The Steam Engine: Tinkering vs. Science
How the Laws of Thermodynamics turned early steam engines into the power of the Industrial Revolution
The Motive Power of Fire:
An Exhaustive Historical Analysis of the Interplay Between Steam Engineering and the Laws of Thermodynamics
1. Introduction: The Paradox of the Prime Mover
The history of the steam engine stands as the most profound counter-narrative to the linear model of scientific progress. In the conventional understanding of technological development, theoretical science precedes applied engineering; the physicist discovers a law, and the engineer builds a machine to exploit it. The story of steam, however, inverts this progression. The steam engine—the leviathan that powered the Industrial Revolution, drained the mines of Cornwall, and reshaped the geopolitical landscape of the 19th century—was not born from the elegant equations of university professors. It was forged in the gritty, empirical fires of ironmongers, millwrights, and instrument makers who operated for over a century without a coherent theory of what “heat” actually was.
This report provides a comprehensive analysis of the relationship between the steam engine and the laws of thermodynamics, partitioned into two distinct eras: the Empirical Era (pre-1850) and the Thermodynamic Era (post-1850). We examine the “Henderson Thesis”—the assertion by Lawrence Joseph Henderson that “Science owes more to the steam engine than the steam engine owes to science” 1—testing its validity across different epochs of development.
The analysis reveals a complex, bidirectional lineage. In the 18th and early 19th centuries, the steam engine acted as a provocation to science. Its operation, particularly the generation of motive power from heat, presented a phenomenon that the prevailing “Caloric” theory of heat could explain only imperfectly. The engine’s brute reality forced the intellectual crisis that led Sadi Carnot, James Joule, Rudolf Clausius, and William Thomson (Lord Kelvin) to formulate the laws of thermodynamics. However, once those laws were codified in the mid-19th century, the relationship inverted. The later developments of the steam turbine, the triple-expansion engine, and the internal combustion engine were not the products of blind tinkering but the deliberate applications of the new science. Thus, while the engine birthed the science, the science ultimately matured the engine, guiding it toward the theoretical limits of efficiency that define modern power generation.
2. The Pre-History of Steam: The Science of Pneumatics and the Vacuum (1600–1700)
To understand the intellectual environment into which the steam engine was born, one must look not to the science of heat, but to the science of air. The 17th century was the age of the vacuum. The Scientific Revolution had produced a profound shift in the understanding of the atmosphere, driven by figures such as Evangelista Torricelli, Blaise Pascal, and Otto von Guericke.4
2.1 The Conceptual Foundation: Atmospheric Weight
Before 1600, the Aristotelian horror vacui (nature abhors a vacuum) dominated natural philosophy. By the mid-1600s, this was replaced by the understanding that the atmosphere possessed weight. Torricelli’s barometer demonstrated that the weight of the air could support a column of mercury. Von Guericke’s dramatic demonstration with the Magdeburg hemispheres showed that the force exerted by atmospheric pressure against a vacuum was immense—capable of resisting the pull of teams of horses.4
This “new science” of pneumatics provided the essential mechanism for the early steam engines. These machines were not, in the modern thermodynamic sense, “heat engines” utilizing the expansion of a hot gas. They were “atmospheric engines.” Heat was merely the agent used to displace air and create a vacuum; the actual work was performed by the crushing weight of the atmosphere. Thus, the earliest engines were firmly rooted in the scientific discoveries of the 17th century, contradicting the idea that they were purely unscientific inventions. As noted by historians, the steam engine was a “child of seventeenth-century science,” specifically the science of air pressure.4
2.2 The Precursors: Papin and Savery
The transition from scientific demonstration to industrial application began with Denis Papin and Thomas Savery. Papin, a French mathematician and assistant to Christiaan Huygens, experimented with steam cylinders in 1690. He observed that a piston could be raised by steam and then pulled down by the vacuum created upon cooling.5 While Papin’s work remained largely experimental, it established the piston-and-cylinder configuration that would later dominate the industry.
In 1698, Thomas Savery patented the “Miner’s Friend,” the first commercially sold steam-powered device.6 Savery’s machine was a pump, not a piston engine. It operated by admitting steam into a vessel to displace water, then condensing the steam to create a vacuum that sucked water up from the mine sump.
Scientific Context: Savery’s device relied directly on the known properties of condensation and vacuum.
Operational Failure: The machine was thermodynamically disastrous. High-pressure steam came into direct contact with the cold water being pumped, leading to massive condensation losses. Furthermore, the “vacuum lift” was limited by atmospheric pressure to about 30 feet, requiring a dangerous high-pressure “push” phase to raise water further.6
Savery’s engine demonstrated the potential of “fire” to raise water, but it also highlighted the desperate need for a mechanism that separated the steam from the water it was pumping. It was an invention caught between the science of the vacuum and the yet-to-be-born science of thermodynamics.
3. The Atmospheric Era: Newcomen and Empirical Optimization (1712–1760)
The true beginning of the steam age lies with Thomas Newcomen, an ironmonger from Dartmouth. In 1712, Newcomen erected an engine at the Conygree Coalworks that synthesized the piston concept of Papin with the vacuum generation of Savery, creating the “Atmospheric Engine.”
3.1 The Mechanism of the Atmospheric Engine
Newcomen’s engine differed fundamentally from Savery’s. It used a rocking beam. On one side, a heavy pump rod went down the mine shaft; on the other, a piston moved inside a cylinder.
The Power Stroke: Steam from a boiler filled the cylinder as the counterweight pulled the piston up.
The Vacuum: Cold water was injected directly into the cylinder, condensing the steam instantly.
The Work: The resulting vacuum allowed atmospheric pressure to push the piston down, lifting the pump rod on the other side.6
This machine was the first reliable “fire engine.” However, its operation was dictated by mechanics, not thermal physics. The cylinder was heated and cooled with every cycle—a thermodynamic absurdity that consumed enormous quantities of coal.
3.2 The “Science” of Newcomen
Was Newcomen a scientist? Historical evidence suggests he corresponded with Robert Hooke, the curator of experiments at the Royal Society. In a 1703 letter, Hooke specifically advised Newcomen to drive his piston “purely by means of vacuum,” warning against the dangers of high-pressure steam.8 This advice proved critical. Newcomen’s engine operated at atmospheric pressure, making it safe enough for widespread adoption despite the primitive metallurgy of the time.
However, beyond this pneumatic insight, the thermal design was purely empirical. Newcomen did not calculate the volume of steam required or the latent heat of condensation. He simply adjusted the valves until the machine worked. The efficiency of these early engines was abysmal—around 0.5%.9 They were viable only at coal mines where fuel was essentially free.
3.3 John Smeaton: The Pinnacle of Empiricism
By the mid-18th century, the Newcomen engine was a standard industrial tool, but it remained inefficient. Enter John Smeaton, the father of civil engineering. Smeaton’s work on the steam engine in the 1770s represents the apex of the empirical method, demonstrating how far technology could advance without a governing theory.10
Smeaton did not possess a theory of thermodynamics. Instead, he employed a rigorous methodology of parameter variation. He constructed an experimental model engine at his home in Austhorpe and systematically tested every variable:
The diameter of the cylinder.
The length of the stroke.
The size of the injection nozzle.
The loading of the piston.
The type of coal used.
Smeaton conducted over 130 distinct experiments, isolating one variable at a time while holding others constant—a remarkably modern scientific method applied to engineering.10 Through this exhaustive testing, Smeaton developed a set of “proportions” for engine building. He compiled tables that dictated exactly how large a boiler should be for a given cylinder size.
The Result: Smeaton doubled the “duty” (efficiency) of the Newcomen engine, raising it from roughly 5 million foot-pounds per bushel of coal to over 12 million.10
The Insight: Smeaton’s achievement proves that significant optimization is possible through observation and trial-and-error alone. He did not need to know why a certain nozzle size was better; he only needed to know that it was better. This era of engineering was characterized by the accumulation of practical constants rather than the derivation of physical laws.
4. James Watt and the Proto-Scientific Turn (1760–1800)
If Newcomen was the artisan and Smeaton the experimenter, James Watt was the “philosophical engineer.” His contributions mark the transition from pure empiricism to an approach informed by scientific concepts, though still lacking the comprehensive framework of thermodynamics.
4.1 The Repair of the Glasgow Model
In 1764, Watt was asked to repair a model Newcomen engine for the University of Glasgow. He found that the model, despite being mechanically perfect, could barely sustain operation. It consumed steam at a voracious rate. Watt realized that the small scale of the model exacerbated the heat loss; the cylinder walls were cooling down so rapidly that the incoming steam condensed before it could do any work.8
4.2 The Influence of Joseph Black and Latent Heat
Watt’s environment at Glasgow University placed him in the orbit of Dr. Joseph Black, the chemist who discovered latent heat. Black had demonstrated that converting water to steam required a massive input of heat that did not raise the temperature (the heat became “latent”).8
Watt’s Experiment: Watt independently verified this. He mixed steam with cold water and was astonished to find that a small amount of steam could heat a large volume of water to boiling. When he consulted Black, the professor explained his doctrine of latent heat.
The Insight: This scientific concept was the key. Watt realized that the Newcomen engine was throwing away the vast energy investment represented by the latent heat of the steam every time it cooled the cylinder to create a vacuum. He formulated the defining axiom of steam engineering: The cylinder must be kept as hot as the steam that enters it.8
4.3 The Separate Condenser
This insight led to the Separate Condenser (patented 1769). Watt reasoned that if the condensation took place in a separate vessel that was kept permanently cold, the main cylinder could remain permanently hot.
Mechanism: A valve opened to connect the cylinder to the vacuum chamber (condenser). The steam rushed into the void and condensed, creating the vacuum in the cylinder without cooling the walls.
Impact: This single innovation tripled the efficiency of the steam engine, raising the duty to over 25-30 million foot-pounds.11
Empirical Enhancements: While the condenser was a theoretical breakthrough, Watt’s success also relied on mechanical craftsmanship. He partnered with John Wilkinson, whose new cannon-boring machine could produce iron cylinders with unprecedented precision, preventing steam leakage.15 He also added a “steam jacket” (a layer of steam around the cylinder) and insulated the piston—practical measures to enforce his “hot cylinder” rule.15
4.4 The Watt Indicator: The Secret Science
Watt also developed the Indicator, a device that traced the pressure inside the cylinder against the piston’s position. This produced a “P-V Diagram,” a graphical representation of the engine’s cycle.16
The Secret: Watt and his partner Matthew Boulton kept the indicator a closely guarded trade secret. They used it to diagnose and tune their engines, ensuring they delivered the efficiency promised to customers (which determined their royalties).
The Missed Opportunity: The indicator diagram is essentially a graph of Work ($\int P dV$). Had Watt published this tool and the data it produced, the science of thermodynamics might have emerged fifty years earlier. Instead, it remained a proprietary tool of the workshop, delaying the theoretical understanding of heat engines.16
5. High Pressure and the Cornish Rebellion (1800–1840)
James Watt held a monopoly on steam engine design until his major patents expired in 1800. During his reign, he staunchly opposed the use of high-pressure steam (”strong steam”), considering it dangerous and unnecessary.18 This resistance created a stagnation in design that was only broken by a new generation of engineers who valued raw power over low-pressure safety.
5.1 Trevithick and the “Puffers”
Richard Trevithick in Cornwall and Oliver Evans in America pioneered the use of high-pressure steam (30-50 psi and above). Trevithick’s “Puffers” dispensed with the condenser entirely. They admitted high-pressure steam, let it expand, and then exhausted it directly into the atmosphere.19
Empirical Leap: Trevithick’s move was empirically driven. He wanted engines that were small and light enough to move themselves—the birth of the locomotive. A Watt engine, with its heavy vacuum beam and condenser, was too massive for transport.
Thermodynamic Significance: By relying on the expansive force of steam rather than the vacuum, Trevithick shifted the operational principle closer to the modern understanding of a heat engine. The work was done by the pressure gradient of the hot gas, not the weight of the atmosphere.
5.2 The Cornish Engine and Compounding
In Cornwall, where fuel costs were high (due to the lack of local coal mines), a culture of extreme efficiency developed. Engineers like Arthur Woolf introduced compounding—using the steam twice. High-pressure steam was expanded in a small cylinder, and then the exhaust (still possessing usable pressure) was expanded in a larger cylinder.10
McNaughting: This process was often applied retroactively to existing beam engines, a practice known as “McNaughting” (after William McNaught). A high-pressure cylinder was added to the beam, boosting power and efficiency without replacing the entire engine.21
Lean’s Engine Reporter: The Cornish engineers published their efficiency data in a monthly journal, Lean’s Engine Reporter. This competitive environment drove the “duty” of Cornish engines to astronomical heights (over 50 million foot-pounds), far surpassing Watt’s designs.10
The Scientific Void: Crucially, this progress occurred without a clear understanding of why high pressure and compounding worked. Engineers knew that expanding steam saved coal, but they lacked the concept of “internal energy” or “entropy” to explain the mechanism. They were optimizing a machine whose fundamental physics remained a mystery.
6. The Theoretical Crisis: Carnot’s Reflection (1824–1840)
By the 1820s, the steam engine was the prime mover of European industry, yet its theoretical basis was non-existent. Why did high pressure increase efficiency? Was there a limit to how much work a bushel of coal could do? These questions plagued Sadi Carnot, a young French military engineer.
6.1 Sadi Carnot’s Motivation
Carnot was motivated by a sense of national inferiority. He believed that Britain’s industrial and military dominance over France was due to its superior utilization of the steam engine.23 He sought to uncover the general laws that governed these machines, independent of their mechanical details.
6.2 Reflections on the Motive Power of Fire (1824)
Carnot’s treatise is the foundational text of thermodynamics. In it, he abstracted the steam engine into an ideal “heat engine.”
The Caloric Model: Carnot operated under the accepted “Caloric Theory” of the time, which viewed heat as an invisible, weightless fluid that could not be created or destroyed.
The Water Wheel Analogy: Carnot famously compared the steam engine to a water wheel. Just as water generates power by falling from a high level to a low level, caloric generates power by “falling” from a high temperature ($T_{hot}$) to a low temperature ($T_{cold}$). The quantity of caloric was conserved in the process.24
6.3 The Carnot Principles
Despite the flaw in his model (heat is not conserved), Carnot deduced the two fundamental truths that govern all heat engines:
Temperature Difference is Key: The motive power of heat is independent of the agents employed (steam, air, alcohol) and depends solely on the temperatures of the bodies between which the transfer of caloric is effected.25
The Cycle: For maximum efficiency, the engine must operate in a reversible cycle (the Carnot Cycle), where no heat is transferred across a finite temperature difference.
6.4 The Clapeyron Connection
Carnot’s work was largely ignored by the engineers of his time. It was too abstract. It was resurrected in 1834 by Émile Clapeyron, who translated Carnot’s verbal arguments into the graphical language of the indicator diagram (P-V graph).7 Clapeyron showed that the area of the closed cycle on the graph represented the work done. This was the bridge that eventually allowed physicists to see the connection between the engineer’s “duty” and the theorist’s “work.”
7. The Great Synthesis: Thermodynamics (1840–1860)
The resolution of the steam engine’s mystery required the collision of the French theoretical school (Carnot) with the British experimental school (Joule).
7.1 James Joule and the Consumption of Heat
In the 1840s, James Prescott Joule, a Manchester brewer, conducted a series of meticulous experiments. He used falling weights to drive a paddle wheel submerged in water, measuring the rise in temperature caused by the friction.
The Discovery: Joule proved that mechanical work could be converted into heat at a fixed rate (the Mechanical Equivalent of Heat).27
The Paradox: This contradicted Carnot. Carnot said heat was conserved (like water over a wheel). Joule said heat was generated by work, and conversely, work must consume heat. If heat is consumed, it cannot be a conserved fluid.
7.2 Lord Kelvin’s Dilemma
William Thomson (Lord Kelvin) was deeply troubled by this contradiction. In his 1849 paper, “An Account of Carnot’s Theory,” he acknowledged Joule’s results but refused to abandon Carnot’s brilliant deduction that efficiency depends on temperature difference.28 Kelvin asked the pivotal question: If heat is consumed to make work, what happens to the “fall” that Carnot described? Does the heat simply disappear?
7.3 Clausius and the Two Laws (1850)
The synthesis was achieved by Rudolf Clausius in 1850. He realized that both Joule and Carnot were partially right.
The First Law (Energy Conservation): Energy is conserved. Heat is a form of energy. In a steam engine, some heat is indeed converted into work and disappears as heat (validating Joule).
The Second Law (Entropy): Heat cannot spontaneously flow from cold to hot. For a heat engine to work, heat must flow from a hot source to a cold sink. Not all the heat can be converted to work; some must be rejected to the cold sink. This “rejected heat” corresponds to the “fall” Carnot observed.30
The Impact on the Steam Engine:
This was the moment the steam engine was understood. It was not a machine that used the “force of steam” or the “weight of the atmosphere.” It was a heat engine operating between two thermal reservoirs. Its efficiency was strictly limited by the difference between the boiler temperature and the condenser temperature ($1 - T_c/T_h$). No amount of mechanical tinkering could overcome this limit.
7.4 Tyndall and the Public Understanding
John Tyndall played a crucial role in disseminating these new ideas to the public and the engineering profession. In his influential book Heat: A Mode of Motion (1863), Tyndall used the steam engine as the primary example to explain the dynamical theory of heat.32 He explicitly linked the “work done” by the engine to the molecular motion of the steam, cementing the connection between the industrial machine and the new physics in the public consciousness.
8. The Scientific Era: Rational Design (1860–1910)
Post-1850, the relationship between science and technology inverted. The laws of thermodynamics began to dictate the design of engines.
8.1 Rankine’s Manual: The Engineer’s Bible
William John Macquorn Rankine, a professor at Glasgow, translated the abstract physics of Clausius and Kelvin into practical engineering tools. His Manual of the Steam Engine and Other Prime Movers (1859) was the first textbook to apply thermodynamic laws to machine design.34
The Rankine Cycle: Rankine developed a theoretical cycle that, unlike the Carnot cycle, accurately modeled the phase changes (water to steam to water) in a real engine.
Predictive Design: Rankine’s equations allowed engineers to calculate the density, pressure, and latent heat of steam at any temperature. Engineers could now design cylinders with precise dimensions calculated to handle the specific volume of expanding steam. They could predict the efficiency gains of superheating before building the boiler.
8.2 The Triple Expansion Engine: Thermodynamics in Steel
The Triple Expansion Engine (standardized in the 1880s) was a direct application of thermodynamic principles to solve the problem of “initial condensation”.36
The Problem: As pressures rose to 150+ psi to increase $T_{hot}$ (and thus efficiency), the temperature drop in a single cylinder became massive. This cooled the cylinder walls so much that incoming steam condensed instantly, wasting heat.
The Solution: Thermodynamics dictated splitting the temperature drop. By expanding steam in three stages (High, Intermediate, and Low pressure), the temperature variance in any single cylinder was minimized. This kept the metal closer to the steam temperature, reducing irreversible heat transfer.
Result: These engines achieved thermal efficiencies of 15-20%, powering the golden age of steam shipping.
8.3 The Willans Line and Scientific Testing
Engine testing transformed from “seeing if it runs” to rigorous thermodynamic auditing. The Willans Line, developed by Peter Willans in the 1880s, plotted total steam consumption against load.38 This linear relationship allowed engineers to identify the “constant” losses (friction, radiation) versus the variable thermodynamic losses. Engineers used T-s (Temperature-Entropy) diagrams to visualize the cycle and pinpoint exactly where energy was being lost to irreversibility.
8.4 The Corliss Engine
The Corliss Engine represented the mechanical perfection of the reciprocating engine. Its intricate valve gear allowed for a variable “cutoff” of steam. This meant the engine could admit steam for only a fraction of the stroke and let it expand for the rest.40
Thermodynamic Link: This utilized the internal energy of the steam to perform work, maximizing the area under the P-V curve. The Corliss engine was a mechanical realization of the thermodynamic ideal of adiabatic expansion.
9. The Ultimate Convergence: The Steam Turbine (1884–Present)
The steam turbine stands as the definitive refutation of the idea that “science owes more to the steam engine.” The turbine owes its existence entirely to thermodynamics.
9.1 Charles Parsons and the Velocity Problem
Invented by Charles Parsons in 1884, the turbine solved the problem of utilizing the kinetic energy of steam.42 High-pressure steam expanding to a vacuum moves at supersonic speeds (over 2,000 ft/s). A simple impulse wheel would need to rotate at mechanically impossible speeds to capture this energy efficiently.
9.2 Thermodynamic Design: Staging and Entropy
Parsons applied the laws of thermodynamics to design a machine that extracted energy in small increments.
Staging: He placed rows of stationary and rotating blades in series. Each stage allowed a small pressure drop, and thus a small (manageable) increase in velocity.
Entropy Calculations: The design of the blades required complex calculations of enthalpy and entropy. Parsons had to calculate the increasing volume of the steam as its pressure dropped, widening the turbine casing at the low-pressure end to accommodate the flow.44
Result: The turbine achieved continuous rotary motion with high efficiency (thermal efficiencies eventually reaching 30%+). It was a machine that could not have been invented by empirical tinkering; it required the mathematical modeling of fluid flow and heat transfer.
9.3 Debunking Perpetual Motion
Finally, thermodynamics served a critical “negative” function. In the late 19th century, the patent offices were flooded with designs for “Perpetual Motion” machines—devices that claimed to run on liquid air or zero-point energy without consuming fuel.46 The Laws of Thermodynamics provided the theoretical framework to reject these patents outright. Engineers stopped wasting resources on impossible machines and focused on pushing the asymptotic limits of the Rankine cycle.
10. Comparative Data and Analysis
10.1 The Trajectory of Efficiency
The evolution of the steam engine can be quantified by its “Duty” (efficiency). The following table illustrates the jump in performance following the integration of thermodynamic principles.
Era
Engine Type
Dominant Design Philosophy
Duty (Millions ft-lb/bushel)
Approx. Thermal Efficiency
Key Limitation
1712
Newcomen
Empirical / Pneumatic
4.3
0.5%
Heating/Cooling of Cylinder
1774
Watt
Proto-Scientific (Latent Heat)
12.5 - 20
1.5% - 2.5%
Low Pressure / Saturation
1840
Cornish (Woolf)
Empirical / High Pressure
60 - 80
6% - 9%
Material Strength / Danger
1890
Triple Expansion
Thermodynamic Application
150+
15% - 20%
Reciprocating Mass
1910
Steam Turbine
Thermodynamic Creation
--
25% - 35%
Metallurgical Limits (Creep)
Table constructed from synthesized data in.9
10.2 The Shift in Relationship
The analysis confirms a distinct phase shift.
Phase 1 (1700-1850): Tech $\rightarrow$ Science. The engine exists. Science struggles to explain it. The “caloric” theory is patched together to account for the engine’s behavior.
Phase 2 (1850-Present): Science $\rightarrow$ Tech. Thermodynamics exists. The engine is redesigned to conform to it. The turbine is created from first principles.
11. Conclusion
The relationship between the steam engine and the laws of thermodynamics is a story of reciprocal debt. Lawrence Henderson’s famous assertion that “Science owes more to the steam engine than the steam engine owes to science” is strictly true only for the genesis of the field. The roaring, coal-hungry engines of Newcomen and Watt provided the physical anomaly that shattered the static Newtonian worldview and forced the birth of energy physics. They were the catalysts for the intellectual revolutions of Carnot and Joule.
However, to apply Henderson’s maxim to the entire history of steam is a fallacy. Once the laws of thermodynamics were forged, they became the master of the machine. The later 19th century saw the steam engine tamed, refined, and ultimately transfigured into the steam turbine by the rigorous application of those very laws. The Triple Expansion engine and the Parsons turbine were not merely “improved” engines; they were physical manifestations of the Second Law of Thermodynamics.
In the final analysis, the steam engine gave science the concept of Energy, and in return, science gave the steam engine the gift of Efficiency. It was a trade that powered the modern world.
Works cited
What Came First: Thermodynamics or the Steam Engine? | by Kameron Sanzo, Ph.D., accessed November 21, 2025, https://medium.com/the-innovation/what-came-first-thermodynamics-or-the-steam-engine-c0cca0996b0b
Lawrence Joseph Henderson quote: Science owes more to the steam engine than the steam... - A-Z Quotes, accessed November 21, 2025, https://www.azquotes.com/quote/586648
‘Science’, how is it formed? - UNL Digital Commons, accessed November 21, 2025, https://digitalcommons.unl.edu/cgi/viewcontent.cgi?article=5619&context=libphilprac
Steam engine time | Logarithmic History - WordPress.com, accessed November 21, 2025, https://logarithmichistory.wordpress.com/2025/11/09/steam-engine-time-9/
History of the Watt Steam Engine - Science | HowStuffWorks, accessed November 21, 2025, https://science.howstuffworks.com/innovation/inventions/watt-steam-engine.htm
Steam Engine History - MSU College of Engineering, accessed November 21, 2025, https://www.egr.msu.edu/~lira/supp/steam/
A History of Thermodynamics: The Missing Manual - PMC - PubMed Central, accessed November 21, 2025, https://pmc.ncbi.nlm.nih.gov/articles/PMC7516509/
Science and steam - The Roots of Progress, accessed November 21, 2025, https://blog.rootsofprogress.org/science-and-steam
Steam engine - Wikipedia, accessed November 21, 2025, https://en.wikipedia.org/wiki/Steam_engine
The Making of Steam Power Technology - IRIS, accessed November 21, 2025, https://www.iris.sssup.it/bitstream/11382/303321/1/MakingFinal.pdf
Smeaton vs Watt: the race to improve the steam engine, accessed November 21, 2025, https://www.ice.org.uk/news-views-insights/inside-infrastructure/smeaton-vs-watt-race-to-improve-the-steam-engine
Mysterious Heat | The Engines of Our Ingenuity - University of Houston, accessed November 21, 2025, https://engines.egr.uh.edu/episode/1686
James Watt - Wikipedia, accessed November 21, 2025, https://en.wikipedia.org/wiki/James_Watt
The Most Useful Man Who Ever Lived - The New Atlantis, accessed November 21, 2025, https://www.thenewatlantis.com/publications/the-most-useful-man-who-ever-lived
Watt Steam Engine - World History Encyclopedia, accessed November 21, 2025, https://www.worldhistory.org/Watt_Steam_Engine/
Watt’s steam engine indicator | Science Museum Group Collection, accessed November 21, 2025, https://collection.sciencemuseumgroup.org.uk/objects/co51439/watts-steam-engine-indicator
Boulton and Watt | History of Western Civilization II - Lumen Learning, accessed November 21, 2025, https://courses.lumenlearning.com/suny-hccc-worldhistory2/chapter/boulton-and-watt/
Richard Trevithick: pressurized steam required courage of conviction, accessed November 21, 2025, https://robertthanlon.com/2024/04/22/richard-trevithick-pressurized-steam-required-courage-of-conviction/
Richard Trevithick - Wikipedia, accessed November 21, 2025, https://en.wikipedia.org/wiki/Richard_Trevithick
Patenting of the High-Pressure Steam Engine | Research Starters - EBSCO, accessed November 21, 2025, https://www.ebsco.com/research-starters/history/patenting-high-pressure-steam-engine
William McNaught (Glasgow) - Wikipedia, accessed November 21, 2025, https://en.wikipedia.org/wiki/William_McNaught_(Glasgow)
How the McNaught Compound Beam Engine Revolutionized Steam - YouTube, accessed November 21, 2025,
accessed November 21, 2025, https://en.wikipedia.org/wiki/Thermodynamics#:~:text=Historically%2C%20thermodynamics%20developed%20out%20of,France%20win%20the%20Napoleonic%20Wars.
Reflections on the Motive Power of Fire - Wikipedia, accessed November 21, 2025, https://en.wikipedia.org/wiki/Reflections_on_the_Motive_Power_of_Fire
REFLECTIONS ON THE MOTIVE POWER OF FIRE, AND ON MACHINES FITTED TO DEVELOP THAT POWER Sadi Car, accessed November 21, 2025, https://geosci.uchicago.edu/~moyer/GEOS24705/2009/Carnot_orig.pdf
Emile Clapeyron - EoHT.info, accessed November 21, 2025, https://www.eoht.info/page/%C3%89mile%20Clapeyron
How Did We Get Here? The Tangled History of the Second Law of Thermodynamics, accessed November 21, 2025, https://writings.stephenwolfram.com/2023/01/how-did-we-get-here-the-tangled-history-of-the-second-law-of-thermodynamics/
Lord Kelvin - Wikipedia, accessed November 21, 2025, https://en.wikipedia.org/wiki/Lord_Kelvin
An Account of Carnot’s Theory of the Motive Power of Heat, accessed November 21, 2025, https://www.eoht.info/page/An%20Account%20of%20Carnot%E2%80%99s%20Theory%20of%20the%20Motive%20Power%20of%20Heat
Clausius and the Second Law of Thermodynamics | Research Starters - EBSCO, accessed November 21, 2025, https://www.ebsco.com/research-starters/history/clausius-and-second-law-thermodynamics
Second law of thermodynamics - Wikipedia, accessed November 21, 2025, https://en.wikipedia.org/wiki/Second_law_of_thermodynamics
John Tyndall rescues Julius Mayer, 1862 | Skulls in the Stars, accessed November 21, 2025, https://skullsinthestars.com/2023/07/31/john-tyndall-rescues-julius-mayer-1862/
Darwin Online - Heat a mode of motion. by John Tyndall, LL.DFRS etc. Professor of Natural Philosophy in the, accessed November 21, 2025, https://darwin-online.org.uk/converted/pdf/1868_Tyndall_Heat_mode_motion_A6175.pdf
A manual of the steam engine and other prime movers : Rankine, William John Macquorn, 1820-1872 : Free Download, Borrow, and Streaming - Internet Archive, accessed November 21, 2025, https://archive.org/details/amanualsteameng03rankgoog
The Life and Legacy of William Rankine - Purdue e-Pubs, accessed November 21, 2025, https://docs.lib.purdue.edu/cgi/viewcontent.cgi?article=3086&context=iracc
How a Triple-Expansion Steam Engine Works #Shorts - YouTube, accessed November 21, 2025,
The Pursuit of Efficiency and the Science of Steam - Creatures of Thought, accessed November 21, 2025, https://technicshistory.com/2023/11/30/the-pursuit-of-efficiency-and-the-science-of-steam/
Willan’s Line: Actual Work Turbine | PDF | Watt | Power (Physics) - Scribd, accessed November 21, 2025, https://www.scribd.com/document/427562716/Steam-formula
Performance Modeling of New and Existing Steam Turbines - American Chemical Society, accessed November 21, 2025, https://pubs.acs.org/doi/pdf/10.1021/ie5032309
A General-Purpose Technology at Work: The Corliss Steam Engine in the Late-Nineteenth-Century United States | The Journal of Economic History, accessed November 21, 2025, https://www.cambridge.org/core/journals/journal-of-economic-history/article/generalpurpose-technology-at-work-the-corliss-steam-engine-in-the-latenineteenthcentury-united-states/105A54480CA78DC54D49D596061B5FE4
Study of the Engineering Design of a Single-Cylinder High-Pressure Steam Engine with a Corliss Valve Gear - MDPI, accessed November 21, 2025, https://www.mdpi.com/2076-3417/15/7/3587
Steam turbine - Wikipedia, accessed November 21, 2025, https://en.wikipedia.org/wiki/Steam_turbine
How turbines came to power the world - Drax UK, accessed November 21, 2025, https://www.drax.com/uk/power-generation/turbines-came-power-world/
The Optimisation of Steam Turbine Design - CORE, accessed November 21, 2025, https://core.ac.uk/download/pdf/153778037.pdf
Charles Parson - Steam Turbine Biography - Scribd, accessed November 21, 2025, https://www.scribd.com/document/52416807/PARSONS
The end of perpetual motion? - Mostre - Museo Galileo, accessed November 21, 2025, https://mostre.museogalileo.it/motoperpetuo/en/after-leonardo/the-end-of-perpetual-motion.html
Perpetual Motion Machines — Why They Don’t Work? | by Devansh Mittal | Intuitive Physics, accessed November 21, 2025, https://medium.com/intuitive-physics/perpetual-motion-machines-why-they-dont-work-1e192d2c0f62
Problem 1: History of efficiency of engines The early engine, accessed November 21, 2025, https://geosci.uchicago.edu/~moyer/GEOS24705/2016/Assignments/PS7.pdf