James Prescott Joule

James Prescott Joule

Overview
James Prescott Joule FRS (icon;
24 December 1818 – 11 October 1889) was an English physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...

 and brewer, born in Salford, Lancashire
Lancashire
Lancashire is a non-metropolitan county of historic origin in the North West of England. It takes its name from the city of Lancaster, and is sometimes known as the County of Lancaster. Although Lancaster is still considered to be the county town, Lancashire County Council is based in Preston...

. Joule studied the nature of heat
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...

, and discovered its relationship to mechanical work
Mechanical work
In physics, work is a scalar quantity that can be described as the product of a force times the distance through which it acts, and it is called the work of the force. Only the component of a force in the direction of the movement of its point of application does work...

 (see energy
Energy
In physics, energy is an indirectly observed quantity. It is often understood as the ability a physical system has to do work on other physical systems...

). This led to the theory of conservation of energy
Conservation of energy
The nineteenth century law of conservation of energy is a law of physics. It states that the total amount of energy in an isolated system remains constant over time. The total energy is said to be conserved over time...

, which led to the development of the first law of thermodynamics
First law of thermodynamics
The first law of thermodynamics is an expression of the principle of conservation of work.The law states that energy can be transformed, i.e. changed from one form to another, but cannot be created nor destroyed...

. The SI derived unit
SI derived unit
The International System of Units specifies a set of seven base units from which all other units of measurement are formed, by products of the powers of base units. These other units are called SI derived units, for example, the SI derived unit of area is square metre , and of density is...

 of energy, the joule
Joule
The joule ; symbol J) is a derived unit of energy or work in the International System of Units. It is equal to the energy expended in applying a force of one newton through a distance of one metre , or in passing an electric current of one ampere through a resistance of one ohm for one second...

, is named after him. He worked with Lord Kelvin
William Thomson, 1st Baron Kelvin
William Thomson, 1st Baron Kelvin OM, GCVO, PC, PRS, PRSE, was a mathematical physicist and engineer. At the University of Glasgow he did important work in the mathematical analysis of electricity and formulation of the first and second laws of thermodynamics, and did much to unify the emerging...

 to develop the absolute scale of temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...

, made observations on magnetostriction
Magnetostriction
Magnetostriction is a property of ferromagnetic materials that causes them to change their shape or dimensions during the process of magnetization. The variation of material's magnetization due to the applied magnetic field changes the magnetostrictive strain until reaching its saturation value, λ...

, and found the relationship between the current
Electric current
Electric current is a flow of electric charge through a medium.This charge is typically carried by moving electrons in a conductor such as wire...

 through resistance
Resistor
A linear resistor is a linear, passive two-terminal electrical component that implements electrical resistance as a circuit element.The current through a resistor is in direct proportion to the voltage across the resistor's terminals. Thus, the ratio of the voltage applied across a resistor's...

 and the heat dissipated, now called Joule's law
Joule's law
Joule's laws are a pair of laws concerning the heat produced by a current and the energy dependence of an ideal gas to that of pressure, volume, and temperature, respectively...

.


The son of Benjamin Joule (1784–1858), a wealthy brewer, and Alice Prescott Joule, James Prescott Joule was born in the house adjoining the Joule Brewery in New Bailey Street, Salford 24 December 1818.
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Encyclopedia
James Prescott Joule FRS (icon;
24 December 1818 – 11 October 1889) was an English physicist
Physicist
A physicist is a scientist who studies or practices physics. Physicists study a wide range of physical phenomena in many branches of physics spanning all length scales: from sub-atomic particles of which all ordinary matter is made to the behavior of the material Universe as a whole...

 and brewer, born in Salford, Lancashire
Lancashire
Lancashire is a non-metropolitan county of historic origin in the North West of England. It takes its name from the city of Lancaster, and is sometimes known as the County of Lancaster. Although Lancaster is still considered to be the county town, Lancashire County Council is based in Preston...

. Joule studied the nature of heat
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...

, and discovered its relationship to mechanical work
Mechanical work
In physics, work is a scalar quantity that can be described as the product of a force times the distance through which it acts, and it is called the work of the force. Only the component of a force in the direction of the movement of its point of application does work...

 (see energy
Energy
In physics, energy is an indirectly observed quantity. It is often understood as the ability a physical system has to do work on other physical systems...

). This led to the theory of conservation of energy
Conservation of energy
The nineteenth century law of conservation of energy is a law of physics. It states that the total amount of energy in an isolated system remains constant over time. The total energy is said to be conserved over time...

, which led to the development of the first law of thermodynamics
First law of thermodynamics
The first law of thermodynamics is an expression of the principle of conservation of work.The law states that energy can be transformed, i.e. changed from one form to another, but cannot be created nor destroyed...

. The SI derived unit
SI derived unit
The International System of Units specifies a set of seven base units from which all other units of measurement are formed, by products of the powers of base units. These other units are called SI derived units, for example, the SI derived unit of area is square metre , and of density is...

 of energy, the joule
Joule
The joule ; symbol J) is a derived unit of energy or work in the International System of Units. It is equal to the energy expended in applying a force of one newton through a distance of one metre , or in passing an electric current of one ampere through a resistance of one ohm for one second...

, is named after him. He worked with Lord Kelvin
William Thomson, 1st Baron Kelvin
William Thomson, 1st Baron Kelvin OM, GCVO, PC, PRS, PRSE, was a mathematical physicist and engineer. At the University of Glasgow he did important work in the mathematical analysis of electricity and formulation of the first and second laws of thermodynamics, and did much to unify the emerging...

 to develop the absolute scale of temperature
Temperature
Temperature is a physical property of matter that quantitatively expresses the common notions of hot and cold. Objects of low temperature are cold, while various degrees of higher temperatures are referred to as warm or hot...

, made observations on magnetostriction
Magnetostriction
Magnetostriction is a property of ferromagnetic materials that causes them to change their shape or dimensions during the process of magnetization. The variation of material's magnetization due to the applied magnetic field changes the magnetostrictive strain until reaching its saturation value, λ...

, and found the relationship between the current
Electric current
Electric current is a flow of electric charge through a medium.This charge is typically carried by moving electrons in a conductor such as wire...

 through resistance
Resistor
A linear resistor is a linear, passive two-terminal electrical component that implements electrical resistance as a circuit element.The current through a resistor is in direct proportion to the voltage across the resistor's terminals. Thus, the ratio of the voltage applied across a resistor's...

 and the heat dissipated, now called Joule's law
Joule's law
Joule's laws are a pair of laws concerning the heat produced by a current and the energy dependence of an ideal gas to that of pressure, volume, and temperature, respectively...

.

Early years



The son of Benjamin Joule (1784–1858), a wealthy brewer, and Alice Prescott Joule, James Prescott Joule was born in the house adjoining the Joule Brewery in New Bailey Street, Salford 24 December 1818. James was tutored at the family home 'Broomhill', Pendlebury
Pendlebury
Pendlebury is a suburban town in the City of Salford, in Greater Manchester, England. It lies to the northwest of Manchester city centre, northwest of Salford, and southeast of Bolton....

, near Salford, until 1834 when he was sent with his elder brother Benjamin, to study with John Dalton at the Manchester Literary and Philosophical Society
Manchester Literary and Philosophical Society
The Manchester Literary and Philosophical Society, popularly known as the Lit & Phil, is a learned society in Manchester, England.Established in 1781 as the Literary and Philosophical Society of Manchester, by Thomas Percival, Thomas Barnes and Thomas Henry, other prominent members have included...

. The pair only received two years' education in arithmetic
Arithmetic
Arithmetic or arithmetics is the oldest and most elementary branch of mathematics, used by almost everyone, for tasks ranging from simple day-to-day counting to advanced science and business calculations. It involves the study of quantity, especially as the result of combining numbers...

 and geometry
Geometry
Geometry arose as the field of knowledge dealing with spatial relationships. Geometry was one of the two fields of pre-modern mathematics, the other being the study of numbers ....

 before Dalton was forced to retire owing to a stroke
Stroke
A stroke, previously known medically as a cerebrovascular accident , is the rapidly developing loss of brain function due to disturbance in the blood supply to the brain. This can be due to ischemia caused by blockage , or a hemorrhage...

. However, Dalton's influence made a lasting impression as did that of his associates, chemist
Chemist
A chemist is a scientist trained in the study of chemistry. Chemists study the composition of matter and its properties such as density and acidity. Chemists carefully describe the properties they study in terms of quantities, with detail on the level of molecules and their component atoms...

 William Henry
William Henry (chemist)
William Henry was an English chemist.He was the son of Thomas Henry and was born in Manchester England. He developed what is known today as Henry's Law.-Life:...

 and Manchester engineers Peter Ewart
Peter Ewart
Peter Ewart was a British engineer who was influential in developing the technologies of turbines and theories of thermodynamics....

 and Eaton Hodgkinson
Eaton Hodgkinson
Eaton A. Hodgkinson was an English engineer, a pioneer of the application of mathematics to problems of structural design.-Early life:...

. Joule was subsequently tutored by John Davies
John Davies (lecturer)
John Davies or Davis was an English scientist in Victorian Manchester. He was a lecturer and private tutor who played an important role in the administration of some of the city's learned societies.-Career:...

. Fascinated by electricity
Electricity
Electricity is a general term encompassing a variety of phenomena resulting from the presence and flow of electric charge. These include many easily recognizable phenomena, such as lightning, static electricity, and the flow of electrical current in an electrical wire...

, he and his brother experimented by giving electric shocks to each other and to the family's servants.

Joule became a manager of the brewery and took an active role until the sale of the business in 1854. Science was a hobby but he soon started to investigate the feasibility of replacing the brewery's steam engine
Steam engine
A steam engine is a heat engine that performs mechanical work using steam as its working fluid.Steam engines are external combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be...

s with the newly invented electric motor
Electric motor
An electric motor converts electrical energy into mechanical energy.Most electric motors operate through the interaction of magnetic fields and current-carrying conductors to generate force...

. In 1838, his first scientific papers on electricity were contributed to Annals of Electricity, the scientific journal
Scientific journal
In academic publishing, a scientific journal is a periodical publication intended to further the progress of science, usually by reporting new research. There are thousands of scientific journals in publication, and many more have been published at various points in the past...

 founded and operated by Davies's colleague William Sturgeon
William Sturgeon
William Sturgeon was an English physicist and inventor who made the first electromagnets, and invented the first practical English electric motor.-Early Life :...

. He formulated Joule's laws in 1840 and hoped to impress the Royal Society
Royal Society
The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...

 but found, not for the last time, that he was perceived as a mere provincial dilettante. When Sturgeon moved to Manchester in 1840, Joule and he became the nucleus of a circle of the city's intellectuals. The pair shared similar sympathies that science and theology could and should be integrated. Joule went on to lecture at Sturgeon's Royal Victoria Gallery of Practical Science.

He went on to realise that burning a pound of coal in a steam engine produced five times as much duty as a pound of zinc
Zinc
Zinc , or spelter , is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element in group 12 of the periodic table. Zinc is, in some respects, chemically similar to magnesium, because its ion is of similar size and its only common oxidation state is +2...

 consumed in a Grove cell
Grove cell
The Grove cell was an early electric primary cell named after its inventor, British chemist William Robert Grove, and consisted of a zinc anode in dilute sulfuric acid and a platinum cathode in concentrated nitric acid, the two separated by a porous ceramic pot.-Cell details:The Grove cell voltage...

, an early electric battery
Battery (electricity)
An electrical battery is one or more electrochemical cells that convert stored chemical energy into electrical energy. Since the invention of the first battery in 1800 by Alessandro Volta and especially since the technically improved Daniell cell in 1836, batteries have become a common power...

. Joule's common standard of "economical duty" was the ability to raise one pound by a height of one foot, the foot-pound
Foot-pound force
The foot-pound force, or simply foot-pound is a unit of work or energy in the Engineering and Gravitational Systems in United States customary and Imperial units of measure. It is the energy transferred on applying a force of 1 pound-force through a displacement of 1 foot...

.

Joule was influenced by the thinking of Franz Aepinus
Franz Aepinus
Franz Ulrich Theodor Aepinus was a German and Russian natural philosopher. Aepinus is best known for his researches, theoretical and experimental, in electricity and magnetism.-Life:...

 and tried to explain the phenomena of electricity and magnetism
Magnetism
Magnetism is a property of materials that respond at an atomic or subatomic level to an applied magnetic field. Ferromagnetism is the strongest and most familiar type of magnetism. It is responsible for the behavior of permanent magnets, which produce their own persistent magnetic fields, as well...

 in terms of atom
Atom
The atom is a basic unit of matter that consists of a dense central nucleus surrounded by a cloud of negatively charged electrons. The atomic nucleus contains a mix of positively charged protons and electrically neutral neutrons...

s surrounded by a "calorific ether
Aether (classical element)
According to ancient and medieval science aether , also spelled æther or ether, is the material that fills the region of the universe above the terrestrial sphere.-Mythological origins:...

 in a state of vibration".

However, Joule's interest diverted from the narrow financial question to that of how much work could be extracted from a given source, leading him to speculate about the convertibility of energy
Energy
In physics, energy is an indirectly observed quantity. It is often understood as the ability a physical system has to do work on other physical systems...

. In 1843 he published results of experiments showing that the heat
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...

ing effect he had quantified in 1841 was due to generation of heat in the conductor and not its transfer from another part of the equipment. This was a direct challenge to the caloric theory
Caloric theory
The caloric theory is an obsolete scientific theory that heat consists of a self-repellent fluid called caloric that flows from hotter bodies to colder bodies. Caloric was also thought of as a weightless gas that could pass in and out of pores in solids and liquids...

 which held that heat could neither be created nor destroyed. Caloric theory had dominated thinking in the science of heat since it was introduced by Antoine Lavoisier
Antoine Lavoisier
Antoine-Laurent de Lavoisier , the "father of modern chemistry", was a French nobleman prominent in the histories of chemistry and biology...

 in 1783. Lavoisier's prestige and the practical success of Sadi Carnot
Nicolas Léonard Sadi Carnot
Nicolas Léonard Sadi Carnot was a French military engineer who, in his 1824 Reflections on the Motive Power of Fire, gave the first successful theoretical account of heat engines, now known as the Carnot cycle, thereby laying the foundations of the second law of thermodynamics...

's caloric theory of the heat engine
Heat engine
In thermodynamics, a heat engine is a system that performs the conversion of heat or thermal energy to mechanical work. It does this by bringing a working substance from a high temperature state to a lower temperature state. A heat "source" generates thermal energy that brings the working substance...

 since 1824 ensured that the young Joule, working outside either academia
Academia
Academia is the community of students and scholars engaged in higher education and research.-Etymology:The word comes from the akademeia in ancient Greece. Outside the city walls of Athens, the gymnasium was made famous by Plato as a center of learning...

 or the engineering profession, had a difficult road ahead. Supporters of the caloric theory readily pointed to the symmetry of the Peltier-Seebeck effect to claim that heat and current were convertible, at least approximately, by a reversible process.

The mechanical equivalent of heat


Joule wrote in his 1845 paper:

Joule here adopts the language of vis viva (energy), possibly because Hodgkinson had read a review of Ewart's On the measure of moving force to the Literary and Philosophical Society in April 1844.

Further experiments and measurements by Joule led him to estimate the mechanical equivalent of heat
Mechanical equivalent of heat
In the history of science, the mechanical equivalent of heat was a concept that had an important part in the development and acceptance of the conservation of energy and the establishment of the science of thermodynamics in the 19th century....

as 838 ft·lbf
Foot-pound force
The foot-pound force, or simply foot-pound is a unit of work or energy in the Engineering and Gravitational Systems in United States customary and Imperial units of measure. It is the energy transferred on applying a force of 1 pound-force through a displacement of 1 foot...

 of work to raise the temperature of a pound of water by one degree Fahrenheit. He announced his results at a meeting of the chemical section of the British Association for the Advancement of Science
British Association for the Advancement of Science
frame|right|"The BA" logoThe British Association for the Advancement of Science or the British Science Association, formerly known as the BA, is a learned society with the object of promoting science, directing general attention to scientific matters, and facilitating interaction between...

 in Cork
Cork (city)
Cork is the second largest city in the Republic of Ireland and the island of Ireland's third most populous city. It is the principal city and administrative centre of County Cork and the largest city in the province of Munster. Cork has a population of 119,418, while the addition of the suburban...

 in 1843 and was met by silence.

Joule was undaunted and started to seek a purely mechanical demonstration of the conversion of work into heat. By forcing water through a perforated cylinder, he was able to measure the slight viscous
Viscosity
Viscosity is a measure of the resistance of a fluid which is being deformed by either shear or tensile stress. In everyday terms , viscosity is "thickness" or "internal friction". Thus, water is "thin", having a lower viscosity, while honey is "thick", having a higher viscosity...

 heating of the fluid. He obtained a mechanical equivalent of 770 ft·lbf/Btu
British thermal unit
The British thermal unit is a traditional unit of energy equal to about 1055 joules. It is approximately the amount of energy needed to heat of water, which is exactly one tenth of a UK gallon or about 0.1198 US gallons, from 39°F to 40°F...

 (4.14 J
Joule
The joule ; symbol J) is a derived unit of energy or work in the International System of Units. It is equal to the energy expended in applying a force of one newton through a distance of one metre , or in passing an electric current of one ampere through a resistance of one ohm for one second...

/cal
Calorie
The calorie is a pre-SI metric unit of energy. It was first defined by Nicolas Clément in 1824 as a unit of heat, entering French and English dictionaries between 1841 and 1867. In most fields its use is archaic, having been replaced by the SI unit of energy, the joule...

). The fact that the values obtained both by electrical and purely mechanical means were in agreement to at least one order of magnitude
Order of magnitude
An order of magnitude is the class of scale or magnitude of any amount, where each class contains values of a fixed ratio to the class preceding it. In its most common usage, the amount being scaled is 10 and the scale is the exponent being applied to this amount...

 was, to Joule, compelling evidence of the reality of the convertibility of work into heat.

Joule now tried a third route. He measured the heat generated against the work done in compressing a gas. He obtained a mechanical equivalent of 823 ft·lbf/Btu (4.43 J/cal). In many ways, this experiment offered the easiest target for Joule's critics but Joule disposed of the anticipated objections by clever experimentation. However, his paper was rejected by the Royal Society
Royal Society
The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...

 and he had to be content with publishing in the Philosophical Magazine
Philosophical Magazine
The Philosophical Magazine is one of the oldest scientific journals published in English. Initiated by Alexander Tilloch in 1798, in 1822 Richard Taylor became joint editor and it has been published continuously by Taylor & Francis ever since; it was the journal of choice for such luminaries as...

. In the paper he was forthright in his rejection of the caloric reasoning of Carnot and Émile Clapeyron, but his theological
Theology
Theology is the systematic and rational study of religion and its influences and of the nature of religious truths, or the learned profession acquired by completing specialized training in religious studies, usually at a university or school of divinity or seminary.-Definition:Augustine of Hippo...

 motivations also became evident:
In 1845, Joule read his paper On the mechanical equivalent of heat to the British Association meeting in Cambridge
Cambridge
The city of Cambridge is a university town and the administrative centre of the county of Cambridgeshire, England. It lies in East Anglia about north of London. Cambridge is at the heart of the high-technology centre known as Silicon Fen – a play on Silicon Valley and the fens surrounding the...

. In this work, he reported his best-known experiment, involving the use of a falling weight, in which gravity does the mechanical work, to spin a paddle-wheel in an insulated barrel of water which increased the temperature. He now estimated a mechanical equivalent of 819 ft·lbf/Btu (4.41 J/cal).

In 1850, Joule published a refined measurement of 772.692 ft·lbf/Btu (4.159 J/cal), closer to twentieth century estimates.

Reception and priority



For the controversy over priority with Mayer, see Mechanical equivalent of heat: Priority


Much of the initial resistance to Joule's work stemmed from its dependence upon extremely precise
Accuracy and precision
In the fields of science, engineering, industry and statistics, the accuracy of a measurement system is the degree of closeness of measurements of a quantity to that quantity's actual value. The precision of a measurement system, also called reproducibility or repeatability, is the degree to which...

 measurement
Measurement
Measurement is the process or the result of determining the ratio of a physical quantity, such as a length, time, temperature etc., to a unit of measurement, such as the metre, second or degree Celsius...

s. He claimed to be able to measure temperatures to within of a degree Fahrenheit (3 mK). Such precision was certainly uncommon in contemporary experimental physics but his doubters may have neglected his experience in the art of brewing and his access to its practical technologies. He was also ably supported by scientific instrument
Measuring instrument
In the physical sciences, quality assurance, and engineering, measurement is the activity of obtaining and comparing physical quantities of real-world objects and events. Established standard objects and events are used as units, and the process of measurement gives a number relating the item...

-maker John Benjamin Dancer
John Benjamin Dancer
John Benjamin Dancer was a scientific instrument maker and inventor of microphotography. He also pioneered stereography. By 1835, he controlled his father's instrument making business. He was responsible for various inventions, but did not patent many of his ideas. In 1852, he invented the...

.

However, in Germany, Hermann Helmholtz became aware both of Joule's work and the similar 1842 work of Julius Robert von Mayer
Julius Robert von Mayer
Julius Robert von Mayer was a German physician and physicist and one of the founders of thermodynamics...

. Though both men had been neglected since their respective publications, Helmholtz's definitive 1847 declaration of the conservation of energy
Conservation of energy
The nineteenth century law of conservation of energy is a law of physics. It states that the total amount of energy in an isolated system remains constant over time. The total energy is said to be conserved over time...

 credited them both.

Also in 1847, another of Joule's presentations at the British Association in Oxford
Oxford
The city of Oxford is the county town of Oxfordshire, England. The city, made prominent by its medieval university, has a population of just under 165,000, with 153,900 living within the district boundary. It lies about 50 miles north-west of London. The rivers Cherwell and Thames run through...

 was attended by George Gabriel Stokes
George Gabriel Stokes
Sir George Gabriel Stokes, 1st Baronet FRS , was an Irish mathematician and physicist, who at Cambridge made important contributions to fluid dynamics , optics, and mathematical physics...

, Michael Faraday
Michael Faraday
Michael Faraday, FRS was an English chemist and physicist who contributed to the fields of electromagnetism and electrochemistry....

, and the precocious and maverick William Thomson
William Thomson, 1st Baron Kelvin
William Thomson, 1st Baron Kelvin OM, GCVO, PC, PRS, PRSE, was a mathematical physicist and engineer. At the University of Glasgow he did important work in the mathematical analysis of electricity and formulation of the first and second laws of thermodynamics, and did much to unify the emerging...

, later to become Lord Kelvin, who had just been appointed professor of natural philosophy
Natural philosophy
Natural philosophy or the philosophy of nature , is a term applied to the study of nature and the physical universe that was dominant before the development of modern science...

 at the University of Glasgow
University of Glasgow
The University of Glasgow is the fourth-oldest university in the English-speaking world and one of Scotland's four ancient universities. Located in Glasgow, the university was founded in 1451 and is presently one of seventeen British higher education institutions ranked amongst the top 100 of the...

. Stokes was "inclined to be a Joulite" and Faraday was "much struck with it" though he harboured doubts. Thomson was intrigued but skeptical.

Unanticipated, Thomson and Joule met later that year in Chamonix
Chamonix
Chamonix-Mont-Blanc or, more commonly, Chamonix is a commune in the Haute-Savoie département in the Rhône-Alpes region in south-eastern France. It was the site of the 1924 Winter Olympics, the first Winter Olympics...

. Joule married Amelia Grimes on 18 August and the couple went on honeymoon. Marital enthusiasm notwithstanding, Joule and Thomson arranged to attempt an experiment a few days later to measure the temperature difference between the top and bottom of the Cascade de Sallanches
Sallanches
Sallanches is a commune in the Haute-Savoie department in the Rhône-Alpes region in south-eastern France.-Media:Sallanches is mentioned in American author Willa Cather's 1935 novel Lucy Gayheart.-External links:*...

 waterfall, though this subsequently proved impractical.

Though Thomson felt that Joule's results demanded theoretical explanation, he retreated into a spirited defense of the Carnot-Clapeyron school. In his 1848 account of absolute temperature, Thomson wrote that "the conversion of heat (or caloric) into mechanical effect is probably impossible, certainly undiscovered" - but a footnote signaled his first doubts about the caloric theory, referring to Joule's "very remarkable discoveries". Surprisingly, Thomson did not send Joule a copy of his paper but when Joule eventually read it he wrote to Thomson on 6 October, claiming that his studies had demonstrated conversion of heat into work but that he was planning further experiments. Thomson replied on the 27th, revealing that he was planning his own experiments and hoping for a reconciliation of their two views. Though Thomson conducted no new experiments, over the next two years he became increasingly dissatisfied with Carnot's theory and convinced of Joule's. In his 1851 paper, Thomson was willing to go no further than a compromise and declared "the whole theory of the motive power of heat is founded on ... two ... propositions, due respectively to Joule, and to Carnot and Clausius".

As soon as Joule read the paper he wrote to Thomson with his comments and questions. Thus began a fruitful, though largely epistolary, collaboration between the two men, Joule conducting experiments, Thomson analysing the results and suggesting further experiments. The collaboration lasted from 1852 to 1856, its discoveries including the Joule-Thomson effect
Joule-Thomson effect
In thermodynamics, the Joule–Thomson effect or Joule–Kelvin effect or Kelvin–Joule effect describes the temperature change of a gas or liquid when it is forced through a valve or porous plug while kept insulated so that no heat is exchanged with the environment. This procedure is called a...

, and the published results did much to bring about general acceptance of Joule's work and the kinetic theory
Kinetic theory
The kinetic theory of gases describes a gas as a large number of small particles , all of which are in constant, random motion. The rapidly moving particles constantly collide with each other and with the walls of the container...

.

Kinetic theory


Kinetics is the science of motion. Joule was a pupil of Dalton and it is no surprise that he had learned a firm belief in the atomic theory
Atomic theory
In chemistry and physics, atomic theory is a theory of the nature of matter, which states that matter is composed of discrete units called atoms, as opposed to the obsolete notion that matter could be divided into any arbitrarily small quantity...

, even though there were many scientists of his time who were still sceptical. He had also been one of the few people receptive to the neglected work of John Herapath
John Herapath
John Herapath was an English physicist who gave a partial account of the kinetic theory of gases in 1820 though it was neglected by the scientific community at the time....

 on the kinetic theory of gases. He was further profoundly influenced by Peter Ewart
Peter Ewart
Peter Ewart was a British engineer who was influential in developing the technologies of turbines and theories of thermodynamics....

's 1813 paper On the measure of moving force.

Joule perceived the relationship between his discoveries and the kinetic theory of heat. His laboratory notebooks reveal that he believed heat to be a form of rotational, rather than translational motion.

Joule could not resist finding antecedents of his views in Francis Bacon, Sir Isaac Newton
Isaac Newton
Sir Isaac Newton PRS was an English physicist, mathematician, astronomer, natural philosopher, alchemist, and theologian, who has been "considered by many to be the greatest and most influential scientist who ever lived."...

, John Locke
John Locke
John Locke FRS , widely known as the Father of Liberalism, was an English philosopher and physician regarded as one of the most influential of Enlightenment thinkers. Considered one of the first of the British empiricists, following the tradition of Francis Bacon, he is equally important to social...

, Benjamin Thompson (Count Rumford) and Sir Humphry Davy
Humphry Davy
Sir Humphry Davy, 1st Baronet FRS MRIA was a British chemist and inventor. He is probably best remembered today for his discoveries of several alkali and alkaline earth metals, as well as contributions to the discoveries of the elemental nature of chlorine and iodine...

. Though such views are justified, Joule went on to estimate a value for the mechanical equivalent of heat of 1034 foot-pound from Rumford's publications. Some modern writers have criticised this approach on the grounds that Rumford's experiments in no way represented systematic quantitative measurements. In one of his personal notes, Joule contends that Mayer's measurement was no more accurate
Accuracy and precision
In the fields of science, engineering, industry and statistics, the accuracy of a measurement system is the degree of closeness of measurements of a quantity to that quantity's actual value. The precision of a measurement system, also called reproducibility or repeatability, is the degree to which...

 than Rumford's, perhaps in the hope that Mayer had not anticipated his own work.
Joule is attributed with explaining the Green Flash phenomenon in a letter to the Manchester Literary and Philosophical Society in 1869.

Honours




Joule died at home in Sale
Sale, Greater Manchester
Sale is a town within the Metropolitan Borough of Trafford, in Greater Manchester, England. Historically part of Cheshire, the town lies on flat ground on the south bank of the River Mersey, south of Stretford, northeast of Altrincham, and southwest of the city of Manchester...

 and is buried in Brooklands
Brooklands, Trafford
Brooklands is an area and electoral ward within Sale, in the Metropolitan Borough of Trafford, Greater Manchester, England. It is to the south-southwest of Manchester city centre and has a total resident population of 9,773....

 cemetery there. The gravestone is inscribed with the number "772.55", his climacteric 1878 measurement of the mechanical equivalent of heat, and with a quotation from the Gospel of John
Gospel of John
The Gospel According to John , commonly referred to as the Gospel of John or simply John, and often referred to in New Testament scholarship as the Fourth Gospel, is an account of the public ministry of Jesus...

, "I must work the works of him that sent me, while it is day: the night cometh, when no man can work" (9:4).
  • Fellow of the Royal Society
    Royal Society
    The Royal Society of London for Improving Natural Knowledge, known simply as the Royal Society, is a learned society for science, and is possibly the oldest such society in existence. Founded in November 1660, it was granted a Royal Charter by King Charles II as the "Royal Society of London"...

    , (1850);
    • Royal Medal
      Royal Medal
      The Royal Medal, also known as The Queen's Medal, is a silver-gilt medal awarded each year by the Royal Society, two for "the most important contributions to the advancement of natural knowledge" and one for "distinguished contributions in the applied sciences" made within the Commonwealth of...

      , (1852);
    • Copley Medal
      Copley Medal
      The Copley Medal is an award given by the Royal Society of London for "outstanding achievements in research in any branch of science, and alternates between the physical sciences and the biological sciences"...

       (1870);
  • President of Manchester Literary and Philosophical Society
    Manchester Literary and Philosophical Society
    The Manchester Literary and Philosophical Society, popularly known as the Lit & Phil, is a learned society in Manchester, England.Established in 1781 as the Literary and Philosophical Society of Manchester, by Thomas Percival, Thomas Barnes and Thomas Henry, other prominent members have included...

    , (1860);
  • President of the British Association for the Advancement of Science
    British Association for the Advancement of Science
    frame|right|"The BA" logoThe British Association for the Advancement of Science or the British Science Association, formerly known as the BA, is a learned society with the object of promoting science, directing general attention to scientific matters, and facilitating interaction between...

    , (1872, 1887);
  • Honorary degree
    Honorary degree
    An honorary degree or a degree honoris causa is an academic degree for which a university has waived the usual requirements, such as matriculation, residence, study, and the passing of examinations...

    s:
    • LL.D., Trinity College Dublin, (1857);
    • DCL
      Doctor of Civil Law
      Doctor of Civil Law is a degree offered by some universities, such as the University of Oxford, instead of the more common Doctor of Laws degrees....

      , University of Oxford
      University of Oxford
      The University of Oxford is a university located in Oxford, United Kingdom. It is the second-oldest surviving university in the world and the oldest in the English-speaking world. Although its exact date of foundation is unclear, there is evidence of teaching as far back as 1096...

      , (1860);
    • LL.D., University of Edinburgh
      University of Edinburgh
      The University of Edinburgh, founded in 1583, is a public research university located in Edinburgh, the capital of Scotland, and a UNESCO World Heritage Site. The university is deeply embedded in the fabric of the city, with many of the buildings in the historic Old Town belonging to the university...

      , (1871).
  • He received a civil list
    Civil list
    -United Kingdom:In the United Kingdom, the Civil List is the name given to the annual grant that covers some expenses associated with the Sovereign performing their official duties, including those for staff salaries, State Visits, public engagements, ceremonial functions and the upkeep of the...

     pension
    Pension
    In general, a pension is an arrangement to provide people with an income when they are no longer earning a regular income from employment. Pensions should not be confused with severance pay; the former is paid in regular installments, while the latter is paid in one lump sum.The terms retirement...

     of £200 per annum in 1878 for services to science;
  • Albert Medal
    Albert Medal (RSA)
    The Albert Medal of the Royal Society of Arts was instituted in 1864 as a memorial to Prince Albert, who had been President of the Society for 18 years. It was first awarded in 1864 for "distinguished merit in promoting Arts, Manufactures and Commerce"...

     of the Royal Society of Arts
    Royal Society of Arts
    The Royal Society for the encouragement of Arts, Manufacturers and Commerce is a British multi-disciplinary institution, based in London. The name Royal Society of Arts is frequently used for brevity...

    , (1880).
  • There is a memorial to Joule in the north choir aisle of Westminster Abbey
    Westminster Abbey
    The Collegiate Church of St Peter at Westminster, popularly known as Westminster Abbey, is a large, mainly Gothic church, in the City of Westminster, London, United Kingdom, located just to the west of the Palace of Westminster. It is the traditional place of coronation and burial site for English,...

    , though he is not buried there, contrary to what some biographies state.
  • A statue by Alfred Gilbert
    Alfred Gilbert
    Sir Alfred Gilbert was an English sculptor and goldsmith who enthusiastically experimented with metallurgical innovations...

    , stands in Manchester Town Hall
    Manchester Town Hall
    Manchester Town Hall is a Victorian-era, Neo-gothic municipal building in Manchester, England. The building functions as the ceremonial headquarters of Manchester City Council and houses a number of local government departments....

    , opposite that of Dalton.
  • There is a Wetherspoon's pub named after him in the centre of Sale

Further reading

  • Fox, R, "James Prescott Joule, 1818–1889", in .

External links