جيمس واط

هذا المقال هو عن the inventor and mechanical engineer. إذا كنت تريد the college، انظر James Watt College. إذا كنت تريد the award، انظر James Watt International Medal. إذا كنت تريد other people with similar names، انظر James Watt (disambiguation).

جيمس واط James Watt "جيمس وات" مخترع المحرك البخاري وُلِدَ (1736-01-19)19 يناير 1736 گرينوك، أسكتلندا توفي 25 أغسطس 1819(1819-08-25) (aged 83) Handsworth, برمنجهام، إنگلترة المثوى St. Mary's Church, Handsworth القومية British عـُرِف بـ Watt steam engine Watt's linkage Watt's curve Separate condenser Centrifugal governor Horsepower Indicator diagram Letter copying press Sun and planet gear الزوج Margaret Miller (m. 1764–1773 her death) Anne McGrigor ​ (m. 1776)​ الأنجال 4 السيرة العلمية المجالات مخترع ومهندس ميكانيكي الهيئات جامعة گلاسگو Boulton and Watt التوقيع

Statue of Watt (Hunterian Museum, Glasgow, by Francis Chantrey)

جيمس واط (30 يناير 1736 – 19 يناير 1819) مخترع اسكتلندي أعطى للعالم إحدى أعظم الآلات في التاريخ (المحرك البخاري المكثف) التي فجرت الثورة الصناعية، ولم يكن وات أول من اخترع الآلة البخارية، فقد سبقته محاولات كثيرة من قبله، لكن تلك الآلات السابقا كانت ضعيفة الجهد بدرجة أنهم كانوا يستخدمونها فقط في ضخ الماء من المناجم، وتشارك وات مع المهندس الإنكليزي ماتيو بارلتون وعمل الاثنان في إنشاء معمل لتصنيع مخترعات وات ومن اكتشافاته الأخرى المقياس المائي والعنفة البحرية والناظم النابذ لتنظيم سرعة المحرك.

ولقد كانت الآلة البخارية ذروة الثورة الصناعية لا ثمرة لها تماماً. ولا داعي للرجوع بالذاكرة إلى هيرو الإسكندري (200 م؟)، لأن دنتن بابين وصف جميع مكونات ومبادئ آلة بخارية عملية في عام 1690. ثم صنع توماس سافري مضخة يديرها البخار في 1698. وطورها توماس نيوكومن (1708-12) إلى آلة يكثف فيها تيار متدفق من الماء البارد البخاري المولد من الماء المحمي، ويدفع فيها بالتناوب ضغط الهواء كباساً إلى أعلى وأسفل؛ هذه "الآلة الهوائية" ظلت الآلة القياسية حتى حولها جيمس وات إلى آلة بخارية حقيقية في 1765.

 السيرة

 النشأة والتعليم

وكان وات بخلاف معظم مخترعي ذلك الجيل طالباً كما كان رجلاً عملياً. كان جده معلم رياضيات، وأبوه معمارياً وبناء سفن وقاضياً في بلدة جرينوك في جنوب غربي إسكتلندة. ولم يحظ جيمس بتعليم جامعي، ولكنه كان ذا تطلع خارق واستعداد ميكانيكي. ويعرف نصف العالم قصته مع عمته التي وبخته قائلة "لم أر قط ولداً خاملاً مثلك... فإنك لم تنطق بكلمة واحدة طوال هذه الساعة، بل نزعت غطاء تلك الغلاية، ثم أعدته إلى مكانه، ثم أمسكت تارة قلنسوة وتارة ملعقة فضية فوق البخار ملاحظاً كيف يتصاعد من البزبوز، وممسكاً بالقطرات محصياً إياها(11)". وفي القصة رائحة الأسطورة، ولكن مخطوطاً خلفه جيمس وات بخط يده يصف تجربة فيها "ثبت الطرف المستقيم لأنبوب على بزبوز غلاية شاي"، وجاء في مخطوطة أخرى: "أخذت أنبوبة زجاجية ملوية وأدخلتها في فم غلاية الشاي، وغمرت الطرف الآخر في ماء بارد"(12).

 الدراسات العلمية والاختراعات

 وات والغلاية

وحين بلغ وات العشرين (1756) حاول أن يبدأ عمله في جلاسجو صانعاً للأدوات العلمية. أبت عليه نقابات حرف المدينة الرخصة بحجة أنه لم يكمل التلمذة كلها، ولكن جامعة جلاسجو أعطته ورشة داخل أرضها. واختلف إلى محاضرات الكيمياء التي يلقيها جوزيف بلاك، وكسب صداقته ومساعدته، واهتم خاصة بنظرية بلاك في الحرارة الكامنة(13).

ثم تعلم الألمانية والفرنسية والإيطالية ليقرأ الكتب الأجنبية بما فيها كتب الميتافيزيقا والشعر. وقد راع السير جيمس روبيسون تنوع معلوماته، وكان يعرفه في تلك الآونة (1758)، فقال "رأيت صانعاً ولم أتوقع أكثر من هذا، ولكني وجدت فيلسوفاً"(14).

 التجارب المبكرة مع البخار

James Eckford Lauder: James Watt and the Steam Engine: the Dawn of the Nineteenth Century, 1855

Original condenser by Watt (Science Museum)

وفي 1763 طلبت إليه الجامعة أن يصلح نموذجاً من آلة نيوكومن كان يستعمل في تدريس الفيزياء. وأدهشته أن ثلاثة أرباع الحرارة التي تمد بها الآلة تضيع هباء، فبعد كل ضربة كباس تفقد الأسطوانة الحرارة من جراء استعمال الماء البارد لتكثيف كمية البخار الجديدة التي تدخل الأسطوانة، فقد كان قدر كبير من الطاقة يتبدد حتى حكم أكثر أصحاب المصانع بأن الآلة غير مجزية. واعتزم وات تكثيف البخار في وعاء منفصل لا تؤثر درجة حرارته المنخفضة في الأسطوانة التي يتحرك فيها الكباس. وزاد هذا "المكثف" كفاءة الآلة في نسبة الوقود المستعمل إلى العمل المؤدي قرابة ثلاثمائة في المائة. ويضاف إلى هذا أن الكباس بفضل إصلاح وات للآلة أخذ يحركه تمدد البخار لا الهواء؛ لقد صنع وات آلة بخارية لا مراء فيها.

أما الانتقال من الخطط والنماذج إلى التطبيق العملي فقد أفنى اثني عشر عاماً من حياة وات. ولكي يصنع عينات ويحدث تحسينات متعاقبة في آلته اقترض أكثر من ألف جنيه، وأكثرها من جوسف بلاك، الذي لم يفقد إيمانه به قط. وتنبأ جون سميتن، وكان هو نفسه مخترعاً ومهندساً، بأن آلة وات لا يمكن "تعميم استعمالها أبدأ لصعوبة تصنيع أجزائها بالدقة الكافية"(15)، وفي 1765 تزوج وات، وكان عليه أن يكسب مزيداً من المال، فنحى اختراعه وعكف على أعمال المساحة والهندسة، فرسم تصميمات الثغور والكباري والقنوات. وخلال ذلك قدمه لاك إلى جون روبك الذي كان يبحث عن آلة أكثر فاعلية من آلة نيوكومن لضخ الماء من مناجم الفحم التي تمد بالوقود مصانع الحديد التي يملكها في كارون. وفي 1767 وافق على أن يدفع ديون وات ويزوده برأس المال اللازم لصنع آلات طبق مواصفات وات، وذلك لقاء ثلثي الأرباح التي تتحقق من التركيبات أو المبيعات. ورغبة في حماية استثمارهما طلب وات في 1769 إلى البرلمان براءة اختراع تعطيه دون غيره حق إنتاج آلته، فمنح البراءة حتى عام 1783. وأقام هو وروبك آلة بخارية قرب إدنبره، ولكن صنعة الحدادين الرديئة تسببت في فضلها؛ وفي بعض الحالات كانت الأسطوانات التي صنعت لوات أكبر في قطرها ثمن بوصة في طرف منها في الآخر.

وباع روبك نصيبه في الشركة إلى ماثيو بولتن (1773) بعد أن فتت النكسات في عضده. وبدأ الآن ارتباط ملحوظ في تاريخ الصداقة كما هو ملحوظ في تاريخ الصناعة. ذلك أن بولتني لم يكن مجرد إنسان يجري وراء الربح، فلقد بلغ اهتمامه بتحسين طرائق الإنتاج وميكانيكياته حداً أفقده ثروته في هذا سبيل. ففي 1760 تزوج وهو في الثالثة والثلاثون من أرملة غنية، وكان في وسعه أن يتقاعد ويعيش على دخلها، ولكنه بدلاً من هذا بنى في سوهو قرب برمنجهام مصنعاً من أكبر مصانع إنجلترا، يقوم بصنع أنواع كثيرة من الأدوات المعدنية من مشابك الأحذية إلى الثريات. وكلن يعتمد على القوة المائية لتشغيل الآلات في مباني مصنعه الخمسة ثم اعتزم أن يجرب قوة البخار. وكان على علم بأن وات أثبت عدم كفاية آلة نيوكومن، وأن آلة وات فشلت بسبب الأسطوانات التي ثقبت بغير دقة، فغامر مغامرة محسوبة مفترضاً أن هذا العيب يمكن التغلب عليه. وفي 1774 نقل آلة وات إلى سوهو، وفي 1775 لحق به وات. ومد البرلمان أجل البراءة من 1783 إلى 1800.

وفي 1775 أخترع كبير الحدادين ولكنسن قضيب ثقب أسطوانياً مجوفاً مكن بولتن ووات من إنتاج آلات ذات قوة وكفاية لم يسبق لهما نظير، وسرعان ما أخذت الشركة الجديدة تبيع الآلات البخارية لأصحاب المصانع والمناجم في طول بريطانيا وعرضها. وقد زار بوزويل سوهو في 1776 وكتب يقول:

"لقد تفضل على مستر هكتور بمرافقتي لرؤية مصانع مستر بولتن الكبرى... ووددت لو كان جونسن معنا، لأنه كان مشهداً كان يسرني أن أتأمله على ضوء علمه. ولقد كانت ضخامة بعض الآلات وتعقدها خليقة بأن تكون تقريعاً لعقله الجبار. ولن لأنسى ما حييت عبارة مستر بولتن التي قالها لي "إنني يا سيدي أبيع هنا ما يريد العالم كله أن يملكه-القوة المحركة". وكان يشتغل بمصنعه نحو سبعمائة نفس. وقد رأيت فيه "زعيم قبيلة حديدياً، وبدا أنه أب لقبيلته"(16).

 المحركات الأولى

Steam engine designed by Boulton & Watt. Engraving of a 1784 engine.

المقالة الرئيسية: Watt steam engine, Watt's linkage, and Watt's curve

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.

Boulton and Watt did not have their own foundry until Soho foundry opened in 1795, so the main castings and cylinders 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, with the actual work being accomplished by the purchaser of the engine. Supervising erectors included at various times William Murdoch, John Rennie, William Playfair, John Southern, Logan Henderson, James Lawson, William Brunton, Isaac Perrins, and others.

These were large machines. The first, for example, had a cylinder with a diameter of 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 his 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 other improvements and modifications to the steam engine. A double-acting engine, in which the steam acted alternately on both 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 linkage, 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, to keep it from "running away" were very important. These improvements taken together produced an engine which was up to five times as fuel efficient 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.

 محاكمات براءة الاختراع

Reproduction of James Watt's steam engine

على أن آلات وات البخارية كانت لا تزال ناقصة، وقد جاهد على الدوام لتحسينها. ففي 1781 سجل اختراعاً تحول فيه حركة الكباس المتناوبة إلى حركة دوارة، مما جعل الآلة البخارية صالحة لإدارة المكنات العادية. وفي 1782 سجل آلة بخارية ثنائية العمل، يتلقى فيها طرفا الأسطوانة دفعين من الغلاية والمكثف. وفي 1788 سجل اختراع "ضابط على شكل بلية طيارة" ينظم تدفق البخار ليزيد من السرعة المتماثلة في الآلة. وخلال سنوات التجريب هذه كان مخترعون آخرون يصنعون آلات منافسة، وكان على وات أن ينتظر حلول عام 1783 حتى تسدد مبيعاته ديونه وتبدأ في أن تؤتي ثمراتها. فلما انتهت فترة براءته اعتزل العمل النشيط، وواصل العمل في شركة بولتن ووات أبناؤهما. وتسلى وات بالاختراعات الصغيرة، واستمتع بشيخوخة رضية، ومات 1819 وقد بلغ الثالثة والثمانين.

أدخل تحسينات أساسية عام 1765 م على آلة نيوكومن البخارية مما أدى إلى انتشار استخدام الطاقة البخارية في كثير من المصانع.

Edward Bull started constructing engines for Boulton and Watt in Cornwall in 1781. By 1792, he had started making engines of his own design that contained a separate condenser, thereby infringing Watt's patents. Two brothers, Jabez Carter Hornblower and Jonathan Hornblower Junior, also began building 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 to Boulton and Watt, which by 1795 had fallen on hard times. Of the total £21,000 (equivalent to £1٬660٬000 as of 2021) owed, only £2,500 had been received. Watt was forced to go to court to enforce his claims.

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 in 1799, and the verdict of the four 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 20 engines without Boulton's and Watts' knowledge. They finally agreed to settle the infringement in 1796. 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

Portable Copying Machine by James Watt & Co. 1795ح. 1795

Before 1780, there was no good method for making copies of letters or drawings. The only method sometimes used was a mechanical one using multiple linked 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 ink from the front of the original to the back of another sheet, moistened with a solvent, and pressed to the original. The second sheet had to be thin, so that the ink could be seen through it when the copy was held up to the light, thus reproducing the original exactly.

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. It became a commercial success and was widely used in offices even into the 20th century.

 Chemical experiments

From an early age, Watt was very interested in chemistry. In late 1786, while in Paris, he witnessed an experiment by Claude Louis 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 sulphuric 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.

With McGrigor and his wife Annie, he started to scale up the process, and in March 1788, McGrigor was able to bleach 1،500 ياردة (4،500 أقدام) 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 apparatuses to produce, clean and store gases for use in the new Pneumatic Institution at Hotwells in Bristol. Watt continued to experiment with various gases, but by 1797, the medical uses for the "factitious airs" (artificial gases) had come to a dead end.

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

 Personality

Watt combined theoretical knowledge of science with the ability to apply it practically. The chemist Humphry Davy said of him, "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".

He was greatly respected by other prominent men of the Industrial Revolution. He was an important member of the Lunar Society of Birmingham, and was a much sought-after conversationalist and companion, always interested in expanding his horizons. His personal relationships with his friends and business partners were always congenial and long-lasting.

According to Lord Liverpool (Prime Minister of the UK),

A more excellent and amiable man in all the relations of life I believe never existed.

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. He was an excellent draughtsman.

James Watt's letters from the Science Museum Library & Archives in Wroughton, near Swindon

He was a rather poor businessman, and especially hated bargaining and negotiating terms with those who sought to use 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." Until he retired, he was always very concerned about his financial affairs, and was something of a worrier. His health was often poor and he suffered frequent nervous headaches and depression. When he retired in 1800, he became a rich enough man to pass the business on to his sons.

 Soho Foundry

At first, the partnership made the drawings and specifications for the engines, and supervised the work to erect them 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.

 السنوات اللاحقة

An 1835 painting of "Heathfield", Watt's house in Handsworth, by Allen Edward Everitt

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 Robinson Boulton and James Watt, Junior. The long-time 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, Staffordshire, Watt made use of a garret room as a workshop, and it was here that he worked on many of his inventions. Among other things, he invented and constructed machines for copying sculptures and medallions which worked very well, but which he never patented. One of the first sculptures he produced with the machine was a small head of his old professor friend Adam Smith. 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 pumping water under the River Clyde at Glasgow.

He and his second wife travelled to France and Germany, and he purchased an estate in mid-Wales at Doldowlod House, one mile south of Llanwrthwl, which he much improved.

In 1816, he took a trip on the paddle-steamer Comet, a product of his inventions, to revisit his home town of Greenock.

He died on 25 August 1819 at his home "Heathfield Hall" near Handsworth in Staffordshire (now part of Birmingham) at the age of 83. He was buried on 2 September in the graveyard of St Mary's Church, Handsworth. The church has since been extended and his grave is now inside the church.

 العائلة

On 14 July 1764, Watt married his cousin Margaret Miller (d. 1773). They had two children, Margaret (1767–1796) and James (1769–1848). In 1791, their daughter married James Miller. In September 1773, while Watt was working in the Scottish Highlands, he learned that his wife, who was pregnant with their third child, was seriously ill. He immediately returned home but found that she had died and their child was stillborn.

On 29 July 1776, he married Ann MacGregor (d. 1832).

 الماسونية

He was Initiated into Scottish Freemasonry in The Glasgow Royal Arch Lodge, No. 77, in 1763. The Lodge ceased to exist in 1810. A Masonic Lodge was named after him in his home town of Glasgow – Lodge James Watt, No. 1215.

 Murdoch's contributions

William 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 including important inventions of his own.

John Griffiths, who wrote a biography of him in 1992, has argued that Watt's discouragement of Murdoch's work with high-pressure steam on his steam road locomotive experiments delayed its development: Watt rightly believed that boilers of the time would be unsafe at higher pressures.

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. 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.

 الذكرى

A preserved Watt beam engine at Loughborough University

للمزيد من المعلومات: الثورة الصناعية

As one author states, Watt's improvements to the steam engine "converted it from a prime mover of marginal efficiency into the mechanical workhorse of the Industrial Revolution".

 التكريم

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, the Netherlands, in 1787. In 1789, he was elected to the elite group, the Smeatonian Society of Civil Engineers. 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.

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. Quotations attributed to each of the men are inscribed on the note: "I sell here, sir, what all the world desires to have—POWER" (Boulton) 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). In September 2011, it was announced that the notes would enter circulation on 2 November.

In 2011, he was one of seven inaugural inductees to the Scottish Engineering Hall of Fame.

 نصب تذكارية

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.

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. 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".

The approximate location of James Watt's birth in Greenock is commemorated by a statue. Other memorials in Greenock include street names and 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 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 VI and I, 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 Francis Legatt 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".

A bust of Watt is in the Hall of Heroes of the National Wallace Monument in Stirling, Scotland.

A large statue of Watt – paired with one of George Stephenson – adorns the main façade of Budapest Keleti station.

The French Navy submarine Watt was named for Watt.

 براءات الاختراع

Watt was the sole inventor listed on his six patents:

• 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.

 ذكراه

James Watt statue on City Square at Leeds.

Watt celebrated in a statue by Alexander Munro in Chamberlain Square, outside Birmingham Central Library

تكريماً لإنجازاته أطلق اسمه على وحدة القدرة الكهربائية (الواط) والواط وحدة لقـياس القـوة الميكانيكـية، أو الكهربائية والواط الواحد يساوي نقلا لطاقة 1 جول في مدة 1 ثانية و(الكيلو واط) 1.34 حصان.

 المراجع

 المصادر

• "Some Unpublished Letters of James Watt". 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.
• Dickinson, H. W.; Vowles, Hugh Pembroke (1949) [1943]. James Watt and the Industrial Revolution.
• 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.
• Marshall, Thomas H. (1925), James Watt, Chapter 3: Mathematical Instrument Maker, from Steam Engine Library of University of Rochester Department of History.
• Marshall, Thomas H. (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.
• Muirhead, James Patrick (1858). The Life of James Watt. London: John Murray. 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.
• Smiles, Samuel, 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. ISBN 9780374194406.

 وصلات خارجية

• James Watt by Andrew Carnegie (1905)
• Librivox audiobook: James Watt by Andrew Carnegie (1905)
• James Watt by Thomas H. Marshall (1925)
• Archives of Soho Archived 31 أكتوبر 2011 at the Wayback Machine at Birmingham Central Library.
• BBC History: James Watt
• Scottish Engineering Hall of Fame – James Watt
• Revolutionary Players website
• Cornwall Record Office Boulton and Watt letters
• Significant Scots – James Watt
• "Chapter 8: The Record of the Steam Engine". history.rochester.edu. Archived from the original on 8 July 2009. Retrieved 6 July 2009.