James Watt
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| James Watt | |
|---|---|
 Portrait of James Watt (1736-1819) by Carl Frederik von Breda | |
| Born | 19 January 1736 Greenock, Renfrewshire, Scotland |
| Died | 25 August 1819 (aged 83)[1] Handsworth, Birmingham, England |
| Residence | Glasgow then Handsworth, Great Britain |
| Nationality | British |
| Ethnicity | Scottish |
| Fields | Inventor and Mechanical Engineer |
| Institutions | University of Glasgow Boulton and Watt |
| Known for | Improving the steam engine |
| Religious stance | Presbyterian |
James Watt FRS (19 January 1736 – 25 August 1819)[1] was a Scottish inventor and mechanical engineer whose improvements to the Newcomen steam engine were fundamental to the changes brought by the Industrial Revolution in both the Kingdom of Great Britain and the world.
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[edit] Biography
James Watt was born on 19 January 1736 in Greenock, Renfrewshire, a seaport on the Firth of Clyde. His father was a shipwright, ship owner and contractor, and served as the town's chief baillie, while his mother, Agnes Muirhead, came from a distinguished family and was well educated. Both were Presbyterians and strong Covenanters. Watt's grandfather, Thomas Watt, was a mathematics teacher and baillie to the Baron of Cartsburn. Watt did not attend school regularly; initially he was mostly schooled at home by his mother but later he attended Greenock grammar school.[2] He exhibited great manual dexterity and an aptitude for mathematics, although Latin and Greek failed to interest him, and he absorbed the legends and lore of the Scottish people.
When he was 18, his mother died and his father's health had begun to fail. Watt travelled to London to study instrument-making for a year, then returned to Scotland – to Glasgow – intent on setting up his own instrument-making business. However, because he had not served at least seven years as an apprentice, the Glasgow Guild of Hammermen (any artisans using hammers) blocked his application, despite there being no other mathematical instrument makers in Scotland.
Watt was saved from this impasse by three professors of the University of Glasgow, who offered him the opportunity to set up a small workshop within the university. It was established in 1758 and one of the professors, the physicist and chemist Joseph Black, became Watt's friend.
In 1764, Watt married his cousin Margaret Miller, with whom he had five children, two of whom lived to adulthood. She died in childbirth in 1772. In 1777 he married again, to Ann MacGregor, daughter of a Glasgow dye-maker, who survived him. She died in 1832.
Watt had a brother by the name of John. He was shipwrecked when James was 17.
[edit] First engines
Finally, in 1776, the first engines were installed and working in commercial enterprises. These first engines were used for pumps and produced only reciprocating motion to move the pump rods at the bottom of the shaft. Orders began to pour in and for the next five years Watt was very busy installing more engines, mostly in Cornwall for pumping water out of mines.
The field of application of the invention was greatly widened only after Boulton urged Watt to convert the reciprocating motion of the piston to produce rotational power for grinding, weaving and milling. Although a crank seemed the logical and obvious solution to the conversion Watt and Boulton were stymied by a patent for this, whose holder, James Pickard, and associates proposed to cross-license the external condenser. Watt adamantly opposed this and they circumvented the patent by their sun and planet gear in 1781.
Over the next six years, he made a number of other improvements and modifications to the steam engine. A double acting engine, in which the steam acted alternately on the two sides of the piston was one. He described methods for working the steam expansively. A compound engine, which connected two or more engines was described. Two more patents were granted for these in 1781 and 1782. Numerous other improvements that made for easier manufacture and installation were continually implemented. One of these included the use of the steam indicator which produced an informative plot of the pressure in the cylinder against its volume, which he kept as a trade secret. Another important invention, one of which Watt was most proud of, was the Parallel motion / three-bar linkage which was especially important in double-acting engines as it produced the straight line motion required for the cylinder rod and pump, from the connected rocking beam, whose end moves in a circular arc. This was patented in 1784. A throttle valve to control the power of the engine, and a centrifugal governor, patented in 1788,[3] to keep it from "running away" were very important. These improvements taken together produced an engine which was up to five times as efficient in its use of fuel as the Newcomen engine.
Because of the danger of exploding boilers and the ongoing issues with leaks, Watt was opposed from the first to the use of high pressure steam—all of his engines used steam at very low pressure.
In 1794 the partners established Boulton and Watt to exclusively manufacture steam engines, and this became a large enterprise. By 1824 it had produced 1164 steam engines having a total nominal horsepower of about 26,000.[4] Boulton proved to be an excellent businessman, and both men eventually made fortunes.
[edit] Method and personality
Watt was an enthusiastic inventor, with a fertile imagination that sometimes got in the way of finishing his works, because he could always see "just one more improvement". He was skilled with his hands, and was also able to perform systematic scientific measurements that could quantify the improvements he made and produce a greater understanding of the phenomenon he was working with.
Watt was a gentleman, greatly respected by other prominent men of the Industrial Revolution. He was an important member of the Lunar Society, and was a much sought after conversationalist and companion, always interested in expanding his horizons. He was a rather poor businessman, and especially hated bargaining and negotiating terms with those who sought to utilize the steam engine. Until he retired, he was always much concerned about his financial affairs, and was something of a worrier. His personal relationships with his friends and partners were always congenial and long-lasting.
[edit] Later years
Watt retired in 1800, the same year that his fundamental patent and partnership with Boulton expired. The famous partnership was transferred to the men's sons, Matthew Boulton and James Watt Jr. Longtime firm engineer William Murdoch was made a partner and the firm prospered.
Watt continued to invent other things before and during his semi-retirement. He invented a new method of measuring distances by telescope, a device for copying letters, improvements in the oil lamp, a steam mangle and a machine for copying sculptures. Within his home in Handsworth Heath, Staffordshire, Watt made use of a garret room as a workshop, and it was here that he worked on many of his inventions.
He and his second wife travelled to France and Germany, and he purchased an estate in Wales at Doldowlod House, one mile south of Llanwrthwl, which he much improved.
He died on 25 August 1819 at his home "Heathfield" in Handsworth, Birmingham, England at the age of 83. He was buried on 2 September.
The garret room workshop that Watt used in his retirement was left locked and untouched until 1853, when it was first viewed by his biographer J. P. Muirhead. Thereafter, it was occasionally visited, but left untouched, as a kind of shrine. A proposal to have it transferred to the Patent Office came to nothing. When the house was due to be demolished in 1924, the room and all its contents were presented to the Science Museum, where it was recreated in its entirety.[5] It remained on display for visitors for many years, but was walled-off when the gallery it was housed in closed. The workshop remains intact, and preserved, and there are plans for it to go on display again at some point in the near future.
[edit] Controversy
As with many major inventions, there is some dispute as to whether Watt was the original sole inventor of some of the numerous inventions he patented. There is no dispute, however, that he was the sole inventor of his most important invention, the separate condenser. It was his practice (from around the 1780s) to pre-empt others' ideas which were known to him by filing patents with the intention of securing credit for the invention for himself, and ensuring that no one else was able to practice it. As he states in a letter to Boulton of 17 August 1784:
- I have given such descriptions of engines for wheel carriages as I could do in the time and space I could allow myself; but it is very defective and can only serve to keep other people from similar patents.
Some argue that his prohibitions on his employee William Murdoch from working with high pressure steam on his steam road locomotive experiments delayed its development. Watt, with his partner Matthew Boulton, battled against rival engineers such as Jonathan Hornblower who tried to develop engines which did not fall foul of his patents.
Watt patented the application of the sun and planet gear to steam in 1781 and a steam locomotive in 1784, both of which have strong claims to have been invented by his employee, William Murdoch. Watt himself described the provenance of the invention of the sun and planet gear in a letter to Boulton from Watt dated 5 January 1782:
- I have tried a model of one of my old plans of rotative engines revived and executed by W. M[urdock] and which merits being included in the specification as a fifth method...
The patent was never contested by Murdoch, who remained an employee of Boulton and Watt for most of his life, and Boulton and Watt's firm continued to use the sun and planet gear in their rotative engines, even long after the patent for the crank expired in 1794.
Watt opposed the use of high-pressure steam, and many inventors such as Richard Trevithick pioneered such engines, although frequently running into patent infringement actions by Watt. Those more efficient steam engines would eventually displace Watt's engines, leading to another industrial revolution with the development of the steam locomotive.
[edit] Legacy
James Watt's improvements transformed the Newcomen engine, which had hardly changed for fifty years, and initiated changes in generating and applying power, which transformed the world of work, and were a key innovation of the Industrial Revolution. The importance of the invention can hardly be overstated—it gave us the modern world. A key feature of it was that it brought the engine out of the remote coal fields into factories where many mechanics, engineers, and even tinkerers were exposed to its virtues and limitations. It was a platform for generations of inventors to improve. It was clear to many that higher pressures produced in improved boilers would produce engines having even higher efficiency, and would lead to the revolution in transportation that was soon embodied in the locomotive and steamboat. It made possible the construction of new factories that, since they were not dependent on water power, could work the year round, and could be placed almost anywhere. Work was moved out of the cottages, resulting in economies of scale. Capital could work more efficiently, and manufacturing productivity greatly improved. It made possible the cascade of new sorts of machine tools that could be used to produce better machines, including that most remarkable of all of them, the Watt steam engine.
Of Watt, the English Novelist Aldous Huxley (1894-1963) wrote; "To us, the moment 8:17 A.M. means something - something very important, if it happens to be the starting time of our daily train. To our ancestors, such an odd eccentric instant was without significance - did not even exist. In inventing the locomotive, Watt and Stephenson were part inventors of time."
[edit] Honours
Watt was a fellow of the Royal Society of Edinburgh and the Royal Society of London. He was a member of the Batavian Society, and one of only eight Foreign Associates of the French Academy of Sciences.
The watt is named after James Watt for his contributions to the development of the steam engine, and was adopted by the Second Congress of the British Association for the Advancement of Science in 1889 and by the 11th General Conference on Weights and Measures in 1960 as the unit of power incorporated in the International System of Units (or "SI").
This SI unit is named after James Watt. As with every SI unit whose name is derived from the proper name of a person, the first letter of its symbol is uppercase (W). When an SI unit is spelled out in English, it should always begin with a lowercase letter (watt), except where any word would be capitalized, such as at the beginning of a sentence or in capitalized material such as a title. Note that "degree Celsius" conforms to this rule because the "d" is lowercase.—Based on The International System of Units, section 5.2.
[edit] Memorials
Watt was buried in the grounds of St. Mary's Church, Handsworth, in Birmingham. Later expansion of the church, over his grave, means that his tomb is now buried inside the church. A statue of him, Boulton and Murdoch is in Birmingham, as are five other statues of him alone, one in Chamberlain Square, the other outside the Law Courts. He is also remembered by the Moonstones and a school is named in his honour, both in Birmingham. An extensive archive of his papers is held at Birmingham Central Library. Matthew Boulton's home, Soho House, is now a museum, commemorating the work of both men. The University of Glasgow's Faculty of Engineering, the oldest in the United Kingdom, (where Watt was a professor) has its headquarters in the James Watt Building, which also houses the department of Mechanical Engineering and the department of Aerospace Engineering.
The location of James Watt's birth in Greenock is commemorated by a statue, close to his birthplace. Several locations and street names in Greenock recall him, most notably the Watt Memorial Library, which was begun in 1816 with Watt's donation of scientific books, and developed as part of the Watt Institution by his son (which ultimately became the James Watt College). Taken over by the local authority in 1974, the library now also houses the local history collection and archives of Inverclyde, and is dominated by a large seated statue in the vestibule. Watt is additionally commemorated by statuary in George Square, Glasgow and Princes Street, Edinburgh.
The James Watt College has expanded from its original location to include campuses in Kilwinning (North Ayrshire), Finnart Street and The Waterfront in Greenock, and the Sports campus in Largs. Heriot-Watt University near Edinburgh was at one time the School of Arts of Edinburgh, founded in 1821 as the world’s first Mechanics Institute, but to commemorate George Heriot, the 16th century financier to King James, and James Watt, after Royal Charter the name was changed to Heriot-Watt University. Dozens of university and college buildings (chiefly of science and technology) are named after him.
The huge painting James Watt contemplating the steam engine by James Eckford Lauder is now owned by the National Gallery of Scotland.
Watt was ranked first, tying with Edison, among 229 significant figures in the history of technology by Charles Murray's survey of historiometry presented in his book Human Accomplishments. Watt was ranked 22nd in Michael H. Hart's list of the most influential figures in history.
Over 50 roads or streets in the UK are named after him.
A colossal statue of Watt by Chantrey was placed in Westminster Abbey, and later was moved to St. Paul's Cathedral. On the cenotaph the inscription reads:
- NOT TO PERPETUATE A NAME,
- WHICH MUST ENDURE WHILE THE PEACEFUL ARTS FLOURISH,
- BUT TO SHOW
- THAT MANKIND HAVE LEARNED TO HONOUR THOSE
- WHO BEST DESERVE THEIR GRATITUDE,
- THE KING,
- HIS MINISTERS, AND MANY OF THE NOBLES
- AND COMMONERS OF THE REALM
- RAISED THIS MONUMENT TO
- JAMES WATT
- WHO DIRECTING THE FORCE OF AN ORIGINAL GENIUS
- EARLY EXERCISED IN PHILOSOPHIC RESEARCH
- TO THE IMPROVEMENT OF
- THE STEAM-ENGINE
- ENLARGED THE RESOURCES OF HIS COUNTRY
- INCREASED THE POWER OF MAN
- AND ROSE TO AN EMINENT PLACE
- AMONG THE MOST ILLUSTRIOUS FOLLOWERS OF SCIENCE
- AND THE REAL BENEFACTORS OF THE WORLD
- BORN AT GREENOCK MDCCXXXVI
- DIED AT HEATHFIELD IN STAFFORDSHIRE MDCCCXIX
A lecture theatre in the Mechanical & Manufacturing Engineering building at the University of Birmingham is named "G31 - The James Watt Lecture Theatre".
On 29 May 2009, the Bank of England announced that Watt would appear on a new £50 note, alongside Matthew Boulton.[6]
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