The watt ( /ˈwɒt/ WOT; symbol: W) is a derived unit of power in the International System of Units (SI), named after the Scottish engineer James Watt (1736–1819). The unit, defined as one joule per second, measures the rate of energy conversion or transfer.

Definition[link]

• One watt is the rate at which work is done when an object's velocity is held constant at one meter per second against constant opposing force of one newton.

Failed to parse (Missing texvc executable; please see math/README to configure.): \mathrm{W = \frac{J}{s} = \frac{N\cdot m}{s} = \frac{kg\cdot m^2}{s^3}}

• In terms of electromagnetism, one watt is the rate at which work is done when one ampere (A) of current flows through an electrical potential difference of one volt (V).

Failed to parse (Missing texvc executable; please see math/README to configure.): \mathrm{W = V \cdot A}

Two additional unit conversions for watt can be found using the above equation and Ohm's Law.

Failed to parse (Missing texvc executable; please see math/README to configure.): \mathrm{W = \frac{V^2}{\Omega} = A^2\cdot\Omega}

Where ohm (Failed to parse (Missing texvc executable; please see math/README to configure.): \Omega

) is the SI derived unit of electrical resistance.

Examples[link]

• A person having a mass of 100 kilograms who climbs a 3 meter high ladder in 5 seconds is doing work at a rate of about 600 watts. Mass times acceleration due to gravity times height divided by the time it takes to lift the object to the given height gives the rate of doing work or power.^{[notes 1]}
• A laborer over the course of an 8-hour day can sustain an average output of about 75 watts; higher power levels can be achieved for short intervals and by athletes.^[1]

• A medium-sized passenger automobile engine is rated at 50 to 150 kilowatts^[2] – while cruising it will typically yield half that amount.
• A typical household incandescent light bulb has a power rating of 25 to 100 watts; fluorescent lamps typically consume 5 to 30 watts to produce a similar amount of light.

• A typical coal power station produces around 600 - 700 megawatts. A typical unit in a nuclear power plant has an electrical power output of 900 - 1300 MW.

Origin and adoption as an SI unit[link]

The watt is named after the Scottish scientist James Watt for his contributions to the development of the steam engine. The unit was recognized by the Second Congress of the British Association for the Advancement of Science in 1882. The 11th General Conference on Weights and Measures in 1960 adopted it for the measurement of power into the International System of Units (SI).

Multiples[link]

For additional examples of magnitude for multiples and submultiples of the watt, see Orders of magnitude (power)

Femtowatt[link]

The femtowatt is equal to one quadrillionth (10⁻¹⁵) of a watt. Technologically important powers that are measured in femtowatts are typically found in reference(s) to radio and radar receivers. For example, meaningful FM tuner performance figures for sensitivity, quieting and signal-to-noise require that the RF energy applied to the antenna input be specified. These input levels are often stated in dBf (decibels referenced to 1 femtowatt). This is 0.2739 microvolt across a 75 ohm load or 0.5477 microvolt across a 300 ohm load; the specification takes into account the RF input impedance of the tuner.

Picowatt[link]

The picowatt is equal to one trillionth (10⁻¹²) of a watt. Technologically important powers that are measured in picowatts are typically used in reference to radio and radar receivers, acoustics and also in the science of radio astronomy.

Nanowatt[link]

The nanowatt is equal to one billionth (10⁻⁹) of a watt. A surface area of one square meter on Earth receives one nanowatt of power from a single star of apparent magnitude +3.5. Important powers that are measured in nanowatts are also typically used in reference to radio and radar receivers.

Microwatt[link]

The microwatt is equal to one millionth (10⁻⁶) of a watt. Important powers that are measured in microwatts are typically stated in medical instrumentation systems such as the EEG and the EKG, in a wide variety of scientific and engineering instruments and also in reference to radio and radar receivers. Compact solar cells for devices such as calculators and watches are typically measured in microwatts.^[3]

Milliwatt[link]

The milliwatt is equal to one thousandth (10⁻³) of a watt. A typical laser pointer outputs about five milliwatts of light power, whereas a typical hearing aid for people consumes less than one milliwatt.^[4]

Kilowatt[link]

The kilowatt is equal to one thousand (10³) watts. This unit is typically used to express the output power of engines and the power consumption of electric motors, tools, machines, and heaters. It is also a common unit used to express the electromagnetic power output of broadcast radio and television transmitters.

One kilowatt of power is approximately equal to 1.34 horsepower. A small electric heater with one heating element can use 1.0 kilowatt, which is equivalent to the power consumption of a household in the United States averaged over the entire year (8900 kW h divided by 365×24 hours).^[5] (UK household consume about half this amount)^[6] Also, kilowatts of light power can be measured in the output pulses of some lasers.

A surface area of one square meter on Earth receives typically one kilowatt of power of sunlight from the sun (on a clear day at mid day).

Megawatt[link]

The megawatt is equal to one million (10⁶) watts. Many events or machines produce or sustain the conversion of energy on this scale, including lightning strikes; large electric motors; large warships such as aircraft carriers, cruisers, and submarines; large server farms or data centers; and some scientific research equipment, such as supercolliders, and also in the output pulses of very large lasers. A large residential or commercial building may consume several megawatts in electric power and heat.

The productive capacity of electrical generators operated by a utility company is often measured in megawatts. A typical wind turbine (or wind energy converter) has a power capacity of 1 to 3 MW. On railways, modern high-powered electric locomotives typically have a peak power output of 5 or 6 MW, although some produce much more. The Eurostar, for example, consumes more than 12 MW, while heavy diesel-electric locomotives typically produce/consume 3 to 5 MW. U.S. nuclear power plants have net summer capacities between about 500 and 1300 MW.^[7]

The earliest citing of the megawatt in the Oxford English Dictionary (OED) is a reference in the 1900 Webster's International Dictionary of English Language. The OED also states that megawatt appeared in a 28 November 1947 article in the journal Science (506:2).

Gigawatt[link]

The gigawatt is equal to one billion (10⁹) watts or 1 gigawatt = 1000 megawatts. This unit is sometimes used for large power plants or power grids. For example, by the end of 2010 power shortages in China's Shanxi province were expected to increase to 5–6 GW^[8] and the installed capacity of wind power in Germany was 25.8 GW.^[9] The largest unit (out of four) of the Belgian Nuclear Plant Doel has a peak output of 1.04 GW.^[10]

Though “gigawatt” is usually pronounced today with a velar "g", the “j” alveopalatal variant is also accepted (see giga-#Pronunciation).^[11][12]

Terawatt[link]

The terawatt is equal to one trillion (10¹²) watts. The total power used by humans worldwide (about 16 TW in 2006) is commonly measured in this unit. The most powerful lasers from the mid-1960s to the mid-1990s produced power in terawatts, but only for nanosecond time frames. The average strike of lightning peaks at 1 terawatt, but these strokes only last for 30 microseconds. The total power output of the first stage of the Apollo Saturn V moon rocket was 17 terawatts.

Petawatt[link]

The petawatt is equal to one quadrillion (10¹⁵) watts and can be produced by the current generation of lasers for time-scales on the order of femtoseconds (10⁻¹⁵ s). Based on the average of 1.366 kW/m² of total solar irradiance^[13] the total power of sunlight striking Earth's atmosphere is estimated at 174 PW (cf. Solar Constant).

Electrical and thermal watts[link]

In the electric power industry, megawatt electrical (abbreviation: MW_e^[14] or MWe^[15]) is a term that refers to electric power, while megawatt thermal or thermal megawatt^[16] (abbreviations: MW_t, MW_th, MWt, or MWth) refers to thermal power produced. Other SI prefixes are sometimes used, for example gigawatt electrical (GW_e).^{[notes 2]}

For example, the Embalse nuclear power plant in Argentina uses a fission reactor to generate 2109 MW_t of heat, which creates steam to drive a turbine, which generates 648 MW_e of electricity. The difference is due to the inefficiency of steam-turbine generators and the limitations of the theoretical Carnot Cycle.

Confusion of watts, watt-hours, and watts per hour[link]

The terms power and energy are frequently confused. Power is the rate at which energy is generated or consumed.

For example, when a light bulb with a power rating of 100W is turned on for one hour, the energy used is 100 watt-hours (W•h), 0.1 kilowatt-hour, or 360 kJ. This same amount of energy would light a 40-watt bulb for 2.5 hours, or a 50-watt bulb for 2 hours. A power station would be rated in multiples of watts, but its annual energy sales would be in multiples of watt-hours. A kilowatt-hour is the amount of energy equivalent to a steady power of 1 kilowatt running for 1 hour, or 3.6 MJ (1000 watts x 3600 seconds (i.e., 60 seconds/minute x 60 minutes/hour) = 3600000 Joules = 3.6 MJ).

Terms such as watts per hour are often misused.^[17] Watts per hour properly refers to the change of power per hour. Watts per hour (W/h) might be useful to characterize the ramp-up behavior of power plants. For example, a power plant that reaches a power output of 1 MW from 0 MW in 15 minutes has a ramp-up rate of 4 MW/h. Hydroelectric power plants have a very high ramp-up rate, which makes them particularly useful in peak load and emergency situations.

Major energy production or consumption is often expressed as terawatt-hours for a given period that is often a calendar year or financial year. One terawatt-hour is equal to a sustained power of approximately 114 megawatts for a period of one year.

The watt second is a unit of energy, equal to the joule. One kilowatt-hour is 3,600,000 watt-seconds. The watt-second is used, for example, to rate the energy storage of flash lamps used in photography, although the term joule is normally used rather than watt-second.

See also[link]

Energy portal

Notes[link]

References[link]

External links[link]

Look up watt in Wiktionary, the free dictionary.

• Nelson, Robert A., "The International System of Units Its History and Use in Science and Industry". Via Satellite, February 2000.
• Online Conversion - Power Conversion

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James Watt
Portrait of James Watt (1736-1819) by Carl Frederik von Breda
Born	(1736-01-19)19 January 1736 Greenock, Renfrewshire, Scotland
Died	25 August 1819(1819-08-25) (aged 83)[1] Handsworth, Birmingham, England
Residence	Glasgow then Handsworth, Great Britain
Citizenship	Kingdom of Great Britain
Nationality	Scottish
Fields	Inventor and Mechanical Engineer
Institutions	University of Glasgow Boulton and Watt
Known for	Improving the steam engine
Signature

James Watt, FRS, FRSE (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 his native Great Britain and the rest of the world.

While working as an instrument maker at the University of Glasgow, Watt became interested in the technology of steam engines. He realised that contemporary engine designs wasted a great deal of energy by repeatedly cooling and re-heating the cylinder. Watt introduced a design enhancement, the separate condenser, which avoided this waste of energy and radically improved the power, efficiency, and cost-effectiveness of steam engines. Eventually he adapted his engine to produce rotary motion, greatly broadening its use beyond pumping water.

Watt attempted to commercialize his invention, but experienced great financial difficulties until 1775 he entered a partnership with Matthew Boulton. The new firm of Boulton and Watt was eventually highly successful and Watt became a wealthy man. In his retirement, Watt continued to develop new inventions though none were as significant as his steam engine work. He died in 1819 at the age of 83. Watt has been described as one of the most influential figures in human history.^[2]

He developed the concept of horsepower^[3] and the SI unit of power, the watt, was named after him.

Biography[link]

James Watt was born on 19 January 1736 in Greenock, Renfrewshire, a seaport on the Firth of Clyde.^[4] His father was a shipwright, ship owner and contractor, and served as the town's chief baillie,^[5] while his mother, Agnes Muirhead, came from a distinguished family and was well educated. Both were Presbyterians and strong Covenanters.^[6] Watt's grandfather, Thomas Watt, was a mathematics teacher and baillie to the Baron of Cartsburn.^[7]

Watt did not attend school regularly; initially he was mostly schooled at home by his mother but later he attended Greenock grammar school.^[8] He exhibited great manual dexterity, engineering skills and an aptitude for mathematics, while Latin and Greek failed to interest him.

When he was eighteen, his mother died and his father's health began to fail. Watt travelled to London to study instrument-making for a year, then returned to Scotland, settling in the major commercial city of Glasgow intent on setting up his own instrument-making business. He made and repaired brass reflecting quadrants, parallel rulers, scales, parts for telescopes, and barometers, among other things. Because he had not served at least seven years as an apprentice, the Glasgow Guild of Hammermen (which had jurisdiction over any artisans using hammers) blocked his application,^[9] despite there being no other mathematical instrument makers in Scotland.^[10]

Watt was saved from this impasse by the arrival of astronomical instruments to the University of Glasgow that required expert attention.^[11] Watt restored them to working order and was remunerated. These instruments were eventually installed in the Macfarlane Observatory. Subsequently three professors offered him the opportunity to set up a small workshop within the university. It was initiated in 1757 and one of the professors, the physicist and chemist Joseph Black, became Watt's friend.^[12]

At first he worked on maintaining and repairing scientific instruments used in the university, helping with demonstrations, and expanding the production of quadrants. In 1759 he formed a partnership with John Craig, an architect and businessman, to manufacture and sell a line of products including musical instruments and toys. This partnership lasted for the next six years, and employed up to sixteen workers. Craig died in 1765. One employee, Alex Gardner, eventually took over the business, which lasted into the twentieth century.^[13]

In 1764, Watt married his cousin Margaret (Peggy) Miller, with whom he had five children, two of whom lived to adulthood: James Jr. (1769–1848) and Margaret (1767–1796). His wife died in childbirth in 1772. In 1777 he married again, to Ann MacGregor, daughter of a Glasgow dye-maker, with whom he had two children: Gregory (1777–1804), who became a geologist and mineralogist,^[14] and Janet (1779–1794). Ann died in 1832. Between 1777 and 1790 he lived in Regent Place, Birmingham^[15]

Early experiments with steam[link]

Original condenser by Watt (Science Museum (London))

In 1759 Watt's friend, John Robison, called his attention to the use of steam as a source of motive power.^[16] The design of the Newcomen engine, in use for almost 50 years for pumping water from mines, had hardly changed from its first implementation. Watt began to experiment with steam though he had never seen an operating steam engine. He tried constructing a model. It failed to work satisfactorily, but he continued his experiments and began to read everything he could about the subject. He came to realize the importance of latent heat in understanding the engine, which, unknown to Watt, his friend, Joseph Black, had previously discovered some years before. Understanding of the steam engine was in a very primitive state, for the science of thermodynamics was not in place for another 100 years or so.

In 1763, Watt was asked to repair a model Newcomen engine belonging to the University.^[16] Even after repair, this engine only barely worked. After much experimentation, Watt demonstrated that about three quarters of the heat of the steam was being wasted - consumed in heating the engine cylinder on every cycle.^[17] This energy was wasted because later in the cycle, cold water was injected into the cylinder to condense the steam to reduce its pressure. Thus the engine expended much of its energy in repeatedly heating the cylinder rather than in delivering mechanical force.

Watt's critical insight, arrived at in May 1765,^[18] was to cause the steam to condense in a separate chamber apart from the piston, and to maintain the temperature of the cylinder at the same temperature as the injected steam (by surrounding it with a "steam jacket").^[17] This meant that very little heat was absorbed into the cylinder itself on each cycle, and thus more heat from the steam was made available to perform useful work. Watt had a working model later that same year.

The ruin of Watt's cottage workshop at Kinneil House

Cylinder fragment of Watt's first operational engine at the Carron Works, Falkirk

Despite a potentially workable design, there were still substantial difficulties in constructing a full-scale engine. This required more capital, some of which came from Black. More substantial backing came from John Roebuck, the founder of the celebrated Carron Iron Works, near Falkirk, with whom he now formed a partnership. Roebuck lived at Kinneil House in Bo'ness, during which time Watt worked at perfecting his steam engine, in a cottage adjacent to the house. The shell of the cottage, and a very large part of one of his projects, still exist to the rear.^[19]

The principal difficulty was in machining the piston and cylinder. Iron workers of the day were more like blacksmiths than modern machinists and were unable to produce the components with sufficient precision. Much capital was spent in pursuing the ground-breaking patent on Watt's invention. Strapped for resources, Watt was forced to take up employment first as a surveyor, then as a Civil engineer for eight years.^[20]

Roebuck went bankrupt, and Matthew Boulton, who owned the Soho Foundry works near Birmingham, acquired his patent rights. An extension of the patent to 1800 was successfully obtained in 1775.^[21]

Through Boulton, Watt finally had access to some of the best iron workers in the world. The difficulty of the manufacture of a large cylinder with a tightly fitting piston was solved by John Wilkinson who had developed precision boring techniques for cannon making at Bersham, near Wrexham, North Wales. Watt and Boulton formed a hugely successful partnership (Boulton and Watt), which lasted for the next twenty-five years.

First engines[link]

Engraving of a 1784 steam engine designed by Boulton and Watt.

In 1776, the first engines were installed and working in commercial enterprises. These first engines were used to power pumps and produced only reciprocating motion to move the pump rods at the bottom of the shaft. The design was commercially successful, and for the next five years Watt was very busy installing more engines, mostly in Cornwall for pumping water out of mines.

These early engines were not manufactured by Boulton and Watt, but were made by others according to drawings made by Watt, who served in the role of consulting engineer. The erection of the engine and its shakedown was supervised by Watt, at first, and then by men in the firm's employ. These were large machines. The first, for example, had a cylinder with a diameter of some 50 inches and an overall height of about 24 feet, and required the construction of a dedicated building to house it. Boulton and Watt charged an annual payment, equal to one third of the value of the coal saved in comparison to a Newcomen engine performing the same work.

The field of application for the invention was greatly widened when 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 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" (i.e., using steam at pressures well above atmospheric). 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 which Watt was most proud of, was the Parallel motion which was essential 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,^[22] 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, which were in a very primitive stage of development, and the ongoing issues with leaks, Watt restricted his use of high pressure steam – all of his engines used steam at near atmospheric pressure.

Patent trials[link]

A steam engine built to James Watt's patent in 1848 at Freiberg in Germany

Edward Bull started constructing engines for Boulton and Watt in Cornwall in 1781. By 1792 he had started making engines of his own design, but which contained a separate condenser, and so infringed Watt's patents. Two brothers, Jabez Carter Hornblower and Jonathan Hornblower Jnr also started to build engines about the same time. Others began to modify Newcomen engines by adding a condenser, and the mine owners in Cornwall became convinced that Watt's patent could not be enforced. They started to withhold payments due to Boulton and Watt, which by 1795 had fallen. Of the total £21,000 (£1,660,000 as of 2012) owed, only £2,500 had been received. Watt was forced to go to court to enforce his claims.^[23]

He first sued Bull in 1793. The jury found for Watt, but the question of whether or not the original specification of the patent was valid was left to another trial. In the meantime, injunctions were issued against the infringers, forcing their payments of the royalties to be placed in escrow. The trial on determining the validity of the specifications which was held in the following year was inconclusive, but the injunctions remained in force and the infringers, except for Jonathan Hornblower, all began to settle their cases. Hornblower was soon brought to trial and the verdict of the four judges (in 1799) was decisively in favour of Watt. Their friend John Wilkinson, who had solved the problem of boring an accurate cylinder, was a particularly grievous case. He had erected about twenty engines without Boulton's and Watts' knowledge. They finally agreed to settle the infringement in 1796.^[24] Boulton and Watt never collected all that was owed them, but the disputes were all settled directly between the parties or through arbitration. These trials were extremely costly in both money and time, but ultimately were successful for the firm.

Copying machine[link]

Before 1780 there was no good method for making copies of letters or drawings. The only method sometimes used was a mechanical one using linked multiple pens. Watt at first experimented with improving this method, but soon gave up on this approach because it was so cumbersome. He instead decided to try to physically transfer some ink from the original to another sheet of paper which was thin enough for the ink to go through to the other side, thus reproducing the writing exactly.^[25]

Watt started to develop the process in 1779, and made many experiments to formulate the ink, select the thin paper, to devise a method for wetting the special thin paper, and to make a press suitable for applying the correct pressure to effect the transfer. All of these required much experimentation, but he soon had enough success to patent the process a year later. Watt formed another partnership with Boulton (who provided financing) and James Keir (to manage the business) in a firm called James Watt and Co. The perfection of the invention required much more development work before it could be routinely used by others, but this was carried out over the next few years. Boulton and Watt gave up their shares to their sons in 1794.^[26] It became a commercial success and was widely used in offices even into the twentieth century.

Chemical experiments[link]

From an early age Watt was very interested in chemistry. In late 1786, while in Paris, he witnessed an experiment by Berthollet in which he reacted hydrochloric acid with manganese dioxide to produce chlorine. He had already found that an aqueous solution of chlorine could bleach textiles, and had published his findings, which aroused great interest among many potential rivals. When Watt returned to Britain, he began experiments along these lines with hopes of finding a commercially viable process. He discovered that a mixture of salt, manganese dioxide and sulfuric acid could produce chlorine, which Watt believed might be a cheaper method. He passed the chlorine into a weak solution of alkali, and obtained a turbid solution that appeared to have good bleaching properties. He soon communicated these results to James McGrigor, his father-in-law, who was a bleacher in Glasgow. Otherwise he tried to keep his method a secret.^[27]

With McGrigor, and his wife Annie, he started to scale up the process, and in March 1788, McGrigor was able to bleach 1500 yards of cloth to his satisfaction. About this time Berthollet discovered the salt and sulphuric acid process, and published it so it became public knowledge. Many others began to experiment with improving the process, which still had many shortcomings, not the least of which was the problem of transporting the liquid product. Watt's rivals soon overtook him in developing the process, and he dropped out of the race. It was not until 1799, when Charles Tennant patented a process for producing solid bleaching powder (calcium hypochlorite) that it became a commercial success.

By 1794 Watt had been chosen by Thomas Beddoes to manufacture apparatus to produce, clean and store gases for use in the new Pneumatic Institution at Hotwells in Bristol. Watt continued to experiment with various gases for several years, but by 1797 the medical uses for the "factitious airs" had come to a dead end.^[28]

Scientific apparatus designed by Boulton and Watt in preparation of the Pneumatic Institution in Bristol

Personality[link]

Watt combined theoretical knowledge of science with the ability to apply it practically. Humphry Davy said of him that "Those who consider James Watt only as a great practical mechanic form a very erroneous idea of his character; he was equally distinguished as a natural philosopher and a chemist, and his inventions demonstrate his profound knowledge of those sciences, and that peculiar characteristic of genius, the union of them for practical application".^[29]

He was greatly respected^[30] 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.^[31] His personal relationships with his friends and partners were always congenial and long-lasting.

Watt was a prolific correspondent. During his years in Cornwall, he wrote long letters to Boulton several times per week. He was averse to publishing his results in, for example, the Philosophical Transactions of the Royal Society however, and instead preferred to communicate his ideas in patents.^[32] He was an excellent draughtsman.

He was a rather poor businessman, and especially hated bargaining and negotiating terms with those who sought to utilize the steam engine. In a letter to William Small in 1772, Watt confessed that "he would rather face a loaded cannon than settle an account or make a bargain."^[33] Until he retired, he was always much concerned about his financial affairs, and was something of a worrier. His health was often poor. He was subject to frequent nervous headaches and depression.

The Soho Foundry[link]

At first the partnership made the drawing and specifications for the engines, and supervised the work to erect it on the customers property. They produced almost none of the parts themselves. Watt did most of his work at his home in Harper’s Hill in Birmingham, while Boulton worked at the Soho Manufactory. Gradually the partners began to actually manufacture more and more of the parts, and by 1795 they purchased a property about a mile away from the Soho Manufactory, on the banks of the Birmingham Canal, to establish a new foundry for the manufacture of the engines. The Soho Foundry formally opened in 1796 at a time when Watt’s sons, Gregory and James Jr. were heavily involved in the management of the enterprise. In 1800, the year of Watt’s retirement, the firm made a total of 41 engines.^[34]

Later years[link]

"Heathfield", Watt's house in Handsworth, Birmingham

James Watt's workshop

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 soon made a partner and the firm prospered.

Watt continued to invent other things before and during his semi-retirement. 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.^[35] Among other things, he invented and constructed several machines for copying sculptures and medallions which worked very well, but which he never patented.^[36] He maintained his interest in Civil Engineering and was a consultant on several significant projects. He proposed, for example, a method for constructing a flexible pipe to be used for passing water under the Clyde at Glasgow.^[37]

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.

Murdoch's contributions[link]

James Murdoch joined Boulton and Watt in 1777. At first he worked in the pattern shop in Soho, but soon he was erecting engines in Cornwall. He became an important part of the firm and made many contributions to its success. A very able man, he made several important inventions on his own.

John Griffiths, who wrote a biography^[38] of him in 1992, has argued that Watt's discouraging Murdoch from working with high pressure steam (Watt rightly believed that boilers of the time would be unsafe) on his steam road locomotive experiments delayed its development.^[39]

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 Murdoch.^[40] The patent was never contested by Murdoch, however, 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. Murdoch was made a partner of the firm in 1810, where he remained until his retirement 20 years later at the age of 76.

Legacy[link]

A preserved Watt beam engine at Loughborough University

James Watt's improvements to the steam engine "converted it from a prime mover of marginal efficiency into the mechanical workhorse of the Industrial Revolution".^[41] The availability of efficient, reliable motive power made whole new classes of industry economically viable, and altered the economies of continents.^[42] In doing so it brought about immense social change, attracting millions of rural families to the towns and cities.

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."^[43]

Honours[link]

Watt was much honoured in his own time. In 1784 he was made a fellow of the Royal Society of Edinburgh, and was elected as a member of the Batavian Society for Experimental Philosophy, of Rotterdam in 1787. In 1806 he was conferred the honorary Doctor of Laws by the University of Glasgow. The French Academy elected him a Corresponding Member and he was made a Foreign Associate in 1814.^[44]

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").

On 29 May 2009 the Bank of England announced that Boulton and Watt would appear on a new £50 note. The design is the first to feature a dual portrait on a Bank of England note, and presents the two industrialists side by side with images of Watt's steam engine and Boulton's Soho Manufactory. Quotes attributed to each of the men are inscribed on the note: "I sell here, sir, what all the world desires to have—POWER" (Boutlon) and "I can think of nothing else but this machine" (Watt). The inclusion of Watt is the second time that a Scot has featured on a Bank of England note (the first was Adam Smith on the 2007 issue £20 note).^[45] In September 2011 it was announced that the notes would enter circulation on 2 November.^[46]

Memorials[link]

The James Watt Memorial College in Greenock.

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.^[47]

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.^[48] It remained on display for visitors for many years, but was walled-off when the gallery it was housed in closed. The workshop remained intact, and preserved, and in March 2011 was put on public display as part of a new permanent Science Museum exhibition, "James Watt and our world".^[49]

The approximate location of James Watt's birth in Greenock is commemorated by a statue. 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, as well as several others in Birmingham, where he is also remembered by the Moonstones and a school is named in his honour.

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. Matthew Boulton's home, Soho House, is now a museum, commemorating the work of both men. The University of Glasgow's Faculty of Engineering has its headquarters in the James Watt Building, which also houses the department of Mechanical Engineering and the department of Aerospace Engineering. The huge painting James Watt contemplating the steam engine by James Eckford Lauder is now owned by the National Gallery of Scotland.

Chantrey's statue of James Watt

There is a statue of James Watt in Piccadilly Gardens, Manchester and City Square, Leeds.

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, in part, "JAMES WATT ... 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."

Patents[link]

Watt was the sole inventor listed on his six patents:^[50]

• Patent 913 A method of lessening the consumption of steam in steam engines-the separate condenser. The specification was accepted on 5 January 1769; enrolled on 29 April 1769, and extended to June 1800 by an act of Parliament in 1775.
• Patent 1,244 A new method of copying letters; The specification was accepted on 14 February 1780 and enrolled on 31 May 1780.
• Patent 1,306 New methods to produce a continued rotation motion – sun and planet. The specification was accepted on 25 October 1781 and enrolled on 23 February 1782.
• Patent 1,321 New improvements upon steam engines – expansive and double acting. The specification was accepted on 14 March 1782 and enrolled on 4 July 1782.
• Patent 1,432 New improvements upon steam engines – three bar motion and steam carriage. The specification was accepted on 28 April 1782 and enrolled on 25 August 1782.
• Patent 1,485 Newly improved methods of constructing furnaces. The specification was accepted on 14 June 1785 and enrolled on 9 July 1785.

Notes and references[link]

Bibliography[link]

• "Some Unpublished Letters of James Watt" in Journal of Institution of Mechanical Engineers (London, 1915).
• Carnegie, Andrew, James Watt University Press of the Pacific (2001) (Reprinted from the 1913 ed.), ISBN 0-89875-578-6.
• Dickinson, H. W. (1935). James Watt: Craftsman and Engineer. Cambridge University Press. 
• H. W. Dickinson and Hugh Pembroke Vowles James Watt and the Industrial Revolution (published in 1943, new edition 1948 and reprinted in 1949. Also published in Spanish and Portuguese (1944) by the British Council)
• Hills, Rev. Dr. Richard L., James Watt, Vol 1, His time in Scotland, 1736-1774 (2002); Vol 2, The years of toil, 1775-1785; Vol 3 Triumph through adversity 1785-1819. Landmark Publishing Ltd, ISBN 1-84306-045-0.
• Hulse David K. (1999). The early development of the steam engine. Leamington Spa, UK: TEE Publishing. pp. 127–152. ISBN 1-85761-107-1. 
• Hulse David K. (2001). The development of rotary motion by steam power. Leamington, UK: TEE Publishing Ltd.. ISBN 1-85761-119-5. 
• Marsden, Ben. Watt's Perfect Engine Columbia University Press (New York, 2002) ISBN 0-231-13172-0.
• Thomas H. Marshall (1925), James Watt, Chapter 3: Mathematical Instrument Maker, from Steam Engine Library of University of Rochester Department of History.
• Thomas H. Marshall (1925) James Watt, University of Rochester Department of History.
• Muirhead, James Patrick (1854). Origin and Progress of the Mechanical Inventions of James Watt. London: John Murray. http://books.google.com/?id=9lspAAAAYAAJ&printsec=frontcover&dq=Origin+and+Progress+of+the+Mechanical+Inventions+of+James+Watt.. 
• Muirhead, James Patrick (1858). The Life of James Watt. London: John Murray. http://books.google.com/?id=zUE6AAAAcAAJ&printsec=frontcover&dq=The+life+of+James+Watt+with+selections+from+his+correspondence. 
• Roll, Erich (1930). An Early Experiment in Industrial Organisation : being a History of the Firm of Boulton & Watt. 1775-1805. Longmans, Green and Co.
• Samuel Smiles, Lives of the Engineers, (London, 1861–62, new edition, five volumes, 1905).

Related topics

• Schofield, Robert E. (1963). The Lunar Society, A Social History of Provincial Science and Industry in Eighteenth Century England. Clarendon Press. 
• Uglow, Jenny (2002). The Lunar Men. London: Farrar, Straus and Giroux. 

External links[link]

Wikiquote has a collection of quotations related to: James Watt

Wikimedia Commons has media related to: James Watt

• James Watt by Andrew Carnegie (1905)
• James Watt by Thomas H. Marshall (1925)
• Archives of Soho at Birmingham Central Library.
• BBC History: James Watt
• Revolutionary Players website
• Cornwall Record Office Boulton and Watt letters
• Significant Scots - James Watt
• "Chapter 8: The Record of the Steam Engine". www.history.rochester.edu. http://www.history.rochester.edu/steam/carnegie/ch8.html. Retrieved 2009-07-06. 

vep:Uatt Džeims

Hannah Storm
Storm at the 2008 Tribeca Film Festival
Born	Hannah Storen (1962-06-13) June 13, 1962 (age 50) Oak Park, Illinois USA
Occupation	Television Journalist, Television personality, Author, Sports anchor
Years active	1984–present
Spouse	Dan Hicks (1994–present)

Hannah Storm (born Hannah Storen June 13, 1962) is an American television sports journalist, serving as co-anchor of ESPN's SportsCenter Monday–Thursday mornings, and is also host of the NBA Countdown pregame show on ABC as part of the network's NBA Sunday game coverage, until 2011.

Early life and career[link]

Storm was born in Oak Park, Illinois, and is the daughter of sports executive Mike Storen, who was a commissioner of the American Basketball Association, general manager of that league's Indiana Pacers, Kentucky Colonels and Memphis Sounds franchises, and president of the Atlanta Hawks in the NBA. Her mother, Hannah G. Storen, is a successful real estate agent in Houston, Texas. She graduated from Westminster Schools of Atlanta in 1979 and the University of Notre Dame in 1983, with degrees in political science and communications. She is married to sportscaster Dan Hicks. The couple have three daughters: Riley, Ellery and Hannah.^[1]

Storm took her on-air name during her stint as a disc jockey for a hard rock radio station in Corpus Christi, Texas, in the early 1980s. While at Notre Dame, she worked for WNDU-TV, the Notre Dame-owned NBC affiliate in South Bend, Indiana. After graduation, she took a job as a disc jockey at KNCN-FM (C-101) in Corpus Christi, Texas. Six months later, she got a job at a Houston rock station KSRR 97 Rock as the drive-time sportscaster. Storm stayed in Houston for four years doing a variety of radio and television jobs, including hosting the Houston Rockets halftime and postgame shows and also hosted Houston Astros postgame shows on television. She worked as a very popular weekend sports anchor on WCNC TV 36 (formerly WRET) in Charlotte, NC in 1988-89. She made the leap to CNN from there.

Professional career[link]

CNN[link]

Storm's national experience began as the first female host on CNN Sports Tonight from 1989 to 1992. She also hosted Major League Baseball Preview and reported from Spring training, the playoffs, and Daytona 500. In addition, she hosted the 1990 Goodwill Games for TBS.

NBC Sports[link]

In May 1992, Storm left CNN and was hired by NBC. She hosted for the Olympic Games, as well as NBA and WNBA basketball, the National Football League, figure skating and Major League Baseball. Storm became the first woman in American television history to act as solo host of a network's sports package when she hosted NBC Major League Baseball games from 1994 to 2000 (CBS' Andrea Joyce preceded her, but co-hosted the sports packages). She then hosted The NBA on NBC from 1997 to 2002. Storm also anchored NBC Sports coverage of Wimbledon, French Open, Notre Dame football, World Figure Skating Championships, NBC SportsDesk, Men's and Women's U.S. Open (golf) and various college bowl games. Storm was also the first play-by-play announcer for the WNBA in 1997.

[edit] The Early Show

In October 2002, she moved to CBS News and became one of the hosts of The Early Show. As co-host of The Early Show, she covered major news events, including the Iraq War, Hurricane Katrina, Super Bowls XLI and XXXVIII, the 2004 Democratic National Convention, the 2004 U.S. presidential election, 2008 presidential elections and the 2005 London terrorist bombings. Storm has interviewed major newsmakers such as President George W. Bush, First Lady Laura Bush, Secretary of State Condoleezza Rice and Senators John McCain, Hillary Clinton and Barack Obama, as well as many sports and pop culture icons, including Elton John, Paul McCartney, Peyton Manning, Tiger Woods, Jamie Foxx, Halle Berry and Jennifer Aniston.

In addition to her duties on The Early Show, Storm hosted shows for the award-winning CBS newsmagazine, 48 Hours. She also served as co-host of the network's CBS Thanksgiving Day Parade for five years. In 2007, Storm conceived and wrote a daily blog for CBSNEWS.com, which featured behind-the-scenes insight and stories of inspirational women.

During an Early Show on-air segment, Storm revealed on camera that she had a congenital defect known as port-wine stain under her left eye.

In November 2007, CBS announced that Storm was leaving The Early Show. Storm's last day as an The Early Show co-host was December 7, 2007.

ESPN/ABC[link]

Storm joined ESPN on May 10, 2008. She anchors SportsCenter weekdays (except Fridays during the NFL season) from 9 a.m. until noon and the Sunday mornings during the NFL season with Bob Ley. Her duties are to deliver highlights and to question analysts about sports topics.

In August 2009, she added tennis host to her ESPN duties by co-hosting the 2009 U.S. Open with Mike Tirico and Chris Fowler. She also co-hosted the 2010 U.S. Open and 2011 Wimbledon.

In February 2010, fellow ESPN colleague Tony Kornheiser criticized her outfit that day on his radio show, saying that her outfit looked like: "A sausage casing", and was suspended from ESPN for two weeks. He has since apologized to her via a 15-minute phone conversation.^[2] Beginning on April 3, 2010, Storm would host ESPN Sports Saturday, a show on corporate sibling ABC similar to that network's classic sports series, Wide World of Sports.^[3]

In June 2010, alongside fellow anchor Stuart Scott, she provided the lead coverage for the 2010 NBA Finals between the Boston Celtics and Los Angeles Lakers, and then would become host of the NBA Countdown pregame show for the 2010-2011 season, alternating with Stuart Scott, until the 2011-12 NBA season.

Other notable accomplishments[link]

Storm has written two books: Go Girl, a parenting guide for raising daughters to participate in sports, which is in its second printing, and Notre Dame Inspirations, which funds a journalism scholarship in her name at her alma mater. She has also contributed extensively to several magazines, including Cosmopolitan, Nick Jr., Family Circle, Child, and Notre Dame Magazine.

In 2008 Storm created the Hannah Storm Foundation, which raises awareness and provides treatment for children suffering from debilitating and disfiguring vascular birthmarks. She also sits on the boards of the Tribeca Film Festival, Colgate Women's Sports Awards, 21st Century Kids 1st Foundation, and has done extensive work with the March of Dimes, Partnership for Drug-Free America, Boys and Girls Club, Special Olympics, the Women's Sports Foundation, Vascular Birthmark Institute, University of Notre Dame, and the Diocese of Bridgeport. Storm also founded Brainstormin' Productions for the creation of educational and inspirational programming. In May 2011, Hannah received "Celebrated Mom" award from LifeWorx, Inc, Chappaqua, NY. This award is given a Mom who inspires others, in spite of career and family challenges.

Career timeline[link]

• 1989–1992: CNN Sports Tonight Anchor^[4]
• 1995, 1997, 1999: World Series Hostess^[4]
• 1997–2002: NBA on NBC Hostess^[4]
• 1997: WNBA on NBC Play-by-Play^[4]
• 2002–2007: The Early Show Co-Hostess^[4]
• 2008–present: SportsCenter Anchor^[4]
• 2010–2011: NBA Countdown Hostess^[4]

Hannah Received the "Celebrated Mom" Award from LifeWorx, Inc, Chappaqua, NY in May, 2011.

Books[link]

• Notre Dame Inspirations: The University's Most Successful Alumni Talk About Life, Spirituality, Football-and Everything Else Under the Dome, Doubleday, 2006. ISBN 978-0-385-51812-3
• Go Girl! Raising Healthy Confident and Successful Daughters through Sports, Sourcebooks, 2002/2011

References[link]

This article includes a list of references, related reading or external links, but its sources remain unclear because it lacks inline citations. Please improve this article by introducing more precise citations. (August 2008)

External links[link]

• Hannah Storm's ESPN Bio
• Morgan, John (2004-03-16). "Hannah Storm reveals truth about vascular birthmarks". USA Today. http://www.usatoday.com/news/health/spotlighthealth/2004-03-16-storm_x.htm. Retrieved 2005-11-05. 
• "Hannah Storm: Early Show Anchor". The Early Show. 2002-10-14. http://www.cbsnews.com/stories/2002/10/14/earlyshow/bios/main525455.shtml. Retrieved 2005-11-05.