Beer keg experiment (small)Papin engine (new) 3
Left: German engineer Otto Guericke's assistants pulling (doing work on) on a suction device in attempts to make a vacuum in a beer keg (c.1649); a pioneering experiment, which can loosely mark the start of the science of thermodynamics;
the Papin engine, conceived by French physicist Denis Papin in 1690; a direct precipitate of Guericke’s vacuum work, and the eventual model for the modern steam engine, and thus the Carnot cycle, upon which the science of thermodynamics is derived.
In pioneers, thermodynamics pioneers are those (100+) engineers, physicists, chemists, scientists, researchers, writers, and thinkers who over the years contributed to the background knowledge, formation and founding of the science of thermodynamics.

“The fascination of a growing science lies in the work of the pioneers at the very borderland of the unknown, but to reach this frontier one must pass over well traveled roads; of these one of the safest and surest is the broad highway of thermodynamics.” (Gilbert Lewis and Merle Randall, Thermodynamics, 1923)

Each person's photo-size is indicative of a combination of contribution density, impact, deepness of thought, theory penetration, and the enduring impact of their work. Ranks of pioneers within a given year are listed in descending order. Small quick-mark clickable icons, as described in (add), are used to facilitate topics and theories associated with the work of each person.

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The following is a chronological listing of individuals who pioneered the subject of thermodynamics:


Parmenides 75Parmenides (510-450BC)
Greek physicist-philosopher
485BC Initiated the famous “nature abhors a vacuum” debate in his essay On Nature, wherein he argued that a void or rather vacuum, in nature, cannot exist; a postulate that indirectly resulted in the invention or development of a number of things: atomic theory (c. 450BC), barometer (1643), vacuum pump (1650), piston and cylinder (1650), air pump (1657), steam engine (1690), gas laws (1645-1897), and eventually the science of thermodynamics (1865).

Aristotle 75 Aristotle (384-322BC)
Greek philosopher
(IQ icon=190)
350BC Introduced the “four element theory”, that the universe consists of four elements: earth, water, air, fire, of descending mass or density, respectively; denser elements tend to rise; lighter elements fall; earth is the heaviest element; fire the lightest; quote: “for any two portions of fire, small or great, will exhibit the same ratio of solid to void; but the upward movement of the greater is quicker than that of the less”; his Metaphysics presents one of the first uses of the term enérgeia (energy) to mean act or ‘activity’, ‘actuality’, or in a literal sense ‘(a state of) functioning’, deriving from energos "active, working," from en- "at" + ergon "work"; was the first to document the Mpemba effect, which he attempted to explain using a theory called 'antiperstasis'.

Geber 75 Geber (c.721-c.815)
Arabian chemist
790 Introduced the “three principles theory”, which states that metals are formed of two elements: sulphur, "the stone which burns", which is the principle of combustibility, and mercury, the principle of metallic properties; and salt is what gives solidity.

Paracelsus 75 Paracelsus (1493-1541)
Swiss chemist and physician
1524He adopted Aristotle’s four element theory, but reasoned that they appeared in bodies as Geber’s three principles; saw these principles as fundamental, and justified them by recourse to the description of how wood burns in fire. Mercury included the cohesive principle, so that when it left in smoke the wood fell apart. Smoke represented the volatility (the mercury principle), the heat-giving flames represented flammability (sulphur), and the remnant ash represented solidity (salt).

Galileo Galileo Galilei (1564-1642)
Italian physicist and astronomer
(IQ icon=180-200)
1592 Constructed an "an instrument for measuring heat" (thermometer), using expansion and contraction of air in a bulb to move water in an attached tube; in 1630, explained the “Pump problem”, namely Giovanni Baliani’s inquiry about the explanation of why a siphon, led over a hill about twenty-one meters high, failed to work, responded that it was the power of a vacuum which held the water up, and at a certain height (in this case, thirty-four feet) the amount of water simply became too much and the force could not hold any more, like a cord that can only withstand so much weight hanging from it; his with his 1632 Dialogue Concerning the Two Chief World Systems, is said to have initiated the science of invention of dynamics; in 1643, he encouraged his pupil Evangelista Torricelli to investigate the subject of the pump problem, after which Torricelli made the first barometer or "Torricelli vacuum".

Person icon 75Giovanni Baliani (1582-1666)
Italian mathematician, physicist, and astronomer
1630 His famous query letter to Galileo Galilei as to why an experiment he had made in which a siphon, led over a hill about twenty-one meters high, failed to work, launched the famous investigations into the pump problem; in circa 1635, he showed that by placing an iron pot filled with water on a spinning metal disk it was possible to make water boil—an experiment said to have been one of the first references to an experimental determination of the equivalence between heat and work.

Evangelista Torricelli 75 Evangelista Torricelli (1608-1647)
Italian mathematical physicist
1643 Investigated the pump problem, at the behest of his mentor Galileo Galilei, during which time he inverted a tube of mercury into a mercury dish, noticed the vacuum to have formed, noticed how the vacuum size varied from day to day, and hence invented the world’s first (mercury) barometer thus proving that atmospheric pressure exists.

Otto Guericke 75 Otto Guericke (1602-1686)
German engineer and physicist
c.1648 Being fascinated with the nature of cold, he began to devoted a considerable portion of his spare time to experimentation; and the question of the existence of a vacuum: “Could empty space exist, and is heavenly space unbounded?”; researching this query, brought into contact with Gaspar Schott, an adherent to Aristotle’s version of the denial of the void, and ultimately and to Rene Descartes’ adherence to the “denial of the vacuum” dictum; this puzzle intrigued Guericke and he went to work trying to evacuate the air form a well-caulked beer keg, which introduced him to the sealing problem, i.e. how to make a container air tight; after solving the sealing problem, he was said to have discovered the phenomenon of the compressibility of air; all of this resulted and led into the building, invention, and demonstration of a number of fundamental vacuum and vacuum engine principles: piston and cylinder, vacuum pump, vacuum bulb, Magdeburg hemispheres (1657), the calculation that a force of 2,700 pounds would be needed to pull the hemispheres apart, as is depicted in his 1672 lifting experiment.

Person icon 75Gaspar Schott (1608-1666)
German mathematical physicist
c.1652 A close associate of Otto Guericke; his 1657 book Mechanics of Gas Hydraulics detailed and diagrammed (Schott diagrams) Guericke’s experimental work on beer keg evacuations, vacuums, vacuum bulbs, vacuum pumps, the Magdeburg hemispheres, etc.; his publication, acted as a sort of liaison between the work of Guericke and Christiaan Huygens and Robert Boyle, who after reading his book began to make their own vacuum-based instruments, Boyle directing the construction of the pneumatical engine (air pump and vacuum pump), built in 1658 by his employee Robert Hooke, and Huygens, working with Denis Papin, making some of the first working gunpowder engines, wherein the explosion would act to create the vacuum.

Robert Boyle

Robert Hooke

Christiaan Huygens 75Christiaan Huygens (1629-1695)

Johann Becher 75 Johann Becher (1635-1682)
German chemist
1669Introduced the terra pinguis theory of combustion.

Denis Papin 75Denis Papin (1647-1712)
French physicist and engineer
1679In vented the Papin digester (1679) and Papin engine (1690).

Person icon 75Wilhelm Homberg (1652-1715)
Dutch chemist
1702 In a series of Essais de Chimie (1702-1709) he sought to rehabilitate the doctrine of the five principles, by separating them out in actual analysis with the burning glass, in a manner compatible with corpuscular philosophy; his “fire analysis” burning glass method conceptualized pure fire as a tangible, corpuscular substance that mad up other bodies and participated in chemical actions; his work ushered in the long-standing conception of fire as the universal solvent that resolved bodies into their ultimate constituents.

Georg Stahl 75 Georg Stahl (1659-1734)
German chemist and physician
1703 In modification of his mentor Johann Becher’s 1669 terra pinguis theory of combustion, introduced the phlogiston theory of heat, wherein heat was viewed as as being comprised of small particles with mass termed "phlogiston"; explained natural phenomena by affirming that “heat matter” (phlogiston) was contained in all combustible bodies and was made to appear when such bodies were burned.

Person icon 75Louis Lemery (1677-1743)
French physician and chemist
1709His “Conjectures and Reflections on the Matter of Fire and on the Light” in which, building on the previous burning glass experimental work and matter of heat (igneous particle) theories of Dutch chemist Wilhelm Homberg (1652-1715), he reconceptualized the “particles of fire” view in the form of a universal solvent for calcination and combustion processes by drawing an explicit analogy with the action of water as a solvent in regards to salts.

Johann Bernoulli 75Johann Bernoulli (1667-1748)c.1717

Jacob Bernoulli 75Jacob Bernoulli (1654–1705) c.1717

Herman Boerhaave 75 Herman Boerhaave (1668-1738)
Dutch physician and chemist
1724 His textbook Elements of Chemistry (aka Treatise on Fire), influenced by the earlier work of Louis Lemery’s corpuscular theory of fire, advocated what came to be known as "Boerhaave's law", which states that: “ever body, whether solid or fluid, is augmented in all its dimensions by any increase of its sensible heat”; was an associate of Polish physicist Daniel Fahrenheit; said to have introducing quantitative methods into the measure of temperature and mass and for carryed out some of the first calorimetric research.

Daniel Bernoulli 75 Daniel Bernoulli (1700–1782)
Dutch mathematician, physicist, and physician

Euler 75Leonhard Euler (1707-1783)
Swiss mathematician
(IQ icon=180-200)
c.1750Student of Johann Bernoulli (1667-1748); the eponym of (mathematician behind) the “reciprocity relation”, the mathematical substantiation behind entropy (S) defined as a state function (dQ/T) variable of heat (dQ); also behind the homogenous function, which supposedly is the mathematical form which relates an extensive property of a system to its component variables.

Joseph Black (75px) Joseph Black (1728-1799)
Scottish physician, physicist, and chemist
c.1757 Began a friendship with James Watt, the two supposedly conducting experiments with heat and steam; in 1761, noted that the temperature of a pail of ice-cold water placed in a warm room rose quite quickly, whereas, if the pail contained ice, the temperature remained constant for many hours while the ice melted, and thus discovered “latent heat”; was one of the first chemists to adopt Antoine Lavoisier’s caloric theories and taught them as early as 1784; his circa 1786 Lectures on Chemistry, introduced the first statements of the zeroth law.

Watt 75 James Watt (1736-1819)
Scottish instrument maker and engineer
(IQ icon=165)
c.1757 Supposedly, began conducting experiments on steam with Joseph Black and would go on to make a number of inventions and design improvements to the functionality of the steam engine, including: separate condenser (1765), sun and planet gear (1781), the fly-ball governor (1788), the indicator (1796) and "indicator diagram", made with his employee John Southern, which tracked the changes in volume of the piston, the definition of "pony power" (or horse power), all embodied in what came to be known as the Watt engine.

Lavoisier 75 Antoine Lavoisier (1743-1794)
French chemist
(IQ icon=170)

Benjamin Thomson (75px) Benjamin Thomson (1753-1814)
American-born English physicist
1787 Reacted to George Fordyce’s circa 1785 experiments which claimed to have measured a gain in the weight of water after it was frozen, by repeating Fordyce’s experiment to see for himself if this was in fact the case; his 1798 cannon-boring experiments, provided data for the first calculation of the mechanical equivalent of heat, which laid question to Lavoisier's caloric theory, as discussed in his famous “An Inquiry Concerning the Source of Heat which is Excited by Friction”; promoted Thomas Young to Royal Institute lecturer, and it was in these lecturers (1807) that Young, using Thompson's cannon-boring data, that the the first modern definition of heat and also of energy is found.

Humphry Davy 75 Humphry Davy (1778-1829)
British chemist and physicist
(IQ icon=185)
1799 His famous ice-rubbing experiments showed that ice cubes rubbed together in a room colder than the freezing point of water can be made to melt, a result which conflicted with the caloric theory.

Charles Desormes (1771-1862)
French physicist and chemist

Nicholas Clement (1779–1842)
French physicist and chemist

Carnot 100Sadi Carnot (1796-1832)
French engineer and physicist
c.1818 In circa 1818, he fell into the association of brother-in-laws Nicholas Clement and Charles Desormes, who did joint research on the physics of steam engines; all three, were said to have felt a need to boost France’s mills and factories industry operations, and that the way to do this was to better understand the principles behind the operation of steam engines; Carnot devoted the years 1820 to 1824 to this effort, the result of which was the self-published 1824 treatise Reflections on the Motive Power of Fire and on Machines Fitted to Develop that Power, a short booklet on the generalized theory of heat engines, out of which sprang a number of foundational physical models, namely: Carnot engine, Carnot cycle, and Carnot's principle, the latter of which being precursor to the second law.

Joseph Fourier 75Joseph Fourier (1768-1830)
French mathematical physicist
1822 His Analytical Theory of Heat, used Newton's law of cooling, namely, that the flow of heat between two adjacent molecules (or bodies) is proportional to the extremely small difference of their temperatures, to outlined a mathematical model of heat movement in various directions; he argued that any function of a variable, whether continuous or discontinuous, can be expanded in a series of sines of multiples of the variable.

Clapeyron 75Émile Clapeyron (1799-1864)
French physicist
1834 His “Memoir on the Motive Power of Fire” (a) brought Carnot’s Reflections into public light, (b) rewrote the Reflections using a graphical footing, by explaining the work output of the Carnot cycle using indicator diagrams, and (c) used a cleaner more accurate and rigorous mathematical style.

James Forbes (1809-1868)
Scottish physicist

Philip Kelland (1808-1879)
English mathematician

Joule 75 James Joule (1818-1889)
English engineer and physicist

John Nichol 75John Nichol (1804-1859)
Scottish astronomer

William Thomson 100William Thomson (1824-1907)
Irish-born Scottish physicist and mathematician

Robert Mayer 75Robert Mayer (1814-1878)
German physician and physicist

Lewis Gordon (1815-1876)
Scottish civil engineering

James Thomson 75James Thomson (1822-1892)
Scottish engineer

Rankine (75px)William Rankine (1820-1872)
Scottish mathematical physicist and engineer

Helmholtz 100 newHermann Helmholtz (1821-1894)
German physicist and physician
1843 His “On the Conservation of Force” presented one of the first versions of the conservation of energy; his 1882 paper "The Thermodynamics of Chemical Processes", one of the founding papers of chemical thermodynamics, showed, through derivation, how the long-sought chemical "affinity" (the force of reaction) of chemistry was measured by the "free energy" of the system, i.e. that which could be converted into other forms of usable energy (such as mechanical work or electricity), not by the heat of the reaction, hence disproving the thermal theory of affinity as was being advocated independently by Julius Thomsen (1854) and Marcellin Berthelot (1864)

Henri Regnault 75Henri Regnault (1810-1878)
French chemist and physicist
1845 During the years 1845-46, as the chair of chemistry at the École Polytechnique, he conducted research on the thermal properties of gases; during which time he mentored William Thomson; his 1847 “Experimental Relations … to determine the Main Laws and Numerical Data Entering into the Calculations of Steam Machines”, presented the results of a large number of specific heat measurements, date of which was used by Rudolf Clausius to confirm agreement between the mechanical equivalent of heat results of Robert Mayer and James Joule; his paper also stimulated William Rankine to develop his theories of thermo-dynamics and his “molecular vortex” hypothesis.

Maxwell 75James Maxwell (1831-1879)
Scottish mathematician and physicist
(IQ icon=200+)
1846 At age 15, became friends with William Thomson, the newly appointed (age 22) Glasgow professor of natural philosophy, and together with Peter Tait, whom he had been friends with since age 10 (1841), the three formed a post card connected circle of friends (Edinburg school), discussing with each other the subject of what they mutually referred to as “θ∆ics” (Maxwell’s coining) or thermo-dynamics (Thompson’s 1854 coining); from 1855 to 1878, published at least 47 documents (letters, articles, books, correspondence, etc.) on thermodynamics; in 1859, after reading Rudolf Clausius’ "On the Nature of the Movement, Which we call Heat" (1857) he formulated the famous "Maxwell distribution" of molecular velocities; in an 1867 letter to Tait, he proposed the now-famous Maxwell's demon; his 1871 Theory of Heat was one of the first simplified treatises on thermodynamics; his 1873 super-famous A Treatise on Electricity and Magnetism introduced what have come to be known as Maxwell equations, the four governing equations on the phenomenon of the interrelationship of electricity and magnetism, which he showed implicitly required the existence of electromagnetic waves traveling at the speed of light; was the first to recognize and promote the work of Willard Gibbs (1873-1876+); in 1874, using Gibbs' graphical thermodynamics papers, he constructed the first 3D thermodynamics surface model of the states of existence of water-like substance; in 1878-79, in his last year, his review article "Paradoxical Philosophy" and followup last poem "A Paradoxical Ode", outlined his views on: (a) the notion of the paradoxical philosopher and (b) his cryptic last thoughts the implications of the findings of electromagnetic theory, thermodynamics, and conservation of energy in regards religion, immortality, the soul, the life/death demarcation, evolution, morality, consciousness, down to the atomic level.

Peter Tait 75 Peter Tait (1831-1901)
Scottish mathematical physicist
1846In 1841, he became best friends with James Maxwell; in 1846, he entered into the thermodynamics communication network (Edinburg school) of Maxwell and William Thomson; in 1864, he wrote “Dynamical Theory of Heat” and “Energy”, which formed the basis of his followup 1868 A Sketch of Thermodynamics, a history of thermodynamics booklet, so to speak; in 1867, he and Thomson published Treatise on Natural Philosophy, a seminal energy-based physics textbook; his 1875 The Unseen Universe: or Physical Speculations on a Future State, written with Balfour Stewart, speculates on immortality, supposedly in an energy-thermodynamic sense, the heat death of the universe; how thoughts are molecular motions of the brain; how the universe may contain "bonds of energy" that connect to the thinking aspects of the mind; among other curious subjects.

Rudolf Clausius 100Rudolf Clausius (1822-1888)
German physicist
1850 His "On the Moving Force of Heat and the Laws which may be Deduced Therefrom", which resulted following him becoming “acquainted with [Carnot’s Reflections on the Motive Power of Fire (1824)] through the work of Clapeyron and Thomson”, the first in a collected works total of 16 papers: 1-9 (1850-65) on thermodynamics, 10-13 (1852-57) on the theory of electricity, and 14-16 (1857-62) are on gas theory (kinetic theory of heat), of which the first nine memoirs would form 1865 proto-textbook The Mechanical Theory of Heat (and followup 1875 second edition re-written textbook), initiated what would eventually become the state function, exact differential definition of the differential quantity of heat known as “entropy”, the first law, and the second law, which together define the subject of thermodynamics as known currently.

Julius Thomsen 75 Julius Thomsen (1826-1909)
Danish chemist

Marcellin Berthelot 75 Marcellin Berthelot (1827-1907)
French chemist

Horstmann 75August Horstmann (1842-1929) German physical chemistc.1865 Began studying the works of Clausius for applications in the calculation of equilibriums in chemical systems; his 1869 paper “Vapor Pressure and Heated Evaporation of Ammonium Chloride” was the first publication to apply entropy to chemical problems; in 1873, announced the condition for chemical equilibrium to be that of maximum entropy.

Ludwig Boltzmann (1872) 100Ludwig Boltzmann (1844-1906)
Austrian physicist

Balfour Stewart 75 Balfour Stewart (1828-1887)
Scottish physicist

Person icon 75Francois Massieu (1832-1896)
French engineer
1869 His “On the Various Functions Characteristic of Fluids and on the Theory of Vapors”, cited by Gibbs, introduced the idea of the "characteristic function", symbol Ψ (psi), of a fluid body, or Massieu functions, as they have come to be known; in Gibbs’ own summary words: “Massieu has shown how all the properties of a fluid ‘which are considered in thermodynamics’ may be deduced from a single function, which he calls a characteristic function of the fluid considered; he introduces two different functions of this kind, vis, a function of the temperature and volume, which he denotes by Ψ, and a function of the temperature and pressure, which he denotes by Ψ’; in both cases he considers a constant quantity (one kilogram) of the fluid, which is regarded as invariable in composition.”

Willard Gibbs 100Willard Gibbs (1839-1903)
American engineer and mathematical physicist

Planck 75 Max Planck (1858-1947)
German physicist
1877 At age 19, went to Berlin for a year of study with physicists Hermann Helmholtz and Gustav Kirchhoff and the mathematician Karl Weierstrass; he soon became close friends with Helmholtz; while there he undertook a program of mostly self-study of Rudolf Clausius’ writings, which led him to choose heat theory as his field; in 1879 completed his PhD dissertation, with a thesis “On the Second Fundamental Theorem of the Mechanical Theory of Heat”; in 1893, published his Outline of General Thermochemistry, a summary of the results of his electrochemical and thermochemical investigations, some of which overlapped with the work of Walther Nernst; investigations which trace to earlier 1889-90 papers of Planck published on the electromotive force; he expanded on and retitled this as the now-famous 1897 Lectures on Thermodynamics; in 1900, theorized that the internal energy of a black body (resonator) could be divided into a discrete number of “energy elements”, thus launching the quantum revolution; would go on to do work in radiation thermodynamics.

Gilbert Lewis 100 Gilbert Lewis (1875-1946)
American physical chemist

Person icon 75Merle Randall (1888-1950)
American physical chemist

Ralph Fowler 75 Ralph Fowler (1889-1944)
English physicist

Edward Guggenheim 75Edward Guggenheim (1901–1970)
English physical chemist

Emile Borel 75 Emile Borel (1871-1956)
French mathematician
1913 His “Statistical Mechanics and Irreversibility”, followed by his 1914 book Chance, introduced the typing monkeys explanation of the statistical view of the second law.

Eddington 75 Arthur Eddington (1882-1944)
English mathematician, astronomer, and physicist

Szilard 75 Leo Szilard (1889-1964)
Hungarian-born American physicist

Shannon 75 Claude Shannon (1916-2001)
American electrical engineer and mathematician

Landsberg 75 Peter Landsberg (1922-2010)
English physicist and statistical thermodynamicist

Peter Atkins 75 Peter Atkins (1984)
English physical chemist

See also
HT pioneers
Thermodynamics founders
Thermodynamicists (generations)
History of thermodynamics
Thermodynamicists (other)
Schools of thermodynamics
Founders of thermodynamics and suicide

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