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"I Sell Here, Sir, What All The World Desires To Have — Power"

This is the version of this talk prepared for the ASME North Texas Section Meeting, UT Arlington, Texas,
7:00 PM, February 18, 1999

by John H. Lienhard
Mechanical Engineering Department
University of Houston
Houston, TX 77204-4792
jhl [at] (jhl[at]uh[dot]edu)

Matthew Boulton uttered his remarkable double entendre to Johnson's biographer, Boswell, when Boswell visited the Boulton-Watt works in 1776:

I sell here, Sir, what all the world desires to have — POWER.

That says a lot about English thinking on the eve of the Industrial Revolution. For power (in both senses) was being transformed in England.


And what we learn from that period is that we engineers are primary agents of change — in any society. The late 18th century was a time when engineers embraced that role. It was a time when engineers walked in and assumed responsibility for turning the world upside down.


Boulton and Watt began making engines long after Thomas Savery made his first steam pump in 1698. The 18th-century steam work-horse was neither Savery's nor Watt's engine. It was the engine Thomas Newcomen built in 1711. Newcomen's engine had a power takeoff device so you could apply it to different jobs. When Watt filed his first engine patent in 1769, almost 600 Newcomen engines had been built. They'd been draining mines and replacing other labor for a long time.

But Watt's external condenser patent immediately doubled steam-engine efficiency. By 1784, Watt's engines were four times more efficient than the old Newcomen engines were. The first Watt engines put out only about 6 horsepower. But, in less than 20 years, he'd built engines that delivered as much as 190 horsepower.

The old Newcomen engines were huge, with cylinders two to ten feet in diameter. They formed two-story structures. Watt's engines still had cylinders 1½ to 5 feet in diameter, and, good as they were, they were by no means the basis of English production by 1800. Only 2000 English steam engines had been made by then, and fewer than 500 of them were new Watt engines. During the 18th century most power still came from water wheels and windmills.

But two things were happening: Steam was picking up those specialized tasks that were absolutely essential for the Industrial Revolution to take place — like pumping water out of mines. And steam was positioning itself to power the really heavy industries that would so change 19th-century life.

By 1800, the total installed capacity of all steam engines ever built was about the same as one of our big stationary diesel engines today. Most of the English countryside was still the bucolic world that Oliver Goldsmith wrote about.

By 1827, 58 years after Watt's patent, the Reverend Dionysius Lardner took stock of things in his handbook, The STEAM ENGINE Familiarly Explained and Illustrated. He includes everything from steam-engine history to rules for railway investors. Let me read some Lardner to you:

In a [recent] report it was announced that a steam engine ... in Cornwall, had raised 125 millions of pounds, 1 foot high, with a bushel of coals. ... The great pyramid of Egypt [weighs 13 billion] lbs. To construct it cost the labour of 100,000 men for 20 years. [Today it could] be raised ... by the combustion of 479 tons of coals.

The enormous consumption of coals in the arts and manufactures, and in steam navigation, has excited the fears of ... exhaustion of our mines. These apprehensions, however, may be allayed by the assurance [of] the highest mining and geological authorities, that the coal fields of Northumberland and Durham alone are sufficient to supply [us] for 1700 years, and ... the great coal basin of South Wales will ... supply the same demand for 2000 years longer.

Those reserves do little today to satisfy England's energy needs. But Lardner isn't done yet. He goes on:

... in speculations like these, the ... progress of improvement and discovery ought not to be overlooked. ... Philosophy already directs her finger at sources of inexhaustible power. ... We are on the eve of mechanical discoveries still greater than any which have yet appeared.

Lardner certainly underestimated our appetites. But, I suppose, he was right in perceiving the terrifying fact that human ingenuity will do more than we dare dream to keep meeting our frivolous wants as well as our real needs.

The energy crisis that Lardner shrugged off so easily in 1827 had been acute back in 1698. Miners had taken the coal out, all the way down to the water table. Without effective power sources to drive bailing pumps, they were stuck.

Thomas Savery pointed the way with his awkward steam pump in 1698. It looked like two huge wine flasks, side by side. You alternately filled each one with high pressure steam, driving water out and up a delivery pipe. Then you condensed the steam, sucking water up from a sump below. And you repeated the process.

The aristocrat Savery called his machine the "Miner's Friend," but it was a treacherous friend. Those great flasks were made of soldered copper held together with steel bands. That was no technology for holding steam at 100 pounds per square inch. The flasks sometimes blew up.

Then a Devon blacksmith, Thomas Newcomen, worked the kinks out of a new steam power system in 1711. He built a large cylinder with a piston in it, filled the cylinder with steam at atmospheric pressure, then squirted in cold water. The steam condensed, formed a vacuum, and sucked the piston downward in its working stroke.

Unlike Savery, he didn't need a not-yet-existent pressure-containment technology. Newcomen finally gave us effective practical means for getting at those huge inaccessible reserves of coal — those reserves that so filled Lardner with confidence a century later.

By the late 1700s, the huge walking-beam Cornish Pump version of Newcomen's engine was all over the mining regions of southwest England. Around 1800, Erasmus Darwin (doctor, poet, and friend of James Watt) wrote about one:

Press'd by the ponderous air the Piston falls
Resistless, sliding through its iron walls;
Quick moves the Balanced beam, of giant-birth,
Wields his large limbs, and nodding shakes the earth.

The Cornish Pump, simple and robust, followed mining into the American West. An old photo from the 1890s shows one in Tombstone, Arizona, with its great iron beam, three stories high, driving a rod down into the earth, powering stage after stage of pumps hundreds of feet below. Only a century ago, it was emptying tons of water a minute. But that machine was a technology from before 1769. It was frozen in time.

And so the new steam engines eclipsed wind and water power. European theoreticians had written the theory of the water turbine, but that theory didn't yield fruit until the 1820s and '30s, when France finally gave us the modern power-producing water-turbine.

But that was France as she began to get her feet under her again. From the 1780s until 
Napoleon went down at Waterloo, France had put almost 30 years of its energy into strife. Revolution, then war, had cost her dearly. Her roads, bridges, and merchant navy were in shambles. She'd done little to keep abreast of the English Industrial Revolution. Her economy was stagnant. Now, as the smoke cleared, the extent of thedamage also became clear.

So meet a young French naval engineer, Charles Dupin, who saw a chance to do his country and his career some good. He decided to go to England to study her secrets. There was little new in that. France had been spying on England even before the Industrial Revolution. In 1786, one French observer had remarked that English workers were,

haughty, quarrelsome, risk takers ... easy to suborn. When a new machine produces gain ... the French government can always be master of it in six months for a small outlay.

Of course, thinking like that had condemned France to a tag-along role in the first place. Now she had no choice. If France was to start over, she would have to begin in England.

Charles Dupin was upper crust, with typical French training in math and physics. He'd learned almost nothing of practical use. He was hardly kin to the "quarrelsome risk takers" who'd built English industrial greatness. But he wasn't stupid.

In 1816, Dupin set out on his first information-gathering raid into England. You catch a young man's arrogance in his reports. He sneers at the English when he can. But you also see a powerful gift for observation. He tells of steam-dredges and harbor works. He writes about new processes. Most important, he sees the breakdown of class separation. He sees England educating her working class.

In the end, Dupin returned to France to claim the political advantage he'd gained by his visits. But now, as a member of the Chamber of Deputies, he didn't forget what he'd learned. Dupin became a champion of practical education. He set up free schooling for workers. He fought tirelessly for industrial reform. He became an important agent for France's industrial recovery in the 19th century.

Another young French aristocrat was also trying to bring France into the 19th century. He was François Arago. Born on the eve of the French Revolution, Arago trained at the École Polytechnique — Napoleon's great academic think tank. When he was only 23, the École made him a professor of mathematics. He did basic work in optics and electricity. He helped to prove that light moves in waves. He measured the speed of sound in ice. He worked on the polarization of light. His electrical work anticipated Faraday.

But Arago looked beyond all that science toward its use. His work on electricity found use in telegraph systems. He took part in the study of steam-boiler explosions.

In his mid-40s he took up politics. His verve and charisma won liberal causes, like abolishing slavery in French colonies and improving conditions for sailors. Then, in 1834, Arago rose to address the French Academy of Sciences. He was about to take on another radical cause. This lecture was one the French Academy was not ready for. It was about James Watt.

He began by recalling two French thinkers who had the idea of a steam engine. But, he said, it took the English to put flesh and blood on that idea. They'd built the actual engines, and the only science that helped them was the science of their own shrewd observations. And, he added, those engines improved the life of the poor.

With that he'd gone too far. French intellectuals preferred to see English machines as barbaric. Arago faced an angry outcry. Soon after, he wrote a second paper to defend himself. He titled it, "On Machinery Considered in Relation to the Prosperity of the Working Classes." It says things most of us take for granted: Machines don't steal jobs, they create them. Machines make goods affordable to the poor. And so on.

Arago celebrated the humanitarian impulse that drove people like Watt in the first place. Watt really had created machines in the interests of the common people, of whom he was one.

Now, notice how I've drifted from the mechanical power side of Boswell's double entendre into the political power side. The two are certainly related.

And if means for large-scale power production was one thing that grew out of the 18th century, means for controlling power was another. Perhaps the most dramatic 
element on Watt's engine was his flyball governor.

Watt's governor was a superb example of feedback control. Feedback controllers, mechanisms that sense a discrepancy and correct it, are absolutely shot through our world today. We go through hardly an hour of any day without using feedback devices — float valves in our toilets, thermostats in our rooms, pressure-control valves and carburetion electronics in our cars.

This remarkable and ubiquitous part of our life was nonexistent in 1700. Yet feedback had made its first appearance 2000 years earlier in Hellenistic North Africa — in that stunning age of invention and experimentation.

Euclid and Archimedes worked in Alexandria. So did engineers like Philon, Ktsebios, and Heron. Those engineers were artists who worked for wealthy patrons. Their work was intellectual play. They used it to dazzle and entertain.

For example, we go to a banquet in, say, 100 BC. A bowl of wine sits on a center table with a spigot above it. We guests dip wine from the bowl. As the level drops, wine magically begins flowing from the spigot to refill the bowl.

Inside, hidden from view, is a ball-and-cock float-valve, just like the one in your 
toilet. It's pure feedback control. It senses, compares, and corrects the liquid level — by itself, without human intervention.

That sort of thing was common in the Hellenistic world. One of the first feedback devices was the water-clock flow regulator. The 3rd-century BC engineer Ktsebios made the ancient water-clock into an accurate timekeeper by inventing a float stopper to regulate a constant flow of water into the indicator tank.

Now consider something about feedback — about the self-regulation of machines: When we let go of the knob, we relinquish control. For the totalitarian mind that's a very uncomfortable thing to do.

Imperial Rome took over Egypt just before the birth of Christ. The Romans were great users of technology. But they didn't contribute many new ideas. And they certainly did nothing more with the feedback concept. Arab scholars and artisans kept the water-clock alive, but they also ignored the feedback concept that regulated it. For 1300 years the water-clock was the only vestige of the feedback concept in a totalitarian world. And in all that time, neither the Romans, nor the Arabs, nor anyone else invented one new feedback device.

With the feedback-controlled water clock squarely in front of them — with scholars reading and copying Hellenistic literature — with all the access in the world to this wonderful idea — no new feedback device came into being for the better part of two millennia. We could've made all sorts of devices with available technology — flow control, thermal regulation, windmill orientation, and so on and on. These things were within our grasp. Why didn't we do anything with them?

Well, authoritarian minds really do have trouble with feedback. It's antithetical to someone who wants to write rules and see them obeyed. Feedback had come into being in a golden age of intellectual freedom. By 1300, the water-clock was all that remained of that inventive outpouring.

Then, a new invention, with a whole new character, replaced it. The mechanical clock had no feedback features whatsoever. Its accuracy depended entirely on getting everything absolutely right at the start.

The orderly mechanical clock diverted the medieval imagination. Clockwork, with its wheels and gears, became the new metaphor for God's creation. God had ordered the planets just like clockwork, they said. He wound them up and set them in motion.

So the last vestige of self-regulation evaporated. We embraced the concept of clockwork, and by the year 1700 we'd stretched that concept to its limit.

Isaac Newton, who wrote down the physics of planetary motions, still thought that minor disturbances by, say, meteorites would destabilize planetary orbits. He didn't catch on to the fact that orbits are stable. He believed that God — the heavenly clockmaker — had to intervene from time to time to readjust His machine.

The French kings — the Louises — didn't reflect that view just in their fetish for elaborate clocks and clockwork toys. Their mercantile economic system reflected a clock-like concept of economic control.

The mercantile idea was that nations stipulate trade balances ahead of time. The nation is assumed to have colonies to provide raw materials and gold. A working class manufactures goods within the country. Those goods are then used by the aristocracy, and they're sold back to the colonies. The wants of the working class are to be minimized and its population increased.

That formula was calculated to drive over-regulated populaces into revolution. In England, revolution took the form of a growing realization that technology could free the working classes. English tradesmen saw that the people who made goods could own those goods. That violated the clockwork mercantile equation. And, sure enough, it's in this gathering revolution that feedback suddenly welled up again.

The revolution began among dissident Protestant English tradesmen. First they built a network of canals. Then they began producing and moving goods about, far from London and away from central government control. Their revolution was quiet and thorough. Commoners laid hold of invention. After the blacksmith Newcomen invented the steam engine, the game began in earnest.

You and I are surprised when we find industrial giants like Josiah Wedgwood, Matthew Boulton, and James Watt meeting with scientists like Erasmus Darwin, Joseph Priestly, and William Herschel. They formed a revolutionary cell-group called the Lunar Society. They talked about science, technology, and social issues. Joseph Bronowski said of the Lunar society,

What ran through it was a simple faith:
The good life is more than material decency, 
but the good life must be based on material decency.

And so the feedback control concept first returned to engineering in England. Float valves began turning up around 1740. They first appeared as water-level controllers in the new steam boilers and were soon followed by flush toilets with level controllers in their supply tanks.

Feedback played counterpoint to the brewing Industrial Revolution. It rode in on new claims to freedom. And our journey finally brings us to Scotland, where David Hume, James Watt, and Adam Smith were all heavily exploiting feedback; and their lives were interwoven.

Watt's flyball governor, invented in 1789, was the first modern controller. It was pure feedback in a very sophisticated form. The power demands on any engine vary as users want more or less power. Reduce the load without changing the steam supply, and the engine speeds up until it's going too fast to use steam efficiently.

Watt solved that by spinning the governor with a belt from the flywheel. When the flywheel sped up, so did the governor. The inertia of the flyballs swung the arms outward, and that drove a mechanism which closed down the steam supply valve. It was a combination of form and function that was pure poetry in motion. It was feedback in its purest form.

But Scotland's most famous feedback process was even more startling than the flyball governor. David Hume applied the feedback idea in a remarkable, and completely new, way in 1752. Hume laid out a theory of self-regulation of the international money market. He said that if a nation's price levels are lower than its neighbors', its exports rise. That brings in more money, but it also causes price levels to rise. Then the export of goods drops, and so on. That was a pure feedback description of the economy.

It was Hume's friend Adam Smith who really developed that thinking a few years later with his feedback laissez faire economic model. Of course, laissez fairetranslates to something like: "Let nature take its course," or "Let things manage themselves."

Smith published his definitive challenge to mercantilism, his Wealth of Nations, in 1776. It was very radical thinking. It was not only pure feedback. It was pure revolution as well.

But Smith's ideas now entered a world ready to think in these terms again. So the legacy of those ancient Hellenistic engineers finally bore its fruit after 1800 years. The feedback concept was right at the heart of 18th-century revolution. The Alexandrian concept of self-correction is what democracy is all about.

The language of the idea is shot through the American Constitution, which was developed right at the same time as Watt's engine. The "checks and balances" that we prize so highly are the control valves of a constitutional system. They are one more example of pure feedback control.

We took power away from princes and other leaders. We gave power over to a feedback controller — to our Constitution. We set up the machinery by which we could regulate ourselves.

Today we're surrounded by feedback controllers. We wonder how we ever could've thought differently! Yet we did. You and I are surprised that Newton saw God routinely interrupting the execution of His own laws to keep His creation running. But 18th-century Rationalists saw God not only as a clock-maker. They saw Him as the Great Clock-Winder as well. To understand that, we must understand the extent to which our technology mirrors our world view. It defines what we are.

The mechanical clock was powerfully expressive of our cultural center of gravity for a long time. Today, the idea of the control valve is far more deeply subsumed into our language and into our being than most of us realize.

Our technology — of which our art and our machinery are both part — our technology flows from some point deep within us. It is more powerful than kings and emperors. Ruskin said that

Great nations write their biographies in three manuscripts, the book of their deeds, the book of their words, and the book of their art — and of the three, the only trustworthy one is the last.

So we try to read the book of 18th-century art and technology. The people who ultimately create a civilization aren't its leaders and its warriors. Civilizations are made by people who actually have their hands on the machines that ultimately define civilization.

Matthew Boulton did far more than make a witty remark when he told Boswell that he sold "here, Sir, what all the world desires to have — POWER." He really was returning political power to the people when he sold them those great chuffing Watt engines.

Now I've told this story this evening to remind you of the enormity of the work that you students are studying to take up. Don't think for a minute that you work only on the backdrop of your culture. Far from it! You really will define the world for everyone else. And you'd better do it right! 


Lienhard, J. H., "I Sell Here, Sir, What All the World Desires to Have — POWER."Energy Laboratory Newsletter, No. 31, Houston TX: University of Houston Energy Lab., 1994, pp. 3-9.

Kanefsky, J., and Robey, J., Steam Engines in 18th-Century Britain: A Quantitative Assessment. Technology and Culture, Vol. 21, No. 2, 1980, pp. 161-186.

Lardner, the Rev. Dionysius, The Steam Engine Familiarly Explained and Illustrated. Philadelphia: Carey and Hart, 1836.

Hahn, R., Arago, Dominique François Jean. Dictionary of Scientific Biography, Vol. 1 (C.C. Gilespie, ed.) Chas. Scribner's Sons, 1970-1980.

Arago, M., Life of James Watt. 2nd ed., Edinburgh: Adam & Charles Black, 1839. (M. must stand for Monsieur. Arago's initials were D. F. J. This volume also includes Arago's rejoinder, "On Machinery Considered ...," Lord Jeffrey's Elogium of James Watt from the Encyclopaedia Britannica, and Lord Brougham's "Historical Account of the Composition of Water."

In 1905, the American visionary Andrew Carnegie also wrote a biography of James Watt. (Carnegie, A., James Watt, New York: Doubleday, Page & Co., 1905.) He made several references to Arago's important lecture.

Bradley, M. and Perrin, F., Charles Dupin's Study Visits to the British Isles.Technology and Culture, Vol. 32, No. 1, Jan. 1991, pp. 47-68.

Young, Otis E., Jr., Black Powder and Hand Steel: Miners and Machines on the Old Western Frontier. Norman, OK: Univ. of Oklahoma Press, 1975 (for the 1890 photo of a Cornish Engine.)

Mayr, O., The Origins of Feedback Control. Cambridge, MA: MIT Press, 1970.