We have heard the fabulous story that young James Watt watched a water boil in a tea kettle, which rattled the kettle’s lid and struck James by the power of steam. This childhood experience, the story goes, inspired him to invent the steam engine as an adult. It is indeed a marvelous fable, ranking with Newton’s apple.
But why didn’t a Chinese James Watt invent the same steam engine, long before the English one? After all the Chinese have been boiling tea for a thousand years before England. Why not a Tamil boy or girl watching idli being steamed? Same water. Or someone in Sumeria or Egypt?
Predecessors
It turns out, even James Watt was not the first Englishman to work on a steam engine. The Royal Society of England records a Frenchman Denis Papin, who claimed to have run a steam powered boat on a French river, with recommendations from Gregory Leibniz and Christian Huygens. Some drawings of Papin survive, but nothing else. Some historians say that Isaac Newton, a fierce rival of Leibniz was then President of the Society, and ignored Papin because of his Leibniz connection. Curiously, neither Newton nor most scientists of the society, showed much interest in either Papin’s engine or even about heat as worthy of scientific study.
But in 1698, a patent was filed by an Englishman Thomas Savery, for a “fire-engine” – that is, a boiler of water heated by a coal-fired furnace. The steam produced pushed a metal piston up. This piston was attached to a lever, at whose other arm was suspended a bucket which was lowered into a coal mine. Coal mines often filled up with ground water, which prevented mining. When the bucket filled with water from the coal, the boiler was cooled by splashing cold water on it. This cooled the boiler and the steam, which condensed and the steam pressure, which had driven up the piston, fell. Atmospheric pressure then lowered the piston, and the connected lever pulled up the bucket full of water. Today we call this a pump – but since it was powered by heating water, the popular name was fire engine. Several Savery engines sold for around 150 to 200 pounds. This was the first effective steam engine : but since the actual work of lifting the water was done by atmospheric pressure rather than the steam, historians call Savery’s engine an “atmospheric engine.”
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| Newcomen's Steam engine: Pic from: Michael de Greasley's Youtube video |
Savery had a fourteen year patent, which was extended to 35
years, until 1733. A generation later, in 1712, Thomas Newcomen, another Englishman,
made some improvements to the Savery engine, paying a license fee to Savery’s
heirs. His Newcomen engine, was also an atmospheric engine, but it was safer,
could stand higher heat and steam pressure, and could pump up water from 150
feet rather than the thirty feet of Savery’s engine. So it was popular among
coal and other miners, who paid a royalty of about 450 pounds a year to operate
a Newcomen engine.
Mathematical
Instruments
James Watt, was born far north of the British island, in Scotland, in 1735 (after Savery’s patent had expired, and Newcomen engines became popular). He went to school, where he was taught mathematics and astronomy, which he loved more than Greek and Latin, which were also part of his education. When he turned eighteen, Watt traveled to London, to learn some skills as an apprentice. Carnegie says that it was a twelve day travel by walk or horse carriage; quite hazardous; and the whole village met in church to pray for such travelers’ welfare.
Watt joined John Morgan of Cornhill road, a maker of mathematical instruments. These were navigational instruments like the compass, the telescope, the quadrant, the geared watch; mercantile instruments like brass scales, rulers; surveying instruments like theodolites, etc. Watt was described as “having a fortune at his fingers’ ends”; that is mechanically very talented; and he was a quick learner. After a couple of years, he returned to Glasgow to set up a shop selling such devices. But he wasn’t very successful. He expanded to repairing musical instruments like fiddles and pianos, and fishing equipment and surveying tools.
Early experiments at
Glasgow
He had made friends with some academics at the University of Glasgow and was allowed to perform some experiments there. The university had a model version of a Newcomen engine, which had broken down, and even Watt’s efforts couldn't fix it. The model was sent to London for repair, but a curious Watt built a similar model himself, using a vial as a boiler and hollow canes as tubes. He observed that the engine wasted a lot of heat, alternately cooling and heating the cylinder. Experimenting a little more, he discovered Latent Heat.
Latent heat is the property of water, whereby when it reaches its boiling point, it doesn’t immediately turn to steam, but continues to absorb heat without any sensible (measurable) change in temperature. After absorbing this heat for a while some of the water turns into steam. The heated steam has much more thermal energy than water at the same temperature (five times, as Watt found out).
Excited, he met Professor Joseph Black of the university, and explained what he had discovered. An amused Black, showed Watt that he had discovered the same phenomenon a few years earlier. They gained a mutual respect for each other.
External Condenser
Believing Watt could improve the Newcomen engine, a local businessmen, John Roebuck formed a partnership, investing a thousand pounds for Watt’s research. The understanding was that, when Watt finally made a better engine, Roebuck would get two thirds of the revenue as the financier.
Watt’s first great insight was about the inefficiency of alternatively heating and cooling the cylinder, to get mechanical work out of it. In 1769, he added an external condenser to the engine, which received the piped off excess steam. This vastly increased the efficiency of the engine. Several mine owners bought this engine from Watt.
But, then Roebuck went bankrupt. And Watt stopped working further on improvements to the engine.
An Era of Canals
Watt spent several years working as a surveyor, putting his mathematical skills to use. He surveyed several canals, designed bridges, and docks and piers. He surveyed the Monkland, Clyde, Forth, Caledonian and Perth canals, receiving about ₤400 for the last of these. He designed a bridge over the river Clyde for which he was paid 37 pounds.
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| Horse drawn Boats |
It was the age of canals in England. Catching up to Europe, India, China and other countries which had developed intricate networks of canals over the centuries, England built several new canals for transport. One of the wettest countries in the world, it was blessed with several perennial rivers and streams. Connecting these with canals was quite profitable for landowners, especially owners of coal and iron mines. Transporting by water was far cheaper than transporting by muddy roads over uneven terrain. Horses walking alongside the canals could pull more loads on water than on land.
Matthew Boulton
Boulton was a maker of “toys” – by which was meant decorative cups and jars, plated jewellery, silver plates, candlesticks, buttons, buckles, mirrors – things sold by “fancy stores” in every street corner in India today. He had a manufactory at Soho, near Birmingham, an area rich in coal, which had developed an ironwork industry. The factory was mainly water powered.
In his times, France was considered superior to England at manufacturing these “toys”. Often, Boulton shipped good from his factory across the English channel and then had them return, pretending the goods were imported from France. This was an effective business tactic. He soon drew wealthy and reputable customers, including the best advertisers possible – the English royal family. When princes George (later king) and Edward bought swords from Boulton, his reputation, and business, soared. He even attracted the attention of Princess Catherine of Russia, who declared his products superior to those of France.
Reduced summer time water flows in the streams powering his mills, convinced Boulton to buy a Watt engine to pump water into a lake to supply his factory. After seeing Watt’s external condenser engine, Boulton realized not only could it renew his water supply, a better steam engine may replace it and power his factory. Cashing in on a debt that Roebuck owed him, Boulton took over from Roebuck as a business partner for Watt and persuaded him to move to Birmingham and work on improving the engine.
James Watt was lucky to get such a good and influential friend. He had great faith in Watt as an inventor and spoke in praise of him to whomever listened. Catherine of Russia listened, and agreed, and offered Watt five thousand pounds to move to Russia and continue his investigations. It took an alarmed Boulton all his persuasive powers to keep Watt in England.
Industrial Success
One major problem was the reliability of cylinder to operate under the higher pressure and heat of steam. An iron-master John Wilkinson, invented a boring machine, with which he made stronger cannons. Boulton introduced him to Watt, who began using Wilkinson’s cylinders for his steam engine. Wilkinson was not only a supplier, he was also one of the first customers of Watt’s engines, which he used for blowing machines, forge hammers and other metal works.
The first Watt engines were popular among mine owners, who cancelled orders for Newcomen engines. These engines were not manufactured, but assembled on location from assembled parts constructed on site under Watt’s personal supervision. Most of the parts and even the tools were handcrafted by smiths. Alcoholism, the lack of engineers, absenteeism were major problems for their business. Some others began copying the design without paying Watt a patent fee.
Boulton and Watt offered a business model, based on the far superior efficiency of the Watt engine over the Newcomen engine. Most of the money was saved on coal used to power the engine. The mine owners were charged one-third of the estimated savings on coal – for example, if a Watt engine used 400 tonnes of coal compared to an earlier Newcomen engine which used 1000 tonnes, the customers had to pay the cost of 200 tonnes (one third of the cost of 600 tonnes of coal they saved). This led to a lot of bargaining disputes and negotiations, all of which Watt was personally averse to. Fortunately, Boulton’s excellent business skills came into play.
Boulton got the patent extended for twenty years, from 1775 to 1800, by an act of Parliament. This ensured no other company could make or sell a steam engine with an external condenser. So inefficient Newcomen engines continued to be sold. This also prevented innovations and experiments with high pressure engines, which Watt detested as potentially deadly.
Boulton realized that the steam engine had a limited market as a pump, with only a linear action; if the pistons linear movement could be converted to a rotary motion, whole new industries would buy the engine. A competitor, Pickard, had developed a crank-shaft to do just that, but wanted to cross-license it with the external condenser. Watt refused. He instead invented a sun-and-planet gear, an alternative mechanism that turned linear into rotary motion, in 1781. He sold an engine with this rotary mechanism to Whitbread’s brewery, which replaced horses with Watt’s engines to grind corn. Boulton proposed that brewers pay for one-third of the horses that breweries replaced – if the Watt engine replaced eighteen horses, they received annual fees equivalent to the cost of maintaining six horses. This was also the beginning of the practice of rating engine power in number of horses : or horsepower.
Improvements
Meanwhile Watt worked on other improvements. In 1781, he also developed a double acting engine, where the steam operated on both ends of the cylinder. In 1782, he developed a compound engine, where two engines combined their power.
He also developed a steam pressure indicator, which measured and showed the pressure of the active steam, making the operation much safer. An ingenious invention, in 1788 was the centrifugal governor, (originally invented by Huygens), which regulated the rate of steam and rotary action, so that it would neither slow down nor speed up much, but maintain a somewhat constant speed. A steam throttle was useful in actually controlling the amount of steam flowing, and controlling the speed of the rotary engine.
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| Sun and Planet gear Pic: Wikipedia |
With these significant improvements, other industries also bought the Watt engine. The textile industry which had mechanised looms; the metal forging industry; and mills. Boulton himself employed them later in minting coins. Competitors and patent infringements and fighting over dues were a constant problem. Boulton and Watt lost a lot of potential revenue, but eventually became rich and reputed men, because of their machine.
Prime Mover
The steam engine is a prime mover, which replaced human, animal and water power in a vast number of industries, with. It changed the world in a way that perhaps no other invention before or after has done. The stationary atmospheric engine became a stationary steam engine, slowly expanding into new industries. Then it evolved into a more compact engine, capable of moving itself – a locomotive engine. Finally steam power was adapted to operate turbines.
It was quite gradual; it evolved over two centuries, before diesel petrol and electric engines began to replace steam engines as major prime movers in several industries.
Boulton conscious of its significance and impact, declared: “I sell, sir, what all men desire: power.”
James Watt, inventor
extraordinary
Watt was not just an practical mechanic and industrial
inventor; he had extraordinary scientific skills as witnessed by his independent
discovery of Latent Heat. Humphrey Davy said that Watt “was distinguished as a
natural philosopher and chemist; his inventions
demonstrate his profound knowledge of those sciences, and that peculiar
characteristic of genius, the union of
them for practical application."
Watt invented a copying machine which soaked an original document
or drawing in a chemical and could transfer it to another sheet of paper. He didn’t
sell many, but some of them were in use for over a hundred years. He improved
the gas lamp; invented an unfinished arithmetical machine; and even built a
sculpture copying machine.
Carnegie says Watt, continuing on extraordinary discoveries of Joseph Priestley and Antoine Lavoisier, discovered that water was a compound of flammable air and dephlogisiticated air – independently also discovered by Cavendish. But his name is strongly associated with the steam engine, all other discoveries pale in comparison.
Lunar Society
Boulton was not only a business partner for Watt. He was a personal friend and intellectual compatriot. When Watt lost his first wife, and contemplated marrying another lady, her family objected. Boulton wrote a recommendation letter to Watt’s prospective father-in-law lauding his friend’s virtues.
Boulton had met the ingenious American scientist Benjamin Franklin, the Scottish philosopher and economist Adam Smith, a medical doctor Erasmus Darwin (grandfather of Charles), the chemist and clergyman Joseph Priestley and businessman and potter Josiah Wedgwood. He brought them all together at his Birmingham mansion, on full moon nights, discussing science, inventions and discoveries. They called themselves the Lunar Society. They have been called the Founding Fathers of the Industrial Revolution.
Watt eventually died in 1819, a few years after Boulton. Neither of them saw the emergence of the railways, though Watt apparently once journeyed on a paddleboat powered by steam engine. The British magazine “Chemist” paid him a fitting tribute:
“Different from other public benefactors by never having made or pretended to make it his goal to benefit the public. This unpretending man conferred more benefit to the world, than all those who for centuries made it their special business to look after public welfare.”
There are statues to Watt in London, Manchester and Birmingham. The watt was adopted as a unit of power, in 1889, by the British Association for the advancement of Science. The Bank of England issued a ₤50 currency note with images of Watt and Boulton in 2009.
References
1. James Watt: A Biography, by Andew Carnegie
2. Creating the Twentieth Century, by Vaclav Smil
3. Industrial Revelations : Youtube series
4. The Lunar Society, by Jenny Uglow
5. Wikipedia
6. Other videos, internet
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