unavailable, for example, when one is deep in a canyon, or it may give wildly inaccurate altitudes when all available satellites are near the horizon. Because barometric pressure changes with the weather, hikers must periodically re-calibrate their altimeters when they reach a known altitude, such as"
"both as classic optical instruments and as electronic measurement devices with a digital display. In marine aquarium keeping, a refractometer is used to measure the salinity and specific gravity of the water. In the automobile industry, a refractometer is used to measure the coolant concentration and the pH value of the coolant oils for the CNC machining process. In homebrewing, a brewing refractometer is used to measure the specific gravity before fermentation to determine the amount of fermentable sugars which will potentially be converted to alcohol. Brix refractometers are often used by hobbyists for making preserves including jams, marmalades and"
"thermometers are empirical (laboratory tested and calibrated) as well as calculated based on a theoretical thermodynamic understanding of the components and phases involved. The Ti-in-biotite thermometer is solely empirical and not well understood thermodynamically. Various mineral assemblages rely more upon pressure than temperature; for example reactions which involve a large volume change. At high pressure, specific minerals assume lower volumes (therefore density increases, as the mass does not change) - it is these minerals which are good indicators of paleo-pressure. Geothermobarometry Geothermobarometry is the science of measuring the previous pressure and temperature history of a metamorphic or intrusive igneous rocks."
"— the louder the noise, the brighter the light. The art is a veritable Barometer of excitement for the ballpark."" Barometer (sculpture) Barometer is a 2013 sculpture by Devin Laurence Field, to be installed at the newly constructed Hillsboro Ballpark in Oregon, United States. The stainless steel sculpture, commissioned by the City of Hillsboro, stands tall at the stadium's entry plaza. Installation of the work began on June 10, 2013. ""Barometer"", commissioned by the City of Hillsboro for the newly constructed Hillsboro Ballpark, was designed by Northwest sculpture Devin Laurence Field. Field's design was chosen from twenty qualified candidates by"
"Aerometer An aerometer is an instrument designed to measure the density (among other parameters) of the air and some gases. The word aerometer (or Ärometer, from Ancient Greek ἀήρ -aer ""air"" and μέτρον -métron ""measure, scale"") refers to various types of devices for measuring or handling of gases. The instruments designated with this name can be used to find: the density, the flow, the amount or some other parameter of the air or a determined gas. Another instrument called areometer (from Ancient Greek ἀραιός -araiós ""lightness"" and μέτρον -métron ""measure, scale""), also known as hydrometer, used for measuring liquids density,"
"as noted by James Maxwell in 1872, asserts that it is possible to measure temperature. An idealized thermometer is a sample of an ideal gas at constant pressure. From the ideal gas law, the volume of such a sample can be used as an indicator of temperature; in this manner it defines temperature. Although pressure is defined mechanically, a pressure-measuring device called a barometer may also be constructed from a sample of an ideal gas held at a constant temperature. A calorimeter is a device which is used to measure and define the internal energy of a system. Some common"
"Bert Bolle Barometer The Bert Bolle Barometer is a large water barometer. At over 12.5 metres tall, it is recognized as the largest barometer in the world by The International Guinness Book of Records. The instrument was created in 1985 in the Netherlands; in 2007 it was reinstalled in the new Visitor Centre of Denmark, Western Australia and was removed from there in 2011. The Dutch writer and barometer specialist Bert Bolle (born 1947) designed and built the water barometer in 1985 as the focal point of the Barometer Museum, which he ran with his wife Ethne in the 18th-century"
"located at sea level and under fair weather conditions is moved to an altitude of 1,000 feet (305 m), about 1 inch of mercury (~35 hPa) must be added on to the reading. The barometer readings at the two locations should be the same if there are negligible changes in time, horizontal distance, and temperature. If this were not done, there would be a false indication of an approaching storm at the higher elevation. Aneroid barometers have a mechanical adjustment that allows the equivalent sea level pressure to be read directly and without further adjustment if the instrument is not"
"Sympiesometer A sympiesometer is a compact and lightweight type of barometer that was widely used on ships in the 19th century. The sensitivity of this barometer was also used to measure altitude. The sympiesometer consists of two parts. One is a traditional mercury thermometer that is needed to calculate the expansion or contraction of the fluid in the barometer proper. The other is the barometer, consisting of a J-shaped tube open at the lower end and closed at the top, with small reservoirs at both ends of the tube. The lower end of the J and its associated reservoir were"
"pressure"" (damage threshold) than an absolute scale. Absolute scales are typically used in science, deep vacuum measurements (where the fluctuating pressure of the atmosphere becomes a nuisance), aeronautics (where precise measurements of the atmosphere are needed to determine altitude), or lighting construction (where the relative pressure of the atmosphere is inconsequential), and are measured in units of ""atmospheres"" or torr. Barometers do measure absolute pressure by holding a vacuum at the top of the mercury column or one side of a diaphragm, but that vacuum is awkward to achieve and maintain. Thus, while the general public may be familiar with"
"Atmometer An ""atmometer or evaporimeter""' is a scientific instrument used for measuring the rate of water evaporation from a wet surface to the atmosphere. Atmometers are mainly used by farmers and growers to measure evapotranspiration (ET) rates of crops at any field location. Evapotranspiration is a measure of all of the water that evaporates from land surfaces plus the water that transpires from plant surfaces. Based on the amount of water that does evaporate and transpire, the user can water crops correspondingly, which results in less water use and possibly increased crop yields. Companies that currently sell atmometers include C&M"
"Bar (unit) The bar is a metric unit of pressure, but is not approved as part of the International System of Units (SI). It is defined as exactly equal to 100,000 Pa, which is slightly less than the current average atmospheric pressure on Earth at sea level. 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 Bureau of Weights and Measures (BIPM) lists the bar as one of the ""non-SI units [that authors] should have the freedom to use"", but has declined to"
"the mechanical linkage. The pressure altimeter, also known as the barometric altimeter, is used to determine changes in air pressure that occur as the aircraft's altitude changes. Pressure altimeters must be calibrated prior to flight to register the pressure as an altitude above sea level. The instrument case of the altimeter is airtight and has a vent to the static port. Inside the instrument, there is a sealed aneroid barometer. As pressure in the case decreases, the internal barometer expands, which is mechanically translated into a determination of altitude. The reverse is true when descending from higher to lower altitudes."