Barometer invented by Evangelista Torricelli in year 1643 Invented by : Evangelista Torricelli Invented in year : 1643 A Barometer is an instrument used to measure atmospheric pressure. It can measure the pressure exerted by the atmosphere by using water, air, or mercury. There are two common types of Barometer, these are the Aneroid Barometer And the Mercurial Barometer which was invented first. The classic Mercury Barometer is typically a glass tube about 3 feet high with one end open and the other end sealed. The tube is filled with mercury. This glass tube sits upside down in a container, called the reservoir, which also contains mercury. The mercury level in the glass tube falls, creating a vacuum at the top. Pressure tendency can forecast short term changes in the weather. The barometer works by balancing the weight of mercury in the glass tube against the atmospheric pressure just like a set of scales. If the weight of mercury is less than the atmospheric pressure, the mercury level in the glass tube rises. If the weight of mercury is more than the atmospheric pressure, the mercury level falls.

Atmospheric pressure is basically the weight of air in the atmosphere above the reservoir, so the level of mercury continues to change until the weight of mercury in the glass tube is exactly equal to the weight of air above the reservoir. In areas of low pressure, air is rising away from the surface of the earth more quickly than it can be replaced by air flowing in from surrounding areas. This reduces the weight of air above the reservoir so the mercury level drops to a lower level. In contrast, in areas of high pressure, air is sinking toward the surface of the earth more quickly than it can flow out to surrounding areas. There is more air above the reservoir, so the weight of air is higher and the mercury rises to a higher level to balance things out. Numerous measurements of air pressure are used within surface weather analysis to help find surface troughs, high pressure systems, and frontal boundaries. The Invention Evangelista Torricelli invented the first barometer. It was also known as the Torricelli's Tube. He was born October 15, 1608, in Faenza, Italy. He was a physicist and mathematician. It was Galileo that suggested Evangelista Torricelli use mercury in his vacuum experiments.

Torricelli filled a four-foot long glass tube with mercury and inverted the tube into a dish. Some of the mercury did not escape from the tube and Torricelli observed the vacuum that was created. He became the first scientist to create a sustained vacuum and to discover the principle of a barometer. Torricelli realized that the variation of the height of the mercury from day to day was caused by changes in the atmospheric pressure. Torricelli built the first mercury barometer around 1644. Pump makers of the Grand Duke of Tuscany attempted to raise water to a height of forty feet or more, but found that thirty-two feet was the limit to which it would rise in the suction pump. Strange enough, Galileo, who knew all about the weight of the air, had recourse to the old theory that Nature Abhors a Vacuum, modifying the law by stating that the horror extended only to about thirty-two feet. Torricelli at once conceived the correct explanation. He tried the experiment with quicksilver, a liquid fourteen times as heavy as water, expecting the column which would counterbalance the air to be proportionally smaller.

He filled a tube three feet long, and hermetically closed at one end, with mercury and set it vertically with the open end in a basin of mercury, taking care that no air-bubbles should get into the tube. The column of mercury invariably fell to about twenty-eight inches, leaving an empty space (Torricellian vacuum) above its level . Role of Barometer in the Improvement Of Human Life Barometer became a commonly used instrument for weather predictions. This further helped in weather forecasting which helped farmers, geologists, scientists and people in general As barometers measure air pressure, they were also used for measuring altitude, or height above the ground, such as the height of a mountain, and they were often used to measure altitude aboard a hot air balloon. They are also used by miners in caves to determine the depth of a mine. The barometer is today one of the most important scientific instruments, while the Torricellian method of getting a very high vacuum is still often employed.

Other Inventions Evangelista Torricelli - The History of the Barometer The History of the Barometer The History of the Barometer Evangelista Torricelli invented the mercurial barometer Malcolm Piers/ The Image Bank/ Getty Images By Mary Bellis Updated February 03, 2016. Barometer - Pronunciation: [b u rom´ u t u r] - a barometer is an instrument for measuring atmospheric pressure. Two common types are the aneroid barometer and the mercurial barometer (invented first). Evangelista Torricelli invented the first barometer, known as the "Torricelli's tube". Biography - Evangelista Torricelli Evangelista Torricelli was born October 15, 1608, in Faenza, Italy and died October 22, 1647 in Florence, Italy. He was a physicist and mathematician. In 1641, Evangelista Torricelli moved to Florence to assist the astronomer Galileo . The Barometer It was Galileo that suggested Evangelista Torricelli use mercury in his vacuum experiments.

Torricelli filled a four-foot long glass tube with mercury and inverted the tube into a dish. Some of the mercury did not escape from the tube and Torricelli observed the vacuum that was created. Evangelista Torricelli became the first scientist to create a sustained vacuum and to discover the principle of a barometer. continue reading below our video What to Do If You Can't Pay Your Student Loans Torricelli realized that the variation of the height of the mercury from day to day was caused by changes in the atmospheric pressure. Torricelli built the first mercury barometer around 1644. Evangelista Torricelli - Other Research Evangelista Torricelli also wrote on the quadrature of the cycloid and conics, the rectifications of the logarithmic spiral, the theory of the barometer, the value of gravity found by observing the motion of two weights connected by a string passing over a fixed pulley, the theory of projectiles and the motion of fluids. Lucien Vidie - Aneroid Barometer In 1843, the French scientist Lucien Vidie invented the aneroid barometer.

A aneroid barometer "registers the change in the shape of an evacuated metal cell to measure variations on the atmospheric pressure." Aneriod means fluidless, no liquids are used, the metal cell is usually made of phosphor bronze or beryllium copper. Related Instruments An altimeter is an aneroid barometer that measures altitude. Meteorologists use an altimeter that measures the altitude with respect to sea level pressure. A barograph is an aneroid barometer that gives a continuous reading of atmospheric pressures on graph paper. Torricelli biography Version for printing Evangelista Torricelli's parents were Gaspare Torricelli and Caterina Angetti. It was a fairly poor family with Gaspare being a textile worker. Evangelista was the eldest of his parents three children, having two younger brothers at least one of whom went on to work with cloth. It is greatly to his parents' credit that they saw that their eldest son had remarkable talents and, lacking the resources to provide an education for him themselves, they sent him to his uncle who was a Camaldolese monk. Brother Jacopo saw that Evangelista was given a sound education until he was old enough to enter a Jesuit school.

Torricelli entered a Jesuit College in 1624 and studied mathematics and philosophy there until 1626. It is not entirely clear at which College he studied, with most historians believing that he attended the Jesuit College in Faenza, while some believe that he entered the Collegio Romano in Rome. What is undoubtedly the case is that after study at the Jesuit College he was then in Rome. Certain facts are clear, namely that Torricelli's father died in or before 1626 and that his mother moved to Rome for she was certainly living there in 1641 at the time of her death. Torricelli's two brothers also moved to Rome and again we know for certain that they were living there in 1647. The most likely events seem to be that after Gaspare Torricelli died, Caterina and her two younger sons moved to Rome to be with Evangelista who was either already living there or about to move to that city. At the Jesuit College Torricelli showed that he had outstanding talents and his uncle, Brother Jacopo, arranged for him to study with Benedetto Castelli.

Castelli, who like Jacopo was a Camaldolese monk, taught at the University of Sapienza in Rome. Sapienza was the name of the building which the University of Rome occupied at this time and it gave its name to the University. There is no evidence that Torricelli was actually enrolled at the university, and it is almost certain that he was simply being taught by Castelli as a private arrangement. As well as being taught mathematics, mechanics, hydraulics, and astronomy by Castelli, Torricelli became his secretary and held this post from 1626 to 1632. It was an arrangement which meant that he worked for Castelli in exchange for the tuition he received. Much later he took over Castelli's teaching when he was absent from Rome. There does still exist a letter which Torricelli wrote to Galileo on 11 September 1632 and it gives us some very useful information about Torricelli's scientific progress. Galileo had written to Castelli but, since Castelli was away from Rome at the time, his secretary Torricelli wrote to Galileo to explain this fact.

Torricelli was an ambitious young man and he greatly admired Galileo , so he took the opportunity to inform Galileo of his own mathematical work. Torricelli began by Galileo Galileo that he was a professional mathematician and that he had studied the classical texts of Apollonius , Archimedes and Theodosius . He had also read almost everything that the contemporary mathematicians Brahe , Kepler and Longomontanus had written and, he told Galileo , he was convinced by the theory of Copernicus that the Earth revolved round the sun. Moreover, he had carefully studied Dialogue Concerning the Two Chief Systems of the World - Ptolemaic and Copernican which Galileo had published about six months before Torricelli wrote his letter. It was clear from his letter that Torricelli was fascinated by astronomy and was a strong supporter of Galileo . However the Inquisition banned the sale of the Dialogue and ordered Galileo to appear in Rome before them. After Galileo's trial in 1633, Torricelli realised that he would be on dangerous ground were he to continue with his interests in the Copernican theory so he deliberately shifted his attention onto mathematical areas which seemed less controversial.

During the next nine years he served as secretary to Giovanni Ciampoli, a friend of Galileo , and possibly a number of other professors. We do not know where Torricelli lived during this period but, as Ciampoli served as governor of a number of cities in Umbria and the Marches, it is likely that he lived for periods in Montalto, Norcia, San Severino and Fabriano. By 1641 Torricelli had completed much of the work which he was to publish in three parts as Opera geometrica Ⓣ in 1644. We shall give more details of this work later in this biography, but for the moment we are interested in the second of the three parts De motu gravium Ⓣ . This basically carried on developing Galileo 's study of the parabolic motion of projectiles which had appeared in Discourses and mathematical demonstrations concerning the two new sciences published in 1638. Torricelli was certainly in Rome in early 1641 when he asked Castelli for his opinion on De motu gravium.

Castelli was so impressed that he wrote to Galileo himself, at this time living in his home in Arcetri near Florence, watched over by officers from the Inquisition. In April 1641 Castelli travelled from Rome to Venice and, on the way, stopped in Arcetri to give Galileo a copy of Torricelli's manuscript and suggest that he employed him as an assistant. Torricelli remained in Rome while Castelli was on his travels and gave his lectures in his place. Although Galileo was keen to have Torricelli's assistance there was a delay before this could happen. On the one hand Castelli did not return to Rome for some time, while the death of Torricelli's mother further delayed his departure. On 10 October 1641 Torricelli arrived at Galileo 's house in Arcetri. He lived there with Galileo and also with Viviani who was already assisting Galileo . He only had a few months with Galileo, however, before that famous scientist died in January 1642.

Delaying his return to Rome for a while after Galileo died, Torricelli was appointed to succeed Galileo as the court mathematician to Grand Duke Ferdinando II of Tuscany. He did not receive the title of Court Philosopher to the Grand Duke which Galileo had also held. He held this post until his death living in the ducal palace in Florence. In looking at Torricelli's achievements we should first put his mathematical work into context. Another pupil of Castelli, Bonaventura Cavalieri , held the chair of mathematics at Bologna. Cavalieri presented his theory of indivisibles in Geometria indivisibilis continuorum nova published in 1635. The method was a development of Archimedes ' method of exhaustion incorporating Kepler 's theory of infinitesimally small geometric quantities. This theory allowed Cavalieri to find, in a simple and rapid way, the area and volume of various geometric figures. Torricelli studied the methods being proposed by Cavalieri and at first was suspicious of them. However, he soon became convinced that these powerful methods were correct and began to develop them further himself.

In fact he used a combination of the new and old methods, using the method of indivisibles to discover his results, but often giving a classical geometrical proof of them. He gave this not because he doubted the correctness of the method of indivisibles, rather because he wanted to give a proof:- ... according to the usual method of the ancient geometers ... so that readers not familiar with the new methods would still be convinced of the correctness of his results. By 1641 he had proved a number of impressive results using the methods which he would publish three years later. He examined the three dimensional figures obtained by rotating a regular polygon about an axis of symmetry. Torricelli also computed the area and centre of gravity of the cycloid. His most remarkable results, however, resulted from his extension of Cavalieri 's method of indivisibles to cover curved indivisibles. With these tools he was able to show that rotating the unlimited area of a rectangular hyperbola between the y-axis and a fixed point on the curve, resulted in a finite volume when rotated round the y-axis. Notice that we have stated this result in the modern notation of coordinate geometry which was totally unavailable to Torricelli.

This last result, described in [ 1 ] as:- ... a gem of the mathematical literature of the time ... is considered in detail in [ 23 ] where it is noted that, immediately after its publication in 1644, the result aroused great interest and admiration because it went totally against the intuition of mathematicians of the period. We mentioned Torricelli's results on the cycloid and these resulted in a dispute between him and Roberval . The article [ 19 ] discusses:- ... a letter dated October 1643, by which Torricelli gets in touch with Roberval and reports to him about his views and results on the centre of gravity of the parabola, the semigeneral parabolas, the surface of the cycloid and its history, the solid of revolution generated by a conic and the hyperbolic acute solid. We should also note another fine contribution made by Torricelli was in solving a problem due to Fermat when he determined the point in the plane of a triangle so that the sum of its distances from the vertices is a minimum (known as the isogonic centre of the triangle).

This contribution, described in detail in [ 20 ], is summarised in that paper as follows:- Around 1640, Torricelli devised a geometrical solution to a problem, allegedly first formulated in the early 1600s by Fermat : 'given three points in a plane, find a fourth point such that the sum of its distances to the three given points is as small as possible'. Torricelli was the first person to create a sustained vacuum and to discover the principle of a barometer. In 1643 he proposed an experiment, later performed by his colleague Vincenzo Viviani , that demonstrated that atmospheric pressure determines the height to which a fluid will rise in a tube inverted over the same liquid. This concept led to the development of the barometer. Torricelli wrote a letter to his friend Michelangelo Ricci , who like him had been a student of Castelli, on 11 June 1644. At this stage Torricelli was in Florence, writing to his friend Ricci who was in Rome. I have already called attention to certain philosophical experiments that are in progress ...

relating to vacuum, designed not just to make a vacuum but to make an instrument which will exhibit changes in the atmosphere, which is sometimes heavier and denser and at other times lighter and thinner. Many have argued that a vacuum does not exist, others claim it exists only with difficulty in spite of the repugnance of nature; I know of no one who claims it easily exists without any resistance from nature. Whether a vacuum existed was a question which had been argued over for centuries. Aristotle had simply claimed that a vacuum was a logical contradiction, but difficulties with this had led Renaissance scientists to modify this to the claim that 'nature abhors a vacuum' which is in line with those who Torricelli suggests believe a vacuum exists despite 'the repugnance of nature'. Galileo had observed the experimental evidence that a suction pump could only raise water by about nine metres but had given an incorrect explanation based on the "force created by a vacuum". Torricelli then described an experiment and gives for the first time the correct explanation:- We have made many glass vessels ... with tubes two cubits long. These were filled with mercury, the open end was closed with the finger, and the tubes were then inverted in a vessel where there was mercury.

.. We saw that an empty space was formed and that nothing happened in the vessel where this space was formed ... I claim that the force which keeps the mercury from falling is external and that the force comes from outside the tube. On the surface of the mercury which is in the bowl rests the weight of a column of fifty miles of air. Is it a surprise that into the vessel, in which the mercury has no inclination and no repugnance, not even the slightest, to being there, it should enter and should rise in a column high enough to make equilibrium with the weight of the external air which forces it up? He attempted to examine the vacuum which he was able to create and test whether sound travelled in a vacuum. He also tried to see if insects could live in the vacuum. However he seems not to have succeeded with these experiments. In De motu gravium Ⓣ which was published as part of Torricelli's 1644 Opera geometrica Ⓣ , Torricelli also proved that the flow of liquid through an opening is proportional to the square root of the height of the liquid, a result now known as Torricelli's theorem.

It was another remarkable contribution which has led to some suggesting that this result makes him the founder of hydrodynamics. Also in De motu gravium Torricelli studied projectile motion. He developed Galileo 's ideas on the parabolic trajectory of projectiles launched horizontally, giving a theory for projectiles launched at any angle. He also gave numerical tables which would help gunners find the correct elevation of their guns to give the required range. Three years later he received a letter from Renieri of Genoa who claimed that he had conducted some experiments which contradicted the theory of parabolic trajectories. The two corresponded on the topic with Torricelli saying that his theory was in fact based on ignoring certain effects which would make the experimental data slightly different. Torricelli not only had great skills in theoretical work but he also had great skill as a maker of instruments. He was a skilled lens grinder, making excellent telescopes and small, short focus, simple microscopes, and he seems to have learnt these techniques during the time he lived with Galileo . Gliozzi writes in [ 1 ]:- ... one of Torricelli's telescope lenses ... was examined in 1924 ... using a diffraction grating.

It was found to be of exquisite workmanship, sos much so that one face was seen to have been machined better than the mirror taken a reference surface ... In fact he made much money from his skill in lens grinding in the last period of his life in Florence and the Grand Duke gave him many gifts in return for scientific instruments. Much of Torricelli's mathematical and scientific work has not survived, mainly because he published only the one work we referred to above. In addition to letters which have survived which tell us important facts about his achievements, we also have some lectures which he gave. These were collected and published after his death and include one he gave when he was elected to the Accademia della Crusca in 1642 and seven others given to the Academy during the next few years. One of these was on the wind and it is important for again Torricelli was the first to give the correct scientific explanation when he proposed that [ 1 ]:- ... winds are produced by differences of air temperature, and hence density, between two regions of the earth.

We referred above to the argument between Torricelli and Roberval concerning the cycloid, and in 1646 Torricelli began gathering together the correspondence which had passed between the two on the topic. It is clear that Torricelli was an honest man who felt that he needed to publish the material to present the truth to the world. There can be no doubt that these two great mathematicians had made similar discoveries about the cycloid but neither had been influenced by the other's ideas. However, before he completed the task of preparing the correspondence for publication Torricelli contracted typhoid in October 1647 died a few days later at the young age of 39 while in his prime as a research mathematician and scientist. Hours before his death he tried to ensure that his unpublished manuscripts and letters be given to someone to prepare for publication and he entrusted them to his friend Ludovico Serenai. After neither Castelli nor Michelangelo Ricci would undertake the task and although Viviani did agree to prepare the material for publication he failed to accomplish the task. Some of Torricelli's manuscripts were lost and it was not until 1919 that the remaining material was published as Torricelli had wished.

His collected works were published with Gino Loria and Guiseppe Vassura as editors, three volumes being published in 1919 and the fourth volume in 1944 nearly 300 years after Torricelli's death. Sadly material left by him, bearing his own signature, was destroyed in the Torricelli Museum in Faenza in 1944. Torricelli's remarkable contributions mean that had he lived he would certainly have made other outstanding mathematical discoveries. Collections of paradoxes which arose through inappropriate use of the new calculus were found in his manuscripts and show the depth of his understanding. In fact he may indeed have made contributions which will never be known, for the full range of his ideas were never properly recorded.

Article by: J J O'Connor and E F Robertson Click on this link to see a list of the Glossary entries for this page Evangelista Torricelli: The Invention of the Barometer The Invention of the Barometer Hands On Activity: Make Your Own Barometer Zuse Konrad Evangelista Torricelli (1608-1647) on an Italian Stamp Early in its history, in the seventeenth century, the barometer was purely a laboratory experiment, and it was primarily used not to measure air pressure, but to create an alleged vacuum (above the column of liquid in a tube). During the time from the creation of the first barometer to the acceptance of the barometer as an instrument for measuring air pressure, debates raged across borders via letter, experiments were competitively carried out by the greatest minds of the day, and pages were filled by scientists trying to explain the phenomena observed in experiments with barometers. It was traditionally thought (especially by the Aristotelians) that the air did not have weight - that is, that the miles of air above us don't weigh down on the air at our level. Even Galileo Galilei had accepted the weightlessness of air as a simple truth.

Evangelista Torricelli, an Italian mathematician and scientist, questioned that assumption, and proposed that the air had weight, and that it was the weight of the air (not the attractive force of the vacuum as many thought) which held (or rather, pushed) up the column of water. He thought that the level the water stayed at (thirty-four feet) was reflective of the force of the air's weight pushing on it (specifically, pushing on the water in the basin and thus limiting how much water can fall from the tube into it). In other words, he viewed the barometer as a balance, an instrument for measurement (as opposed to merely being an instrument to create a vacuum), and because he was the first to view it this way, he is traditionally considered the inventor of the barometer (in the sense in which we use the term now). The idea of using a heavier liquid then water was probably not Torricelli's own and Galileo (of whom Torricelli was briefly a student) himself may have suggested that other substances (including wine and mercury) would stop at a higher or lower level than water did.

Regardless of who came up with the idea, Torricelli was the first to seriously take it up as an experiment. Early in 1644, a friend of Torricelli carried out Torricelli's experiment, and it was seen that the mercury (which was known to be fourteen times heavier than water) stopped flowing into the basin when the level in the tube reached a height fourteen times smaller than that at which water stopped. Thus, Torricelli's ideas that the weight of the air from the atmosphere caused the liquid to stop falling seemed to be confirmed. Torricelli also noticed that the level of the fluid in the tube changed slightly each day and concluded that this was due to the changing pressure in the atmosphere. He wrote: "We live submerged at the bottom of an ocean of elementary air, which is known by incontestable experiments to have weight". At first, barometers used a column of water in a tube 34 ft (10.4 m) long. This inconvenient water column was soon replaced by Torricelli with mercury, which is denser than water and requires a tube about 3 ft (0.9 m) long.

The basic mercurial barometer consists of a glass tube, sealed at one end and filled with pure mercury. After that it is inverted in a small cup of mercury called the cistern. The mercury in the tube sinks slightly, creating above it a vacuum (the Torricellian vacuum). Atmospheric pressure on the surface of the mercury in the cistern supports the column in the tube, which varies in height with variations in atmospheric pressure and hence with changes in elevation, generally decreasing with increases in height above sea level. Schematic drawing of a simple mercury barometer with vertical mercury column and reservoir at base The mercury barometer's design gives rise to the expression of atmospheric pressure in inches: the pressure is quoted as the level of the mercury's height in the vertical column. 1 atmosphere is equivalent to about 29.9 inches of mercury. The use of this unit is still popular in the United States, although it has been disused in favor of SI or metric units in other parts of the world. Barometers of this type can usually measure atmospheric pressures in the range between 28 and 31 inches of mercury.

A barometer is commonly used for weather prediction, as high air pressure in a region indicates fair weather while low pressure indicates that storms are more likely. Localized high atmospheric pressure acts as a barrier to approaching weather systems, diverting their course. Low atmospheric pressure, on the other hand, represents the path of least resistance for a weather system, making it more likely that low pressure will be associated with increased storm activity. Make your own barometer Evangelista Torricelli Evangelista Torricelli Early Life: Evangelista Torricelli, an Italian man, and a physicist by occupation, initially studied at Jesuit schools in Faenza, near Ravenna. He was so good as a Physicist and a Mathematician that he was sent to Rome for further studies under Benedetto Castelli’s direction. Torricelli was introduced to Galileo by Benedetto Castelli and there Torricelli spent his time being Galileo’s assistant and secretary for a last few months of Galileo’s life. After Galileo passed away in January 1942, Torricelli was offered a position as a court mathematician and philosopher, Galileo’s old position, by the Grand Duke of Tuscany. This position was held by Torricelli till his death.

Advertisements Contributions and Achievements: Torricelli, also known as the father of hydrodynamics by Ernst Mach, was very famous for his study of the motion of fluids. He also carried out experiments of gases although the term was not invented by then. This led him to invent the Mercury Barometer, most important of his inventions. The invention took place by conducting an experiment on the air pressure and vacuum. Back then, the nature of vacuum was a debatable issue. Aristotle, a Greek philosopher and scientist, believed that vacuum could not exist as he said, “Nature abhors a vacuum.” On the other hand, Galileo believed that vacuum could exist and he explained the mechanism of the suction in a water pump that it was the vacuum that produced the action, and not the air pressure of the liquid being pumped. Galileo also felt the air was weightless. The debaters noticed that the suction pumps, regardless of the size and power, in mines could not raise water for more than eighteen bracci which is about 30 feet or 9 m. Why did the water not flow to the maximum if nature really abhorred vacuum? That’s when Torricelli invented the barometer while explaining the phenomenon.

Barometer was a great invention in the field of physics of atmosphere and the behavior of gases. He also contributed to meteorology by suggesting wind was caused by differences in the density of air, which is caused by the variations in the air temperature, and not by ‘Exhalations’. To represent the mechanism of the suction pump in a small tube, he took heavier liquids like honey, sea water and mercury etc. instead of pure water. Torricelli used relatively smaller tubes, which were sealed at one end, for conducting the experiment with mercury. He filled about a meter of such tube with mercury and sealed the open end with his thumb before inverting the tube. He then submerged the tube into the dish of mercury. On inverting, the mercury in the tube dropped half way down and left an empty space at the top and a column of mercury in the tube about one and one-third bracci in height. The dispute about the nature of vacuum was settled when Torricelli represented the experiment in this way: The weight of air pushing down on the dish of mercury prevented the mercury in the tube from falling out completely and the mercury was not pulled by the mercury. The weight could retain about thirty inches of mercury in the tube.

Torricelli observed that such pumps could cause the water to move upwards, by evacuating the air pressure above a column of water, but that the water would move up only as far as the air pressure below pushed it up. The water came to a stop when the weight of the water exceeded the power of the air pressure below no matter how hard the pump worked. This also came to Torricelli’s notice that the height of the mercury varied by the passage of time. It was due to changes in the air pressure overtime that this happened. A French scientist Marin Mersenne (1588-1648) visited Torricelli in 1644 and took with him the idea of mercury barometer to his friend Blaise Pascal. Pascal also agreed to the fact that the air pressure and the altitude were inversely proportional. It was shown by Pascal practically that the barometric pressure did indeed decrease as one ascended a mountain. This showed that Torricelli’s theory was absolutely correct. Vincenzo Antinori drew an analogy a few years later that Torricelli’s invention of Barometer was to Physics what the invention of telescope was to Physics.

Torricelli had also made improvements to the telescope which was an instrument used by Galileo for astronomy. Torricelli could grind lenses with such accuracy that he produced some of the finest telescopes. Torricelli contributed a great deal to the field of mathematics which was an important contribution in the scientific history. He worked on the equations of curves, solids, and their rotations to fill in the missing parts between the Greek geometry and Calculus based on the works Francesco Cavalieri’s “of indivisibles. Calculus was given its first complete formulation by Isaac Newton and Gottfried Wilhelm Leibniz, along with the works of René Descartes, Pierre de Fermat, Gilles Personne de Roberval and others. Later Life: Torricelli carried on with the tradition of Italian scientific pioneering, although he was not as good as his older contemporary Galileo. The tradition did not last long after his death and by the mid of seventeenth century or the beginning of the next century, Northern Europe had become the center of scientific progress.

Advertisements 10 of Science’s Best BAD ideas – Part… Galileo Galilei Torricelli, Evangelista (1608-1647) -- from Eric Weisstein's World of Scientific Biography Torricelli, Evangelista (1608-1647) Italian physicist who served as the secretary and companion of Galileo during the last three months of his life. In investigating vacuums , he constructed the first mercury barometer in 1643-1644. He correctly attributed the fact that the height of the mercury was only 1/14 that of a water barometer to the fact that mercury is fourteen times as dense as water. He also noticed that the level of mercury varied from day to day, and observed that the space above the mercury in the barometer must contain a vacuum . Torricelli also developed the concepts of momentum When was Barometer invented? – When was it invented? raman November 18, 2011 No Comments on When was Barometer invented? Between the year 1640 and 1643 a water barometer was invented by an Italian mathematician Gasparo Berti.

In the year 1643, an Italian physicist Evangelista Torricelli invented the mercury barometer. The French scientist Lucien Vidie invented the aneroid barometer in 1843 by using a spring balance. Barometer is a scientific instrument that measures pressure of air. Evangelista Torricelli: Biography & Inventor of Barometer | Online Homework Help | SchoolWorkHelper Evangelista Torricelli: Biography & Inventor of Barometer You are here: PDF Evangelista Torricelli was born October 15th, 1608 in what is now known as Faenza, Italy. Little information is known about his early years of life. In 1624 he entered the Jesuit College of Faenza, then moved on to the Collegio Romano in Rome. Here his talents and intellect were recognized and he was then moved on to the University of Sapienza, now known as the University of Rome, to be taught by the great Italian professor, Castelli. Also during this time, Torricelli served as Castelli’s secretary from 1636 to 1642.

Over the next nine years he served a large number of professors as a secretary and learned much from each of them. First of all, he invented the barometer, a device that is still used today to measure the amount of atmospheric pressure, which is helpful for detecting inclement weather. Secondly, he is the namesake for a unit of pressure known as the Torr. The invention of the barometer is considered by most to be his biggest contribution to science. While serving as Galileo’s secretary from 1641 to 1642, he learned many things about pressure and temperature from the great scientist. Galileo had been struggling to create a water thermometer. He could not understand why water could not be suspended in a tube taller than 34 feet. After much research, Torricelli discovered the answer: air has weight. The water could not stay in the tube due to the incredible amount of pressure being exerted on it by the air above. His invention of the mercury filled barometer in 1643 proved this theory and also proved the existence of air pressure. In his lifetime, Torricelli had many great accomplishments and contributions to the areas of science and mathematics.

He was the first man to create a sustained vacuum, which led to the discovery of the barometer. He proved that the flow of liquid through an opening is proportional to the square root of the height of the liquid, a theory that is now known as Torricelli’s theorem. He succeeded Galileo as the court mathematician to Grand Duke Ferdinando II of Tuscany. He also found the length of the arc of a cycloid, which is the curve that is traced by a point on the circumference of a rotating circle. In other mathematical areas, he determined the point in the plane of a triangle where the sum of its distances from the vertices is the smallest. This is also known as the isogonic center. In 1644 he published a book about his studies in projectile motion, entitled Opera Geometrica. Torricelli also had significant talents in the grinding of lenses for telescopes and microscopes. He supported himself in the final years of his life with these talents. On the evening of October 25th, 1647, Evangelista Torricelli died at the young age of 39 in the palace of Duke Ferdinando. He had fathered many important discoveries in his short life.

With the naming of the Torr. After him, along with the moon’s Crater Torricelli and Rue Torricelli, a street in Paris, he is surely to never be forgotten by the scientific community or the rest of the world. Related posts: Evangelista Torricelli | Biography, Inventions and Facts Evangelista Torricelli Evangelista Torricelli invented “Barometer” Evangelista Torricelli was an Italian physicist and mathematician, best known for his invention of the barometer. Torricelli was born to a poor family in 1608 and to make matters worse, his father passed away when Torricelli was just a child. The family perceived that Torricelli was a gifted child and so he was given to the care of an uncle who was a Camaldolese monk. Torricelli’s uncle arranged for him to study with Benedetto Castelli, a mathematics professor at the University of Sapienza in Rome. Castelli taught him mathematics, mechanics, hydraulics, and astronomy and in return Torricelli acted as his assistant and secretary. He held this post for six years until 1632.

Torricelli was greatly inspired by the work of Galileo and he read all of his books. He was an avid student of astronomy, however he deliberately shifted his focus solely towards mathematics. This was because he wanted to avoid having the same fate as Galileo, who was taken to trial in Rome in 1633 for proposing supposedly controversial theories. Torricelli decided that mathematics was a safer choice than astronomy and so he pursued that instead. During the time that Torricelli worked for Castelli, Galileo had written a letter to Castelli. This letter was answered by Torricelli instead since Castelli was away from Rome at that time. In his reply, Torricelli expressed admiration for Galileo’s work and put forward some of his own theories. Galileo was impressed and invited Torricelli to come and work as his assistant. Torricelli did not immediately accept this; only much later did he go to live with Galileo, which was not for very long since Galileo died three months later. After Galileo’s death, Torricelli was invited by Grand Duke Ferdinando II of Tuscany to work as the court mathematician.

Torricelli accepted, and held this post until his death in 1647. Evangelista Torricelli made several important contributions in the fields of mathematics and physics. One of the biggest and most controversial debates in those days was about the existence of vacuums, a possibility that had been refuted by earlier scientists such as Aristotle. First Galileo and subsequently Torricelli were of the view that vacuums did in fact exist. Torricelli set up an experiment involving glass tubes filled with mercury (as it was denser than water) and thus became the first person to create a sustained vacuum. This led to the invention of the Mercury Barometer, an instrument used to measure atmospheric pressure. The development of the barometer was a monumental achievement in physics, and it is still widely in use today. His other contributions include his work on the equations of curves, formulating Torricelli’s Law about the speed of a fluid flowing out of an opening and being the first person to give a scientific explanation for the cause of wind – which he said was caused by differences in air temperature and density between two areas. His other areas of interest included geometry, infinite number series, fluid and projectile motion, calculus and mechanics.

The “torr”, a unit of pressure, is named after him. Torricelli published a number of manuscripts on geometry, physics and astronomy, most of which are preserved in Florence, Italy. Not only was he a great theoretical scientist, he was also extremely skilled at making lenses and mechanical instruments such as microscopes and telescopes. Some of these lenses, engraved with his name, are still preserved in Florence. How Torricelli first invented the barometer - Howard Walwyn Fine Antique Clocks How Torricelli first invented the barometer Posted on 16 September 2015 Derived from the Greek words ‘baros’ and ‘metron’, meaning weight and measure respectively, the barometer is an instrument used to measure air pressure, and is extremely important in predicting weather patterns. During the beginning of the early 17th century, several Italian scientists were in fact working to discover the principles of vacuums and air pressure. Galileo was recognised as the first to experiment with water-type vacuum apparatus in 1642, though this was solely to verify the ‘vacuum theory’ and was not applied to measuring air pressure.

Scientist Evangelista Torricelli studied the works of Galileo, and created the first publicised working barometer in 1643. In his development of the barometer, Torricelli utilised the principle of using a vacuum to measure the weight of the air – outdoor air pressure causes water in a partial vacuum to rise. The average outdoor air pressure would mean that the water would need to rise by 35 feet, and so Torricelli created a 35-foot high tube experiment in his home. This barometer prototype rose up out of the roof of his home, and Torricelli placed a dummy on top of it to chart the air pressure and weather changes. This large addition to his home caused much concern in his local neighbourhood, with many of the townsfolk believing he was up to some sort of sorcery. The 17th century was a time when science and religion were still in conflict, with religious clerics of the day against the notion of a vacuum in particular, as God was believed to be everywhere. Due to the rumours circulating throughout the neighbourhood, Torricelli realised he needed to be more discreet with his experiments, else he may run the risk of being arrested.

In order to shorten his barometer prototype, he needed to use a liquid heavier than water. Turning to the work of Galileo, he deducted that mercury was 14 times heavier than water, meaning that a tube only 32 inches high would be needed, rather than 35 feet. Unfortunately, due to the debate surrounding vacuums between religion and science, Torricelli went unrecognised for over a hundred years, and was buried in an unmarked grave with little fanfare upon his death. Every barometer that has followed, however, has followed his basic principles, and his work has opened up study in a new field of meteorology. His work has also inspired many of the antique barometers available from Howard Walwyn Fine Antique Clocks – visit our website to browse our excellent collection.

Question: In 1643 Evangalista Torichelli invented the world's first what?
Answer: Barometer