When was the mercury thermometer invented?
List of Dutch inventions and innovations
Before there was the thermometer, there was the earlier and closely related thermoscope, best described as a thermometer without a temperature scale. A thermoscope only showed the differences in temperatures, for example, it could show something was getting hotter. However, the thermoscope did not measure all the data that a thermometer could, for example an exact temperature in degrees. What can be considered the first modern thermometer, the mercury thermometer with a standardized scale, was invented by German-Dutch scientist Daniel Gabriel Fahrenheit (who had settled in Amsterdam in 1701) in 1714. Fahrenheit invented the first truly accurate thermometer using mercury instead of alcohol and water mixtures. He began constructing his own thermometers in 1714, and it was in these that he used mercury for the first time.
Daniel Gabriel Fahrenheit
A pioneer of exact thermometry, he helped lay the foundations for the era of precision thermometry by inventing the mercury-in-glass thermometer (first practical, accurate thermometer) and Fahrenheit scale (first standardized temperature scale to be widely used). In other words, Fahrenheit's inventions ushered in the first revolution in the history of thermometry (branch of physics concerned with methods of temperature measurement). From the early 1710s until the beginnings of the electronic era, mercury-in-glass thermometers were among the most reliable and accurate thermometers ever invented.
History of continuous noninvasive arterial pressure
The first instrument which could measure the force of pulse with a mercury filled glass tube was developed by Jules Harrison in 1835. Jean Léonard Marie Poiseuille invented the first mercury “Hemodynameter”, a forerunner of the sphygmomanometer in 1821.
Mercury-in-glass thermometer
The thermometer was used by the originators of the Fahrenheit and Celsius scales.
Atmospheric thermometer
An atmospheric thermometer is a device that measures the temperature of the indoor or outdoor atmosphere. The most common type consists of a long tube that contains mercury or colored alcohol at the base, although there are also other kinds, such as spring and digital thermometers. When the atmospheric temperature rises, it causes the material inside the air thermometer to expand. Conversely, when the air gets colder, the material contracts and travels back down.Thermometers use temperature scales either Fahrenheit, Celsius, Kelvin, to provide a measure of heat in degrees.
Thermometer
The first physician that put thermometer measurements to clinical practice was Herman Boerhaave (1668–1738). In 1866, Sir Thomas Clifford Allbutt (1836–1925) invented a clinical thermometer that produced a body temperature reading in five minutes as opposed to twenty. In 1999, Dr. Francesco Pompei of the Exergen Corporation introduced the world's first temporal artery thermometer, a non-invasive temperature sensor which scans the forehead in about two seconds and provides a medically accurate body temperature.
Thermoscope
It is possible that Francesco Sagredo or Santorio may have added some kind of scales to thermoscopes, and Robert Fludd may have accomplished something similar in 1638. In 1701 Ole Christensen Rømer effectively invented the thermometer by adding a temperature scale (see Rømer scale) to the thermoscope.
Mercury-in-glass thermometer
Celsius used two fixed points in his scale: the temperature of melting ice and the temperature of boiling water. This wasn't a new idea, since Isaac Newton was already working on something similar. The distinction of Celsius was to use the condition of melting and not that of freezing. The experiments for reaching a good calibration of his thermometer lasted for 2 winters. By performing the same experiment over and over again, he discovered that ice always melted at the same calibration mark on the thermometer. He found a similar fixed point in the calibration of boiling water to water vapour (when this is done to high precision, a variation will be seen with atmospheric pressure; Celsius noted this). At the moment that he removed the thermometer from the vapour, the mercury level climbed slightly. This was related to the rapid cooling (and contraction) of the glass.
Xylem Inc.
They continued development in their key area of temperature measurement. They produced the first interchangeable thermistor temperature probes in 1955, and developed it into a complete line of precision interchangeable thermistors in 1961, and in 1965 developed the first linear thermistor temperature sensor, which "Industrial Research" magazine recognized as one of the 100 most significant new technological products of the year. TIn other analytical instruments, they produced the first practical dissolved oxygen meter for field and laboratory use in 1965, which the same magazine recognized as yet another of the most significant technological products of the year.
Miller–Casella thermometer
The Miller–Casella thermometer was a Six's thermometer with a double bulb used extensively by the "Challenger" expedition during the late nineteenth century. The thermomemeter was used for water temperature readings along 360 different research stations around the world's oceans.
Meteorological instrumentation
In 1441, king Sejong's son, Prince Munjong, invented the first standardized rain gauge. These were sent throughout the Joseon Dynasty of Korea as an official tool to assess land taxes based upon a farmer's potential harvest. In 1450, Leone Battista Alberti developed a swinging-plate anemometer, and is known as the first "anemometer". In 1607, Galileo Galilei constructs a thermoscope. In 1643, Evangelista Torricelli invents the mercury barometer. In 1662, Sir Christopher Wren invented the mechanical, self-emptying, tipping bucket rain gauge. In 1714, Gabriel Fahrenheit creates a reliable scale for measuring temperature with a mercury-type thermometer. In 1742, Anders Celsius, a Swedish astronomer, proposed the 'centigrade' temperature scale, the predecessor of the current Celsius scale. In 1783, the first hair hygrometer is demonstrated by Horace-Bénédict de Saussure. In 1806, Francis Beaufort introduced his system for classifying wind speeds. The April 1960 launch of the first successful weather satellite, TIROS-1, marked the beginning of the age where weather information became available globally.
Reversing thermometer
Unlike most conventional mercury thermometers, a reversing thermometer is able to record a given temperature to be viewed at a later time. If the thermometer is flipped upside down, the current temperature will be shown until it is turned upright again. This was the primary device used by oceanographers to determine water temperatures below the surface of the ocean from around 1900 to 1970.
Mercury-in-glass thermometer
Mercury thermometers cover a wide temperature range from ; the instrument's upper temperature range may be extended though the introduction of an inert gas such as nitrogen. This introduction of an inert gas increases the pressure on the liquid mercury and therefore its boiling point is increased, this in combination with replacing the Pyrex glass with fused quartz allows the upper temperature range to be extended to .
List of Dutch inventions and innovations
Various authors have credited the invention of the thermometer to Cornelis Drebbel, Robert Fludd, Galileo Galilei or Santorio Santorio. The thermometer was not a single invention, however, but a development. Though Galileo is often said to be the inventor of the thermometer, what he produced were thermoscopes. The difference between a thermoscope and a thermometer is that the latter has a scale. The first person to put a scale on a thermoscope is variously said to be Francesco Sagredo or Santorio Santorio in about 1611 to 1613.
Irish Famine (1740–41)
Although no barometric or temperature readings for Ireland survive from the Great Frost, a scattered few records survive from Englishmen who made personal readings. The mercury thermometer was invented 25 years earlier by the German pioneer Daniel Gabriel Fahrenheit. Indoor values during January 1740 were as low as . The one outdoor reading that has survived was stated as "thirty-two degrees of frost." This did not include the effects of the wind chill factor, which would have been severe. This kind of weather was "quite outside the Irish experience," notes David Dickson, author of "Arctic Ireland: The Extraordinary Story of the Great Frost and Forgotten Famine of 1740–41".
Medical thermometer
In the 1990s it was decided that mercury-based thermometers were too risky to handle; the vigorous swinging needed to "reset" a mercury maximum thermometer makes it easy to accidentally break it and spill the moderately poisonous mercury. Mercury thermometers have largely been replaced by electronic digital thermometers, or, more rarely, thermometers based on liquids other than mercury (such as galinstan, coloured alcohols and heat-sensitive liquid crystals).
Exergen Corporation
Exergen Corporation, is designer and manufacturer of infrared scanners, thermometers, and sensors headquartered in Watertown, Massachusetts. Exergen products are used in applications including, among others, medical, automotive, food processing, agriculture and textile. The company was founded in 1980 by Francesco Pompei, who patented the world's first temporal artery (forehead) thermometer. Exergen holds more than a dozen patents.
History of the metric system
By the end of the nineteenth century, the fundamental macroscopic laws of thermodynamics had been formulated and although techniques existed to measure temperature using empirical techniques, the scientific understanding of the nature of temperature was minimal.
MMTS (meteorology)
The earliest, and still perhaps most familiar, form is the Maximum minimum thermometer invented by James Six in 1782.
Six's thermometer
The original Six's thermometer design contains mercury, which has been banned for most uses in the European Union and some other parts of the world.
Tasimeter
The tasimeter, or microtasimeter, or "measurer of infinitesimal pressure", is a device designed by Thomas Edison to measure infrared radiation. In 1878, Samuel Langley, Henry Draper, and other American scientists needed a highly sensitive instrument that could be used to measure minute temperature changes in heat emitted from the Sun’s corona during the July 29 solar eclipse, due to occur along the Rocky Mountains. To satisfy those needs Edison devised a "microtasimeter" employing a carbon button.
Wedgwood scale
The Wedgwood scale (°W) is an obsolete temperature scale, which was used to measure temperatures above the boiling point of mercury of . The scale and associated measurement technique were proposed by the English potter Josiah Wedgwood in the 18th century. The measurement was based on the shrinking of clay when heated above red heat, and the shrinking was evaluated by comparing heated and unheated clay cylinders. The scale started at being 0° Wedgwood and had 240 steps of . Both the origin and the step were later found inaccurate.
Thermodynamic temperature
For some types of thermometer the relationship between the property observed (e.g., length of a mercury column) and temperature, is close to linear, so for most purposes a linear scale is sufficient, without point-by-point calibration. For others a calibration curve or equation is required. The mercury thermometer, invented before the thermodynamic temperature was understood, originally "defined" the temperature scale; its linearity made readings correlate well with true temperature, i.e. the "mercury" temperature scale was a close fit to the true scale.
Medical thermometer
In 1868, German physician, pioneer psychiatrist, and medical professor Carl Reinhold August Wunderlich published his studies that consisted of over one million readings from twenty-five thousand patients' temperatures, taken in the underarm. With his findings, he was able to conclude a healthy human's temperature fell within the range of 36.3 to 37.5 °C (97.34 to 99.5 °F).
Galileo thermometer
Although named after the 16th–17th-century physicist Galileo, the thermometer described in this article was not invented by him. Galileo did invent a thermometer, called Galileo's air thermometer (more accurately termed a thermoscope), in or before 1603. The so-called 'Galileo thermometer' was invented by a group of academics and technicians known as the Accademia del Cimento of Florence, who included Galileo's pupil, Torricelli and Torricelli's pupil Viviani. Details of the thermometer were published in the "Saggi di naturali esperienze fatte nell'Academia del Cimento sotto la protezione del Serenissimo Principe Leopoldo di Toscana e descritte dal segretario di essa Accademia" (1666), the Academy's main publication. The English translation of this work (1684) describes the device ('The Fifth Thermometer') as 'slow and lazy', a description that is reflected in an alternative Italian name for the invention, the "termometro lento" (slow thermometer). The outer vessel was filled with 'rectified spirits of wine' (a concentrated solution of ethanol in water); the weights of the glass bubbles were adjusted by grinding a small amount of glass from the sealed end; and a small air space was left at the top of the main vessel to allow 'for the Liquor to rarefie' [i.e. expand].
World's tallest thermometer
It was built in 1991 by the Young Electric Sign Company of Salt Lake City, Utah for Willis Herron, a local Baker businessman who spent $700,000 to build the thermometer next to his Bun Boy restaurant. Its height -- 134 feet -- was in honor of the 134-degree record temperature set in nearby Death Valley on July 10, 1913.
Seconds pendulum
The first (and only) follow-up comparison of the national standards with the international prototype was carried out between 1921 and 1936, and indicated that the definition of the metre was preserved to within 0.2 µm. At this time, it was decided that a more formal definition of the metre was required (the 1889 decision had said merely that the "prototype, at the temperature of melting ice, shall henceforth represent the metric unit of length"), and this was agreed at the 7th CGPM in 1927.
Already in the early days of its existence, the International Committee for Weights and Measures (CIPM) proceeded to define a standard thermometric scale, using the boiling point of water. Since the boiling point varies with the atmospheric pressure, the CIPM needed to define a standard atmospheric pressure. The definition they chose was based on the weight of a column of mercury of 760 mm. But since that weight depends on the local gravity, they now also needed a standard gravity. The 1887 CIPM meeting decided as follows:
Pendulum
The first device to compensate for this error was the mercury pendulum, invented by George Graham in 1721. The liquid metal mercury expands in volume with temperature. In a mercury pendulum, the pendulum's weight (bob) is a container of mercury. With a temperature rise, the pendulum rod gets longer, but the mercury also expands and its surface level rises slightly in the container, moving its centre of mass closer to the pendulum pivot. By using the correct height of mercury in the container these two effects will cancel, leaving the pendulum's centre of mass, and its period, unchanged with temperature. Its main disadvantage was that when the temperature changed, the rod would come to the new temperature quickly but the mass of mercury might take a day or two to reach the new temperature, causing the rate to deviate during that time. To improve thermal accommodation several thin containers were often used, made of metal. Mercury pendulums were the standard used in precision regulator clocks into the 20th century.
Tellurometer
The original tellurometer, known as the Micro-Distancer MRA 1, was introduced in 1957. It was invented by Dr. Trevor Lloyd Wadley of the Telecommunications Research Laboratory of the South African Council for Scientific and Industrial Research (CSIR), also responsible for the Wadley Loop receiver, which allowed precision tuning over wide bands, a task that had previously required switching out multiple crystals.
Six's thermometer
In the bend of the U is a section of mercury, a metal which is liquid at normal temperatures. This is pushed around the tube by the thermal expansion and contraction of the alcohol in the first bulb as it responds to the external temperature. The vacuum in other bulb allows free movement of the alcohol and mercury. It is the alcohol which measures the temperature; the mercury indicates the temperature reading on both scales. This is unlike a normal mercury thermometer, in which the expansion and contraction of mercury itself indicates temperature.
Observer effect (physics)
In thermodynamics, a standard mercury-in-glass thermometer must absorb or give up some thermal energy to record a temperature, and therefore changes the temperature of the body which it is measuring.
Mercury-in-glass thermometer
The typical "fever thermometer" contains between of elemental mercury. Swallowing this amount of mercury would, it is said, pose little danger but the inhaling of the vapour could lead to health problems.
Hygrometer
A hygrometer () is an instrument used to measure the amount of humidity and water vapor in the atmosphere, in soil, or in confined spaces. Humidity measurement instruments usually rely on measurements of some other quantity such as temperature, pressure, mass, a mechanical or electrical change in a substance as moisture is absorbed. By calibration and calculation, these measured quantities can lead to a measurement of humidity. Modern electronic devices use temperature of condensation (called the dew point), or changes in electrical capacitance or resistance to measure humidity differences. The first crude hygrometer was invented by the Italian Renaissance polymath Leonardo da Vinci in 1480 and a more modern version was created by Swiss polymath Johann Heinrich Lambert in 1755.
Temperature
Empirically based temperature scales rely directly on measurements of simple physical properties of materials. For example, the length of a column of mercury, confined in a glass-walled capillary tube, is dependent largely on temperature, and is the basis of the very useful mercury-in-glass thermometer. Such scales are valid only within convenient ranges of temperature. For example, above the boiling point of mercury, a mercury-in-glass thermometer is impracticable. Most materials expand with temperature increase, but some materials, such as water, contract with temperature increase over some specific range, and then they are hardly useful as thermometric materials. A material is of no use as a thermometer near one of its phase-change temperatures, for example its boiling-point.
Jean-André Deluc
He devised a portable barometer for use in geological expeditions. His "Recherches sur les modifications de l'atmosphère" (2 vols. 4to, Geneva, 1772; 2nd ed., 4 vols. Paris, 1784) contain experiments on moisture, evaporation and the indications of hygrometers and thermometers. He applied the barometer to the determination of heights. The "Philosophical Transactions" published his account of a new hygrometer, which resembled a mercurial thermometer, with an ivory bulb, which expanded by moisture, and caused the mercury to descend. He later devised a whalebone hygrometer which sparked a bitter controversy with Horace-Bénédict de Saussure, himself inventor of a hair hygrometer. He gave the first correct rules for measuring heights with the help of a barometer. Deluc advocated the use of mercury, instead of alcohol, in thermometers.
James Six
James Six FRS (1731 – 25 August 1793) was a British scientist born in Canterbury. He is noted for his invention, in 1780, of Six's thermometer, commonly known as the maximum minimum thermometer. This device is still in common use today and widely sold in garden centres.
Mercury-in-glass thermometer
Anders Celsius, a Swedish scientist, devised the Celsius scale, which was described in his publication "The origin of the Celsius temperature scale" in 1742.
Fahrenheit hydrometer
The Fahrenheit hydrometer is a device used to measure the density of a liquid. It was invented by Daniel Gabriel Fahrenheit (1686–1736), better known for his work in thermometry.
Nansen bottle
The sea temperature at the water sampling depth is recorded by means of a reversing thermometer fixed to the Nansen bottle. This is a mercury thermometer with a constriction in its capillary tube which, when the thermometer is inverted, causes the thread to break and trap the mercury, fixing the temperature reading. Since water pressure at depth will compress the thermometer walls and affect the indicated temperature, the thermometer is protected by a rigid enclosure. A non-protected thermometer is paired with the protected one, and comparison of the two temperature readings allows both temperature and pressure at the sampling point to be determined.
Mercury-in-glass thermometer
The application of mercury (1714) and Fahrenheit scale (1724) for liquid-in-glass thermometers ushered in a new era of accuracy and precision in thermometry, and is still to this day regarded as one of the most accurate thermometers available.
Millimeter of mercury
Mercury manometers were the first accurate pressure gauges; they are less used today due to mercury's toxicity, the mercury column's sensitivity to temperature and local gravity, and the greater convenience of other instrumentation. They displayed the pressure difference between two fluids as a vertical difference between the mercury levels in two connected reservoirs.
Marie Curie
She used an innovative technique to investigate samples. Fifteen years earlier, her husband and his brother had developed a version of the electrometer, a sensitive device for measuring electric charge. Using her husband's electrometer, she discovered that uranium rays caused the air around a sample to conduct electricity. Using this technique, her first result was the finding that the activity of the uranium compounds depended only on the quantity of uranium present. She hypothesized that the radiation was not the outcome of some interaction of molecules but must come from the atom itself. This hypothesis was an important step in disproving the assumption that atoms were indivisible.
List of Dutch inventions and innovations
Various authors have credited the invention of the thermometer to Cornelis Drebbel, Robert Fludd, Galileo Galilei or Santorio Santorio. The thermometer was not a single invention, however, but a development. However, each inventor and each thermometer was unique – there was no standard scale. In 1665 Christiaan Huygens suggested using the melting and boiling points of water as standards. The Fahrenheit scale is now usually defined by two fixed points: the temperature at which water freezes into ice is defined as 32 degrees Fahrenheit (°F), and the boiling point of water is defined to be 212 °F, a 180 degree separation, as defined at sea level and standard atmospheric pressure. In 1742, Swedish astronomer Anders Celsius created a temperature scale which was the reverse of the scale now known by the name "Celsius": "0" represented the boiling point of water, while "100" represented the freezing point of water. From 1744 until 1954, 0 °C was defined as the freezing point of water and 100 °C was defined as the boiling point of water, both at a pressure of one standard atmosphere with mercury being the working material.
Medical thermometer
Prominent Dutch mathematician, astronomer and physicist Christiaan Huygens created a clinical thermometer in 1665, to which he added an early form of the centigrade scale by setting the scale to the freezing and boiling points of water. By 1742 Swedish astronomer Anders Celsius created the Celsius temperature scale that was the reverse of the modern scale, in that "0" was the boiling point of water, while "100" was freezing. It would later be reversed by Swedish botanist Carolus Linnaeus (1707–1778) in 1744.
Leslie cube
Leslie's cube is a device used in the measurement or demonstration of the variations in thermal radiation emitted from different surfaces at the same temperature. It was devised in 1804 by John Leslie (1766–1832), a Scottish mathematician and physicist. In the version of the experiment described by John Tyndall in the late 1800s, one of the cube's vertical sides is coated with a layer of gold, another with a layer of silver, a third with a layer of copper, while the fourth side is coated with a varnish of isinglass. The cube is made from a solid block of metal with a central cavity. In use, the cavity was filled with hot water; the entire cube has essentially the same temperature as the water. The thermal detector (on the far right in the figure) showed much greater emission from the side with varnish than from any of the other three sides.
Wilbur Olin Atwater
With annual costs exceeding $10 thousand, the respiration calorimeter was considered a dream project for the 19th century. Atwater began the first of about 500 experiments in 1896. In fact, "he made history by establishing America’s first state agricultural experiment station at [Wesleyan]." He studied respiration and metabolism in animals and in humans. The calorimeter aided studies in food analysis, dietary evolution, work energy consumption, and digestible foods. It measured the human metabolism balance by analyzing the heat produced and metabolic rate by a person performing certain physical activities. With this machine, the dynamics of metabolism could be quantified and the balance between food intake and energy output could be measured. Atwater applied the first law of thermodynamics to his research: Energy can be transformed (i.e., changed from one form to another), but it can neither be created nor destroyed. Before Atwater's development of the respiration calorimeter, many experiments on calorie intake and expenditure had been conducted on animals. During this period, there was a widely held belief that the first law of thermodynamics applied to animals, but did not apply to humans because they were unique. Atwater demonstrated that whatever amount of consumed energy humans cannot use is left over and stored in the body. His findings thus established that the first law applied to humans as well as animals. Atwater's research and conclusions in this regard changed both how people thought about science and about humans.
Wilhelm Lambrecht
In 1867, when he came back from the world exhibition in Paris and brought the first chromic acid cell with him, he also met the astronomer Wilhelm Klinkerfues. Klinkerfues had developed a bifilar-hygrometer which was widely used but did not prove in laymen's hands. After that Lambrecht built a hair hygrometer, "Model Klinkerfues". In 1873, after separation from Klinkerfues, Lambrecht started to build new meteorological instruments such as polymeters, dew point monitors, and aspiration psychrometers. His weather telegraphs, weather columns and combinations of different meteorological instruments were in use at several bigger cities and foreign health resorts before World War I. Lambrecht also built medical thermometers. At the same time he developed the so-called minimum thermometer with a narrowing of the lumen of the capillary which is placed above the mercury container. His precision instruments are well-known all over the world.
Peter Orris
Orris was an attendee of every negotiating session of a global treaty to eliminate mercury from thermometers globally, which has resulted in the phasing out of mercury based thermometers by 2020.
Thermophysics
This field of observations and computer modeling was first applied to Mars due to the ideal atmospheric pressure for characterizing granular materials based upon temperature [Wechsler and Glaser, 1965]. The Mariner 6, Mariner 7, and Mariner 9 spacecraft carried thermal infrared radiometers [Neugebauer, et al., 1971; Kieffer et al., 1973], and a global map of thermal inertia was produced from modeled surface temperatures [Kieffer, et al., 1977] collected by the Infrared Thermal Mapper Instruments (IRTM) on board the Viking 1 and 2 Orbiters.
Pendulum
During the 18th and 19th century, the pendulum clock's role as the most accurate timekeeper motivated much practical research into improving pendulums. It was found that a major source of error was that the pendulum rod expanded and contracted with changes in ambient temperature, changing the period of swing. This was solved with the invention of temperature compensated pendulums, the mercury pendulum in 1721 and the gridiron pendulum in 1726, reducing errors in precision pendulum clocks to a few seconds per week.
Jean Nicolas Fortin
Jean Nicolas Fortin (1750–1831) was a French maker of scientific instruments, born august the 9th 1750in Mouchy-la-Ville in Picardy. Among his customers were such noted scientists as Lavoisier, for whom he made a precision balance, Gay-Lussac, François Arago and Pierre Dulong.
Fortin is chiefly remembered for his design of barometer, now called a "Fortin barometer", which he introduced in about 1800. In this, the mercury cistern has a glass portion through which the mercury exposed to the atmosphere can be seen, and an ivory needle which was made just to touch its mirror image in the mercury before the reading was taken. This allows for the fact that, when the mercury column in the closed tube falls, the level in the cistern rises, and the difference in height between the two cannot be accurately determined unless the height of the latter is taken into account.
Pierre Curie
Prior to his famous doctoral studies on magnetism, he designed and perfected an extremely sensitive torsion balance for measuring magnetic coefficients. Variations on this equipment were commonly used by future workers in that area. Pierre Curie studied ferromagnetism, paramagnetism, and diamagnetism for his doctoral thesis, and discovered the effect of temperature on paramagnetism which is now known as Curie's law. The material constant in Curie's law is known as the Curie constant. He also discovered that ferromagnetic substances exhibited a critical temperature transition, above which the substances lost their ferromagnetic behavior. This is now known as the Curie temperature. The Curie temperature is used to study plate tectonics, treat hypothermia, measure caffeine, and to understand extraterrestrial magnetic fields.
Hermann Fol
Fol is credited with the invention of the barthometer. The barometer properly measured mercury, the pressure to which the apparatus had been submitted, and the determination of the depth of compressible liquid within the device. His invention consisted of a spherical glass reservoir of a liquid that is slightly compressible, such as water or ether. The single hole to the vessel is a capillary tube that corresponds with a minor reservoir filled with mercury. Mercury, along the assumed temperature of the water at the sea bottom, must remain at the stage with the hole in the pointed stopper within the large reservoir. The top surface of the mercury is released to contact the water. The device is lowered by the sound line. The water or ether will compress as the device lowers, a given amount of each atmosphere of pressure, and a correlating amount of mercury will release between the hole and lower to the base of the bottom reservoir.
Moritz Immisch
In 1881 Immisch obtained a patent for a remarkably small watch-shaped thermometer, functioning on the variable expansive properties of fluid in a Bourdon tube. This metallic instrument was designed to be more robust than contemporary glass thermometers filled with mercury - for this reason it was first branded as an 'avitreous', or metallic thermometer. The speed of the temperature-expansion and the calibration of the watch-dial indicator allowed very accurate readings to be taken, and its small size made it highly portable as a clinical instrument.
Thermistor
The power dissipated in a thermistor is typically maintained at a very low level to ensure insignificant temperature measurement error due to self heating. However, some thermistor applications depend upon significant "self heating" to raise the body temperature of the thermistor well above the ambient temperature so the sensor then detects even subtle changes in the thermal conductivity of the environment. Some of these applications include liquid level detection, liquid flow measurement and air flow measurement.
The first NTC thermistor was discovered in 1833 by Michael Faraday, who reported on the semiconducting behavior of silver sulfide. Faraday noticed that the resistance of silver sulfide decreased dramatically as temperature increased. (This was also the first documented observation of a semiconducting material.)
History of perpetual motion machines
In the 1760s, James Cox and John Joseph Merlin developed Cox's timepiece. Cox claimed that the timepiece was a true perpetual motion machine, but as the device is powered by changes in atmospheric pressure via a mercury barometer, this is not the case.
Rømer scale
The Rømer scale is no longer in use but is of some historical importance. Alongside the Newton scale, it was the first "calibrated" scale. Previous thermometers gave only an indication of whether the temperature was rising or falling, or else were highly inaccurate. For instance the top and bottom marks of thermometers were typically set to the hottest and coldest days, respectively, of the current year which clearly would vary from year to year. The idea of using two fiduciary points with equally spaced calibration marks between them was completely new.
Merle Randall
Merle Randall (January 29, 1888 – March 17, 1950) was an American physical chemist famous for his work with Gilbert N. Lewis, over a period of 25 years, in measuring reaction heat of chemical compounds and determining their corresponding free energy. Together, their 1923 textbook ""Thermodynamics and the Free Energy of Chemical Substances"" became a classic work in the field of chemical thermodynamics.
Mercury-in-glass thermometer
To measure lower meteorological temperatures, a thermometer containing a mercury-thallium alloy which does not solidify until the temperature drops to may be used.
Six's thermometer
In 2006, S.Brannan & Sons Ltd, a UK company, was granted a patent for a mercury-free version of Six's maximum–minimum thermometer: instead of mercury two immiscible liquids are used supporting an index. The thermometer operates in the same way as the mercury version.
Medical thermometer
The medical thermometer began as an instrument more appropriately called a water thermoscope, constructed by Galileo Galilei circa 1592–1593. It lacked an accurate scale with which to measure temperature and could be affected by changes in atmospheric pressure.
Thermometer
The above instruments suffered from the disadvantage that they were also barometers, i.e. sensitive to air pressure. In 1629, Joseph Solomon Delmedigo, a student of Galileo, published what is apparently the first description and illustration of a sealed liquid-in-glass thermometer. It is described as having a bulb at the bottom of a sealed tube partially filled with brandy. The tube has a numbered scale. Delmedigo does not claim to have invented this instrument, nor does he name anyone else as its inventor. In about 1654 Ferdinando II de' Medici, Grand Duke of Tuscany (1610–1670), actually produced such an instrument, the first modern-style thermometer, dependent on the expansion of a liquid, and independent of air pressure. Many other scientists experimented with various liquids and designs of thermometer.
Galileo Galilei
In about 1593, Galileo constructed a thermometer, using the expansion and contraction of air in a bulb to move water in an attached tube.
Squarewave voltammetry
When first reported by Barker in 1957, the working electrode utilized was primarily a dropping mercury electrode (DME). When using a DME, the surface area of the mercury drop is constantly changing throughout the course of the experiment; for this reason, complex mathematical modeling was at times required in order to analyze collected electrochemical data. The squarewave voltammetric technique allowed for the collection of the desired electrochemical data within one mercury drop, meaning that the need for mathematical modeling to account for the changing working electrode surface area was no longer needed. In short, the introduction and development of this technique allowed for the rapid collection of reliable and easily reproducible electrochemical data using DME or SDME working electrodes. With continued improvements from many electrochemists (particularly the Osteryoungs), SWV is now one of the primary voltammetric techniques available on modern potentiostats.
Torr
Torricelli attracted considerable attention when he demonstrated the first mercury barometer to the general public. He is credited with giving the first modern explanation of atmospheric pressure. Scientists at the time were familiar with small fluctuations in height that occurred in barometers. When these fluctuations were explained as a manifestation of changes in atmospheric pressure, the science of meteorology was born.
Challenger expedition
The primary thermometer used throughout the "Challenger" expedition was the Miller–Casella thermometer, which contained two markers within a curved mercury tube to record the maximum and minimum temperature through which the instrument traveled. Several of these thermometers would be lowered at various depths for recording. However, this design assumed that the water closer to the surface of the ocean was always warmer than that below. During the voyage, "Challenger"s crew tested the reversing thermometer, which could measure temperature at specified depths. Afterwards, this type of thermometer was used extensively until the second half of the 20th century.
Mercury (element)
Most thermometers now use pigmented alcohol instead of mercury, and galinstan alloy thermometers are also an option. Mercury thermometers are still occasionally used in the medical field because they are more accurate than alcohol thermometers, though both are commonly being replaced by electronic thermometers and less commonly by galinstan thermometers. Mercury thermometers are still widely used for certain scientific applications because of their greater accuracy and working range.
Richard Towneley
During the winter of 1664–5, the skies of the northern hemisphere were dominated by a brilliant comet, which was the most conspicuous since that of 1618. When Hooke made his first observations of the comet of 1664, he devised his own method of computing the angular diameter of the nucleus by comparing it with the apparent diameter of a weather vane support on distant building and measuring the distance between the telescope and the weather vane. Accurate angular measurements were of great importance to the astronomers of the time and Hooke realised he needed a precise instrument for this purpose. His problem was solved in 1667, when he saw Richard Towneley's micrometer, which was based on a prototype of 1640 invented by William Gascoigne. This instrument used a pair of fine-pitched screws to move two pointers in the focal plane of a Keplerian telescope. By enclosing the object to be measured between the pointers, its angular diameter could be computed to within a few arc seconds, providing the observer knew the exact focal length of the telescope and the pitch of the screw which moved the pointers. Hooke published an engraving of the instrument to accompany Towneley's description in 1667. Its principle was to lie at the heart of astronomical measurement down to the twentieth century.
History of thermodynamics
More quantitative studies by James Prescott Joule in 1843 onwards provided soundly reproducible phenomena, and helped to place the subject of thermodynamics on a solid footing. William Thomson, for example, was still trying to explain Joule's observations within a caloric framework as late as 1850. The utility and explanatory power of kinetic theory, however, soon started to displace caloric and it was largely obsolete by the end of the 19th century. Joseph Black and Lavoisier made important contributions in the precise measurement of heat changes using the calorimeter, a subject which became known as thermochemistry.Irish physicist and chemist Robert Boyle in 1656, in coordination with English scientist Robert Hooke, built an air pump. Using this pump, Boyle and Hooke noticed the pressure-volume correlation: P.V=constant. In that time, air was assumed to be a system of motionless particles, and not interpreted as a system of moving molecules. The concept of thermal motion came two centuries later. Therefore, Boyle's publication in 1660 speaks about a mechanical concept: the air spring. Later, after the invention of the thermometer, the property temperature could be quantified. This tool gave Gay-Lussac the opportunity to derive his law, which led shortly later to the ideal gas law. But, already before the establishment of the ideal gas law, an associate of Boyle's named Denis Papin built in 1679 a bone digester, which is a closed vessel with a tightly fitting lid that confines steam until a high pressure is generated.
Medical thermometer
Mercury-in-glass thermometers have been considered the most accurate liquid-filled types. However, mercury is a toxic heavy metal, and mercury has only been used in clinical thermometers if protected from breakage of the tube.
Voltammetry
The 1960s and 1970s saw many advances in the theory, instrumentation, and the introduction of computer added and controlled systems. Modern polarographic and voltammetric methods on mercury electrodes came about in three sections. 
The first section includes the development of the mercury electrodes. The following electrodes were produced: dropping mercury electrode, mercury steaming electrode, hanging mercury drop electrode, static mercury drop electrode, mercury film electrode, mercury amalgam electrodes, mercury microelectrodes, chemically modified mercury electrodes, controlled growth mercury electrodes, and contractible mercury drop electrodes.
Thermostat
Early technologies included mercury thermometers with electrodes inserted directly through the glass, so that when a certain (fixed) temperature was reached the contacts would be closed by the mercury. These were accurate to within a degree of temperature.
History of the metric system
In a paper published in 1843, James Prescott Joule first demonstrated a means of measuring the energy transferred between different systems when work is done thereby relating Nicolas Clément's calorie, defined in 1824 as "the amount of heat required to raise the temperature of 1 kg of water from 0 to 1 °C at 1 atmosphere of pressure" to mechanical work. Energy became the unifying concept of nineteenth century science, initially by bringing thermodynamics and mechanics together and later adding electrical technology.
Mercury-in-glass thermometer
Since European Union directive 2007/51/EC came into force on 3 April 2009, the UK Health Protection Agency (HPA) reported that mercury thermometers could no longer be sold to the general public. Shops holding stocks of unsold thermometers had to withdraw them from sale; mercury thermometers purchased before this date could be used without legal implications. The purpose of these restrictions is to protect the environment and public health by decreasing the amount of mercury waste released. The HPA had, in 2007, released a guide to dealing with small spills of mercury.
Temperature measurement
Many methods have been developed for measuring temperature. Most of these rely on measuring some physical property of a working material that varies with temperature. One of the most common devices for measuring temperature is the glass thermometer. This consists of a glass tube filled with mercury or some other liquid, which acts as the working fluid. Temperature increase causes the fluid to expand, so the temperature can be determined by measuring the volume of the fluid. Such thermometers are usually calibrated so that one can read the temperature simply by observing the level of the fluid in the thermometer. Another type of thermometer that is not really used much in practice, but is important from a theoretical standpoint, is the gas thermometer.
Other important devices for measuring temperature include:
Michelangelo Ricci
He played a significant part in the theoretical debates and experiments that led up to Torricelli's discovery of atmospheric pressure and invention of the mercury barometer. In particular he followed the experiments in this field by Gasparo Berti, in Rome.
Mercury beating heart
The mercury beating heart was first observed by Carl Adolf Paalzow in 1858. Jöns Jakob Berzelius is reported to have used electrodes.
Réaumur scale
Réaumur’s thermometer contained diluted alcohol (ethanol) and was constructed on the principle of using 0° for the freezing temperature of water, and graduating the tube into degrees, each of which was one-thousandth of the volume contained by the bulb and tube up to the zero mark. He suggested that the concentration of alcohol employed be such that it began boiling at 80 °Ré — that is, when it had expanded in volume by 8%. He chose alcohol instead of mercury because it expands more visibly, but this posed problems: his original thermometers were very bulky, and the low boiling point of alcohol made them unsuitable for many applications. Instrument-makers generally chose different liquids, and then used 80 °Ré to signify the boiling point of water, causing much confusion. During 1772 Jean-André Deluc studied the several substances then used in thermometers and concluded that mercurial thermometers were the best for practical use; for example, if two equal amounts of water at "x" and "y" degrees were mixed, the temperature of the result was then the average of "x" and "y" degrees, and this relationship was only reliable when mercury was used. From the late 18th century mercury was used almost without exception.
Clifford Allbutt
In 1870 Allbutt published "Medical Thermometry", an article outlining the history of thermometry and describing his invention: a clinical thermometer approximately 6 inches in length that a physician could have habitually in a pocket. His version of the thermometer, devised in 1867, was quickly adopted elsewhere, instead of the model previously in use, which was one foot long and which patients were required to hold for about twenty minutes.
Calorimeter
In 1761 Joseph Black introduced the idea of latent heat which lead to creation of the first ice-calorimeters. In 1780, Antoine Lavoisier used the heat from the guinea pig's respiration to melt snow surrounding his apparatus, showing that respiratory gas exchange is combustion, similar to a candle burning. Lavoisier dubbed this apparatus the calorimeter, based on both Greek and Latin roots. One of the first ice calorimeters was used in the winter of 1782 by Lavoisier and Pierre-Simon Laplace, which relied on the heat required to melt ice to water to measure the heat released from chemical reactions.
Thomas Hutchins (naturalist)
He performed preliminary experiments on the congelation (freezing point) of mercury in 1775, identifying the problem with previous attempts as being due to the abrupt change of volume of the mercury in the thermometer as it changed state. Apparatus for an improved method was devised and after a series of careful experiments 1779–1782, its freezing point was determined at −39 °F.
For this work, highly praised by Cavendish, he was awarded the Royal Society's Copley Medal in 1783, jointly with John Goodricke (for unrelated work).
Medical thermometer
Some electronic thermometers may work by contact (the electronic sensor is placed in the location where temperature is to be measured, and left long enough to reach equilibrium). These typically reach equilibrium faster than mercury thermometers; the thermometer may beep when equilibrium has been reached, or the time may be specified in the manufacturer's documentation.
Telemeter
Many authors place the beginning of telemeters (in the general sense) in the steam age, although they were not called such at the time. Examples of these are James Watt's (1736-1819) additions to his steam engines of the mercury pressure gauge and the fly-ball governor.
History of geophysics
The thermoscope, or Galileo thermometer, was constructed by Galileo Galilei in 1607. In 1643, Evangelista Torricelli invented the mercury barometer. Blaise Pascal (in 1648) rediscovered that atmospheric pressure decreases with height, and deduced that there is a vacuum above the atmosphere.
Warren S. Johnson
Johnson had an inquisitive mind and was particularly interested in electricity. In 1883, he developed a thermostat, which he deployed at the State Normal School. He called the instrument an "electric tele-thermoscope" in the patent application. It was a bi-metal coiled thermostat with a mercury switch, which could be used to ring a bell to alert the fireman to open or close the heating damper. While not the first bi-metal thermostat, Johnson received a patent for the device and interested William Plankinton, heir to the Plankinton Packing Company, to provide financial backing to manufacture the device. 
The Johnson Electric Service Company was established in 1885 in Milwaukee, Wisconsin. Johnson’s most notable contribution to temperature control was the automatic multi-zone temperature control system – a pneumatic system that used a bi-metal thermostat to control air flow through a nozzle and thereby operate a pilot regulator. The amplified air signal from the regulator was then used to control a steam or hot water valve on a heat exchanger, or to control a damper of a forced air system. He received a patent for the system in 1895.
Ole Rømer
Rømer also invented the modern thermometer showing the temperature between two fixed points, namely the points at which water respectively boils and freezes.
Moritz Immisch
Its small size made the device very popular and it was referred to in many medical journals throughout the 1880s both in England and in the US. Immisch himself later wrote an article comparing the merits of his thermometer with others then in use for the New York Medical Journal in 1889.
René Antoine Ferchault de Réaumur
He was noted for a thermometer he constructed on the principle of taking the freezing point of water as 0°, and graduating the tube into degrees each of which was one-thousandth of the volume contained by the bulb and tube up to the zero mark. It was an accident dependent on the particular alcohol employed which made the boiling-point of water 80°; mercurial thermometers graduated into 80 equal parts between the freezing- and boiling-points of water are named Réaumur thermometers but diverge from his design and intention.
Evangelista Torricelli
Torricelli's chief invention was the mercury barometer. "This instrument is named from two Greek words, signifying two measures of weight, since by it a column of air is weighed against a column of mercury." The barometer arose from the need to solve a practical problem. Pump makers of the Grand Duchy of Tuscany attempted to raise water to a height of 12 meters or more, but found that 10 meters was the limit with a suction pump (as recounted in Galileo's Dialogue). Torricelli employed mercury, thirteen times more dense than water. In 1643 he created a tube approximately one meter long, sealed at the top, filled it with mercury, and set it vertically into a basin of mercury. The column of mercury fell to about 76 cm, leaving a Torricellian vacuum above. As we now know, the column's height fluctuated with changing atmospheric pressure; this was the first barometer. The discovery of the principle of the barometer has perpetuated his fame ("Torricellian tube", "Torricellian vacuum"). The torr, a unit of pressure used in vacuum measurements, is named after him. "12 years before Torricelli's observations, Descartes, the French philosopher, had made the same observation, although he does not appear to have turned it to any account."
Medical thermometer
Italian physician Santorio Santorio is the first known individual to have put a measurable scale on the thermoscope and wrote of it in 1625, though he possibly invented one as early as 1612. His models were bulky, impractical and took a fair amount of time to take an accurate oral reading of the patient's temperature.
Calibration
One of the earliest pressure measurement devices was the Mercury barometer, credited to Torricelli (1643), which read atmospheric pressure using Mercury. Soon after, water-filled manometers were designed. All these would have linear calibrations using gravimetric principles, where the difference in levels was proportional to pressure. The normal units of measure would be the convenient inches of mercury or water.
Meteorology
In 1441, King Sejong's son, Prince Munjong of Korea, invented the first standardized rain gauge. These were sent throughout the Joseon Dynasty of Korea as an official tool to assess land taxes based upon a farmer's potential harvest. In 1450, Leone Battista Alberti developed a swinging-plate anemometer, and was known as the first "anemometer". In 1607, Galileo Galilei constructed a thermoscope. In 1611, Johannes Kepler wrote the first scientific treatise on snow crystals: "Strena Seu de Nive Sexangula (A New Year's Gift of Hexagonal Snow)". In 1643, Evangelista Torricelli invented the mercury barometer. In 1662, Sir Christopher Wren invented the mechanical, self-emptying, tipping bucket rain gauge. In 1714, Gabriel Fahrenheit created a reliable scale for measuring temperature with a mercury-type thermometer. In 1742, Anders Celsius, a Swedish astronomer, proposed the "centigrade" temperature scale, the predecessor of the current Celsius scale. In 1783, the first hair hygrometer was demonstrated by Horace-Bénédict de Saussure. In 1802–1803, Luke Howard wrote "On the Modification of Clouds", in which he assigns cloud types Latin names. In 1806, Francis Beaufort introduced his system for classifying wind speeds. Near the end of the 19th century the first cloud atlases were published, including the "International Cloud Atlas", which has remained in print ever since. The April 1960 launch of the first successful weather satellite, TIROS-1, marked the beginning of the age where weather information became available globally.
Mercury (element)
Mercury is used in thermometers, barometers, manometers, sphygmomanometers, float valves, mercury switches, mercury relays, fluorescent lamps and other devices, though concerns about the element's toxicity have led to mercury thermometers and sphygmomanometers being largely phased out in clinical environments in favor of alternatives such as alcohol- or galinstan-filled glass thermometers and thermistor- or infrared-based electronic instruments. Likewise, mechanical pressure gauges and electronic strain gauge sensors have replaced mercury sphygmomanometers.
Gdańsk University of Technology
Daniel Gabriel Fahrenheit (1686-1736) was born in Gdańsk. He is mainly known for being the first to use mercury in temperature measuring devices (previously alcohol was used) and developed his own scale of 0 to 212 degrees.
Thermometer
Such a mechanism was later used to show the hotness and coldness of the air with a tube in which the water level is controlled by the expansion and contraction of the gas. These devices were developed by several European scientists in the 16th and 17th centuries, notably Galileo Galilei. As a result, devices were shown to produce this effect reliably, and the term "thermoscope" was adopted because it reflected the changes in sensible heat (the concept of temperature was yet to arise). The difference between a thermoscope and a thermometer is that the latter has a scale. Though Galileo is often said to be the inventor of the thermometer, what he produced were thermoscopes.
Cornelis Drebbel
Drebbel invented a chicken incubator and a mercury thermostat which automatically kept it stable at a constant temperature; one of the first recorded feedback-controlled devices. He also developed and demonstrated a working air conditioning system. The invention of a working thermometer is also credited to Drebbel.
Benjamin Franklin
Franklin noted a principle of refrigeration by observing that on a very hot day, he stayed cooler in a wet shirt in a breeze than he did in a dry one. To understand this phenomenon more clearly Franklin conducted experiments. In 1758 on a warm day in Cambridge, England, Franklin and fellow scientist John Hadley experimented by continually wetting the ball of a mercury thermometer with ether and using bellows to evaporate the ether. With each subsequent evaporation, the thermometer read a lower temperature, eventually reaching . Another thermometer showed that the room temperature was constant at . In his letter "Cooling by Evaporation", Franklin noted that, "One may see the possibility of freezing a man to death on a warm summer's day."
Mercury-in-glass thermometer
Finally, Celsius proposed a method of calibrating a thermometer:These points are adequate for approximate calibration but both vary with atmospheric pressure. Nowadays, the triple point of water is used instead of the freezing point (the triple point occurs at 273.16 kelvins (K), 0.01 °C).
Telemeter
By the late 19th century the term had been thoroughly hijacked by electrical engineers applying it to electrically operated devices measuring many other quantities besides distance. These included such sensors as the thermocouple (from the work of Thomas Johann Seebeck), the resistance thermometer (by William Siemens based on the work of Humphry Davy), and the electrical strain gauge (based on Lord Kelvin's discovery that conductors under mechanical strain change their resistance) and output devices such as Samuel Morse's telegraph sounder and the relay. In 1889 this led the Institution of Civil Engineers to suggest that the term for a rangefinder be replaced with tachometer. In the 1930s use of electrical telemeters grew rapidly. The electrical strain gauge was widely used in rocket and aviation research and the radiosonde was invented for meteorological measurements. The advent of World War II gave an impetus to industrial development and henceforth many of these telemeters became commercially viable.
Siemens mercury unit
The Siemens mercury unit is an obsolete unit of electrical resistance. It was defined by Werner von Siemens in 1860 as the resistance of a mercury column with a length of one metre and uniform cross-section of held at a temperature of zero degrees Celsius. It is equivalent to approximately 0.953 ohm.
Dolorimeter
In 1940, James D. Hardy, Harold G. Wolff and Helen Goodell of Cornell University introduced the first dolorimeter as a method for evaluating the effectiveness of analgesic medications. They did their work at New York Hospital. They focused the light of a 100 watt projection lamp with a lens on an area of skin that had been blackened. They found that most people expressed a pain sensation when the skin temperature reached 113 °F (45 °C). They also found that after the skin temperature reached 152 °F (67 °C), the pain sensations did not intensify even if the heat was increased. They developed a pain scale, called the "Hardy-Wolff-Goodell" scale, with 10 gradations, or 10 levels. They assigned the name of "dols" to these levels. Unfortunately, other researchers were not able to reproduce the results of Hardy, Wolff and Goodell, and the device and the approach were abandoned. Harvard Medical School Professor and Massachusetts General Hospital Anaesthetist Henry K. Beecher (1957) expressed skepticism about this method of measuring pain.