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James Watt and the Rise of Steam Professor John Marsh Head of School of Engineering
James Watt and the Rise of Steam
Professor John Marsh Head of School of Engineering
The School of Engineering at the University of Glasgow
The oldest university school of Engineering in the UK
The Regius Chair of Civil Engineering and Mechanics was
established at Glasgow by Queen Victoria in 1840.
The First Engineering Degree programme in the UK 1872
The School is located in the James Watt and Rankine Buildings –
both named after pioneering engineers
James Watt
19 Jan 1736 – Born in Greenock
1764 – married Margaret Miller (died 1773)
1777 – married Ann MacGregor
25 August 1819 – Died in Birmingham
1784: Fellow of the Royal Society of
Edinburgh
1785: Fellow of the Royal Society
1806: Honorary Degree of Doctor of Laws,
from the University of Glasgow
1814: Foreign Associate of the French
Academy
Background
Great Grandfather
– Covenanter killed at Bridge of Dee
– Family forced to leave Aberdeenshire
Grandfather – Thomas Watt
– Founded School of Mathematics in Greenock
– Led to the Parish School in Greenock 1696
Father – James Watt
– Shipwright/contractor/provider
– Famous for his skill in making instruments
Muirheads of Lachop – family that can
trace its history to before 1122
Mother – Agnes Muirhead
– Relative of George Muirhead, Professor of
Humanity at the University
As a child….
Too delicate to attend school regularly
Fascinated by geometry and steam
Considered backward at Greenock Grammar
School
– Not good at Latin or Greek
– Enthused by mathematics
Aged 15 – read The Mathematical Elements of
Natural Philosophy by Willem Jacob 's
Gravesande
– Chemical experiments
– Small electrical machine
Read books, books, books…
– And did so all his life
Aged 17
– James’ mother dies
– Father’s business virtually collapses
1753 - James Watt starts his career
Leaves his father’s workshop in Greenock and moves to Glasgow to
become a mathematical instrument maker
– Stays with his mother’s family in Glasgow
– Finds a job with an ‘optician’
– Difficult to develop his career because of the rules of the Incorporation of Hammermen
Develops links with the University of Glasgow through George Muirhead,
Professor of Humanity
– School friend Andrew whose father, John Anderson, would become Professor of
Natural Philosophy
– In 1754 Robert Dick, then the current Professor of Natural Philosophy, advises him to
go to London
1755-1756 in London
The Journey took 12 days on horseback
– But by 1900 the journey took 8 hours by steam locomotive
When he gets there, similar rules about trades apply
– 7 year apprenticeship
James Watt wants to complete training in one year
– John Morgan, mathematical instrument maker in Finch Lane, Cornhill, takes him on for a
fee of £20 (which James Watt borrows from his father)
Watt lived in considerable poverty
– To cost his father as little as possible, he lodged with his master
– The draughty workshop, poor food, long hours, and painstaking work made him ill
– Moreover, he kept off the streets as there was a danger of conscription into the army
Statues of Watt – what is he holding?
National Portrait Gallery, Edinburgh
George Square, Glasgow
Close look at the statue in the Hunterian Museum
Back in Glasgow
Incorporation of Hammermen still does not recognise his
qualifications
BUT the University is not subject to the same laws and
rules as the city
Robert Dick asks him to repair a new collection of
astronomical instruments, which had been presented to the
University by Alexander Macfarlane
The University then allocate him a small room as a
workshop - 20 foot square…
…then a room accessible to the public to use as an
instrument shop
He is now Mathematical Instrument Maker to the University
Dowhill observatory
Watt’s friends at the University
Adam Smith
Professor of Moral
Philosophy
Joseph Black
Professor of
Anatomy and
Chemistry
John Anderson
Professor of Natural
Philosophy
John Robison
Future Professor of
Natural Philosophy
at Edinburgh
James Watt’s Facebook
Watt’s friends at the University
Adam Smith
Professor of Moral
Philosophy
Joseph Black
Professor of
Anatomy and
Chemistry
John Anderson
Professor of Natural
Philosophy
John Robison
Future Professor of
Natural Philosophy
at Edinburgh
1761-1763 Anderson asks Watt to repair his model Newcomen engine
Watt takes up the challenge
Learns French and Italian so can read the latest references!
Engine brought back from London in 1763…
…Watt repairs it…
…but it still does not work well!
The model Newcomen engine
…and it’s still in the Hunterian Museum!
Watt rediscovers latent heat
Take water – thought at that time be an element
– Watt later proved otherwise
Water boils at 100 °C
Take 1 kg of water at 100 °C and add to 1 kg of water at 0 °C
We get?
Watt rediscovers latent heat
Take water – thought at that time be an element
– Watt later proved otherwise
Water boils at 100 °C
Take 1 kg of water at 100 °C and add to 1 kg of water at 0 °C
We get 2 kg of water at 50 °C
Latent heat
Water boils at 100 °C
The steam is also at 100 °C
Take 2 kg of steam at 100 °C and add to 10 kg of water at 0 °C
We get?
Latent heat
Water boils at 100 °C
The steam is also at 100 °C
Take 2 kg of steam at 100 °C and add to 10 kg of water at 0 °C
We get 12 kg of water at 100 °C
Thermodynamics
Joseph Black had discovered latent heat in 1761
– Reported at the University of Glasgow on 23 April, 1762
Watt discovered latent heat by himself by 1764
Watt also discovered the ‘heat’ in steam was independent of pressure
These discoveries alone would make Watt a famous scientist
But he invented the separate condenser…….
"I had gone to take a walk on a fine Sabbath
afternoon, early in 1765. I had entered the
green by the gate at the foot of Charlotte
Street and had passed the old washing-
house. I was thinking upon the engine at the
time, and had gone as far as the herd's
house, when the idea came into my mind that
as steam was an elastic body it would rush
into a vacuum, and if a communication were
made between the cylinder and an exhausted
vessel it would rush into it, and might be
there condensed without cooling the cylinder
. . . . I had not walked farther than the golf-house
when the whole thing was arranged in my
mind."
James Watt’s BIG invention –the separate condenser
Newcomen Watt
Watt made his invention on a Sunday
He had to wait Monday to test it – using a syringe
and a tin can
Other things going on:
– 1760 Moved his main business to the city
– 1764 Married Margaret Miller
– 1765 ‘My whole thoughts are but on this machine. I can
think of nothing else’
Watt made his invention on a Sunday
He had to wait Monday to test it – using a syringe
and a tin can
Other things going on:
– 1760 Moved his main business to the city
– 1764 Married Margaret Miller
– 1765 ‘My whole thoughts are but on this machine. I can
think of nothing else.’
Don’t marry an engineer!
Built a model in his cellar
– But it ‘snifted at many openings’
Built a larger model
– ‘Leaked in many directions’
The problem was the cylinder had to be hammered into shape rather than
bored
Watt had now spent all his spare money and took up work instead as a
surveyor
– Monklands Canal
– Forth and Clyde Canal
Partnership with Roebuck
Watt needed money to develop his
invention
He also needed the best technology
1765 - Introduced to John Roebuck, founder of
the Carron Iron Works in Falkirk, by Joseph
Black
1767 – Roebuck partnership
– Pays £1000 of Watt’s debts
– Supports the experiments
– Secures the patent
– Acquires ⅔ of the invention
Watt’s workshop at Kinneil House
1768 Builds larger model
– Disaster when mercury dissolves the solder
2 months later there is second trial
– Astonishing results – ‘success to my heart’s content’
BUT
Patent runs into difficulties
– Much of society does not approve of patents
– Finally granted 5 Jan 1769
Watt hates business
– ‘Would rather face a loaded cannon than settle a disputed account or
make a bargain’
Roebuck goes bankrupt
Sep 1769 – Monster engine built – a lot depends on it!
– Indifferent success
– A ‘clumsy job’
– Piston packing included cork, oiled rags, old hats, paper, and horse dung!
Roebuck himself now in financial difficulty
– His pits had flooded
– Watt’s new engine had failed
1770 Watt works as engineer on the canals
1773 Watt’s wife dies
1773 Roebuck is effectively bankrupt
1773 Watt owes Black £1000 to keep the patent going
Roebuck introduces Watt to Matthew Boulton Matthew Boulton
Enter Matthew Boulton
Boulton had craftsmen working together in a
‘manufactory’
– A radical new idea
Boulton’s factory is in Birmingham, now with
a ‘good road’ to London
– Well connected to other cities
Boulton saves Roebuck from bankruptcy by
buying the rights to the engine
Nov 1774
‘The business I am here about has turned out
rather successful;
that is to say, the fire engine I have invented is
now going, and answers much better than any
other that has yet been made.’
Success
1776 – The Bentley Mining Company installs a Boulton-Watt engine
Uses ¼ of the coal of a Newcomen engine
Cylinder crafted by the best ironmaster in Britain, John Wilkinson, who had
recently developed a technique for boring cylinders
The valves, piping, and fittings were manufactured at the Soho
Manufactory
– A factory 2 miles from Birmingham partnered by Boulton and Watt.
The new Boulton-Watt engine was a great success
– Watt & Boulton became very busy maintaining business at Cornwall mines and setting
up new pumps for the mines in the Cornwall region
BUT Summerlee Museum has a Newcomen engine from a coal mine
installed in 1810! – Why did the mine not use a Watt engine?
Summerlee Museum –Newcomen engine from 1810
Watt’s friends in Birmingham –The Lunar Society
Joseph PriestlyWilliam Withering William Small
Erasmus Darwin
Benjamin FranklinJosiah Wedgewood
Matthew Boulton
Soho House in Handsworth, Birmingham
James Kier
Beyond mines…
Boulton recognized the potential of the device for doing much more than
pumping water
– In June 1781 he wrote to Watt:
– "The people in London, Manchester and Birmingham are steam mill mad.
– …There is no other Cornwall to be found, and the most likely line for the consumption of
our engines is the application of them to mills which is certainly an extensive field"
By 1800, 84 British cotton mills used Boulton and Watt engines. So did
wool mills and flour mills!
The Horsepower and the Watt
In 1782 a sawmill ordered an engine that was to replace 12 horses
– Watt used data to determine that a horse could lift 33,000 pounds the distance of one
foot in one minute – and thus developed the units of horsepower (hp)
Watt's contributions are recognised every day
– The British (and American Engineering) unit for power, hp
– The SI unit for power, the Watt.
Watt’s other inventions
1781 - A method to convert reciprocating motion of the piston to rotating
motion
– The sun and planet gear system
– Better than a crankshaft (already patented, an idea Watt said was stolen from him)
1782 - The steam cylinder used valves above and below the piston
– The piston performed work on both the upward and downward stroke! This evened out
the stroking of the piston, performing equal work on each movement
The "parallel motion" device
– He said this was the invention of which he was most proud
The steam throttling valve and the mechanism to connect the throttle to
the engine governor
– Used together, these devices regulated steam flow into the piston and kept a constant
engine speed
The copying machine…..
1800 – Watt’s retirement
The workshop was in the attic
of Watt's home, Heathfield,
outside Birmingham
Watt spent a lot of time in the
workshop after his retirement
in 1800, partly to escape his
second wife
Main project was copying
sculpture, for which he
developed the two large copy-
mills which dominate the
workshop space
100 years later
The technology of steam continued to advance
Piston rings made it possible to use high pressure steam
By 1905 the estimated horsepower of steam engines was 150,000,000
horsepower
This is equivalent to the power of 3.6 billion male adults
– Around 10 times the number of male adults in the world of working age in 1905
– All working in full time manual labour
Beyond Watt –high pressure steam
The world’s fastest steam engine
Where is the separate condenser?
On 3 July 1938, the A4
class locomotive Mallard
raced down Stoke Bank at
126 mph to set a new
steam locomotive world
speed record
That record still stands
Beyond Watt –electricity from coal
The Rankine
cycle
Beyond Watt –electricity from oil
The Rankine
cycle
Beyond Watt –nuclear electricity
The Rankine
cycle
Beyond Watt –electricity from gas
The Rankine
cycle
Conclusion
Watt’s main invention is almost 250 years old – 1765
Watt died in 1819 – almost 200 years ago
BUT
Steam still generates at least 80% of the UK’s electricity
Around 40% of the UK’s electricity is even generated from coal!
Watt’s legacy benefits us every day
