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.”
 |
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.
 |
| 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.
 |
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
Related Links
James Watt's Steam Engine - my lecture at Varahamihira Science Forum
Charles Parsons - Inventor of Steam Turbines
Inventors and Discoverers - my blogs
