James Watt is one of the most acclaimed personalities in physics. His work became a helpful contribution during the Industrial Revolution, which later became the bedrock of innovation in machineries.He is popularly accredited for his invention of the steam engine. In fact he modified the engine of Thomas Newcomen to the extent that it became a practical, efficient machine capable of application to a variety of industrial tasks.
Watt’s engine focused on the conversion of heat to mechanical work. It helped improve the understanding on the efficiency of heat engines which led to the development of the field of physics called thermodynamics.(http://www.newworldencyclopedia.org/entry/James_Watt)James Watt was born in Greenock, Scotland on January 19, 1736 to a chandler and joiner. Throughout his life he suffered serious attacks of migraines and toothaches,and at school both his peers and teachers took a poor view of this weakness.
(Porter, Ogilve, 2000) He was a thin and weakly child. At grammar school, he fell in love with mathematics, but the recurrent attacks of migraine led him to stop going to school, so he devoted his time working in his father’s workshop instead. Watt felt happy with working in his father’s workshop so much that he did not go back to school.Watt learned carpentry from his father.
His father primarily worked in shipbuilding and he taught Watt on how to build ships and crafts. Soon, Watt developed great skill in ship navigation, quadrants, telescopes, and compasses, and by his mid-teens he wanted to become an instrument maker. (Porter, Ogilve, 2000)His father was supportive of him. Unfortunately, there was no opportunity for Watt to train in making instruments in Greenock because there were no instrument-makers there, so on advice, Watt went to Glasgow, Scotland in 1754, in an attempt to become an apprentice in instrument making. In Glasgow, he worked with an optician and worked as an odd-job man for a year. (Porter, Ogilve, 2000)In Glasgow, Watt became acquainted with a scientist named Robert Dick. (http://www.
egr.msu.edu/~lira/supp/steam/wattbio.html)Robert Dick, a university scientist, was impressed with Watt’s basic skills and knowledge in instrument making that he advised Watt to further hone his skills in this trade in London.In London, Watt discovered that he could not get an apprenticeship because the instrument makers protected their trade by rules of a body known as the Worshipful Company of Clock-makers. The only employment was for fully-trained instrument makers or trainees serving seven-year apprenticeships.
Eventually, he was able to secure a position through unusual conditions. John Morgan, an instrument maker in London, set aside the rules and took him in to be his apprentice on the condition that Watt would be given only a meager salary. (http://www.egr.msu.
edu/~lira/supp/steam/wattbio.html)With John Morgan, Watt learned the skills of instrument-making. John Morgan was impressed with Watt that he agreed to shorten the period of apprenticeship from the required period of seven-years to a period of one year. Watt took the offer in 1755. (http://www.egr.msu.edu/~lira/supp/steam/wattbio.
html)Watt worked with vigor and passion. He was so devoted with his goal to be an instument-maker that he spent much of his time working and learning the art of instrument-making. During the period of his apprenticeship with John Morgan, Watt was able to surpass the skills of the official apprentice who was already working there for two years. He was so dedicated with his job that he worked 10 hours a day. After hours, he worked for a small amount of cash because the wage he received as an apprentice was not enough.
(Porter, Ogilve, 2000)Watt’s health deteriorated because he spent long hours working with only a small amount of food. During this time, Britain was at war with France, and the military would force into service any able-bodied men. Watt avoided the streets for this reason and this contributed to the further deterioration of his health. Yet he persevered and was able to finish his apprenticeship until illness forced him to return to Greenock in 1756. (http://www.egr.msu.
edu/~lira/supp/steam/wattbio.html)After recovery, he set up a business as an instrument maker in Glasgow, but found that the other instrument makers shunned his credentials and training. However, the university professors recognized his abilities and encouraged him to work in the university. They agreed for Watt to set up a shop within its grounds and they created the position, “Mathematical Instrument Maker to the University. (http://www.egr.msu.
edu/~lira/supp/steam/wattbio.html)In 1757, he worked in Glasgow University where he proudly described himself as “Instrument Maker to Glasgow University. (Porter, Ogilve, 2000)It was in this period that he developed the steam engine.During the Industrial Revolution in the years 1760 to 1830, the economy of most part of Europe changed and the progress of developing technology accelerated.
Technology was at the core of everything. The period was overflowing with engineers, mechanics, millwrights, and dexterous and imaginative tinkers who spent their time and energy designing better pumps, pulleys, pendulums, and other simple machines. It was at this time that the most famous invention during the Industrial Revolution was invented: the steam engine. (http://www.
newworldencyclopedia.org/entry/James_Watt)The first steam engine prototype was built by a Frenchman named Denis Papin, but the first useful atmospheric steam engine was built in 1712 by a Cornish mechanic named Thomas Newcomen. Newcomen’s invention was used in Britain for almost half a century. The machine, however, was noisy and it used too much fuel.
(www.us.oup.com/us/pdf/economic.history/industrial.pdf)One day in 1763, Professor John Anderson, a professor in the university, approached James Watt and showed him a lab-scale model of the Newcomen pump to investigate why the model required so much steam. The model would stall after a few pumps.
The machine proved to be temperamental and difficult to operate without air entering the cylinder and destroying the vacuum. He required Watt to repair the engine. (http://www.egr.msu.edu/~lira/supp/steam/wattbio.html)Watt set on to investigate the problem. He discovered that the flaw was due to an undersized boiler that could not provide enough steam to reheat the cylinder after a few strokes.
Aside from that, the Newcomen engine was inefficient, slow, and too costly. (Porter, Ogilve, 2000)The Newcomen pumps required such vast quantities of steam since they were cooled during every stroke, then reheated. The steam in the cylinder was condensed by a jet of water, thus creating a vacuum that, in turn, was filled during the power stroke by the atmosphere pressing the piston to the bottom of the cylinder. On each stroke the cylinder was heated by the steam and cooled by the injected water, thus absorbing a tremendous amount of heat. (Porter, Ogilve, 2000)Watt needed a way to condense the steam without cooling the cylinder. The idea did not come to him overnight, it took him months to arrange his plans and to experiment.
However, it was during one of his Sunday afternoon walks when the inspiration got to him. Watt later described the moment of inspiration:”I had gone to take a walk on a fine Sabbath afternoon, early in 1765. I had entered the green by the gate at the foot of Charlotte Street and had passed the old washing-house.
I was thinking upon the engine at the time, and had gone as far as the herd’s house, when the idea came into my mind that as steam was an elastic body it would rush into a vacuum, and if a communication were made between the cylinder and an exhausted vessel it would rush into it, and might be there condensed without cooling the cylinder. I then saw that I must get rid of the condensed steam and injection-water if I used a jet as in Newcomen’s engine. Two ways of doing this occurred to me. First, the water might be run off by a descending pipe, if an offlet could be got at the depth of thirty-five or thirty-six feet, and any air might be extracted by a small pump. The second was to make the pump large enough to extract both water and air. .
. . I had not walked farther than the golf-house when the whole thing was arranged in my mind.” (http://www.egr.msu.edu/~lira/supp/steam/wattbio.html)Watt was able to solve the problem of the Newcomen engine.
He made a separate condenser, with this, he could keep the cylinder hot, and the condenser fairly cold by lagging, thus improving the thermal efficiency of the machine and the economics of its operation. (Porter, Ogilve, 2000)He introduced a number of famous improvements to the steam engine until he was able to effectively make a different model, such as a separate condenser, the principle of double-acting expansion, improved gears, and regulators. Watt turned steam power from an atmospheric pump to a true steam engine. (www.us.
oup.com/us/pdf/economic.history/industrial.pdf)Watt’s University friends introduced him to John Roebuck, an industrialist who held leases on coal deposits. Roebuck agreed to back the development of a full-scale engine after he saw the model work. He would finance the development of the engine.
Watt developed a full-scale model which Roebuck used in his coal mine. However, the progress in developing the engine was slow because Roebuck did not employ machinists who were competent enough to do the job. (http://www.egr.msu.edu/~lira/supp/steam/wattbio.
html)In 1767, Watt traveled to England to acquire a patent for his engine with his Roebuck. The patent was granted in 1769. (http://www.egr.msu.edu/~lira/supp/steam/wattbio.html)On his way to Scotland, he met Matthew Boulton. Boulton was a major manufacturer in Birmingham and had the financial capacity to exploit Watt’s engine.
Eventually, Boulton was able to buy out Roebuck and he began manufacturing the engine. Meanwhile, Watt moved to Birmingham and made his living as a canal surveyor from 1767 and 1774. Although he was successful at this, his health suffered, and so he joined Boulton in his shop.
(Porter, Ogilve, 2000)From 1775, Boulton and Watt formed a partnership. Boulton manufactured Watt’s engines at the Soho Foundry, near Birmingham. Boulton hired highly skilled craftsmen who helped them develop the engine. They called the engine, Boulton-Watt engine.
html)The engine was then used in mines. The Boulton-Watt engines became a success. Pumps were installed in mines and Watt became busy maintaining business at Cornwall mines.(http://www.egr.msu.edu/~lira/supp/steam/wattbio.
html)Over the next several years, Watt introduced further improvements on the design until it became more efficient than its predecessor.He developed a double acting engine. At age 45, Watt developed his next great invention. The invention was the sun and planet gear system. By means of a mechanical linkage known as the ‘parallel motion’ and an extra set of valves, the engine was made to drive on both the forward and the background strokes of the piston, and the sun and planet gear system permitted the rotative wheel to turn more than once per stroke of the piston This engine was quickly used by cotton and wooden mills. (http://www.
html)He was able to acquire the patents of the double-acting engine and the sun and planet gear system in 1781 and 1782. (http://www.egr.msu.edu/~lira/supp/steam/wattbio.
html)Between 1775 and 1790, Watt made other inventions. He invented an automatic centrifugal governor, which cut off the steam when the engine began to work too quickly and turned it on again when it had slowed sufficiently. He also devised the steam indicator which shows the steam pressure and degree of vacuum within a cylinder. He also invented a way of copying letters and drawings. (http://www.egr.msu.
edu/~lira/supp/steam/wattbio.html)In 1782 a sawmill ordered an engine that was to replace 12 horses. In determining the price of his steam engines, Watt rated his engines in horsepower. After many experiments, he concluded that a horsepower was equivalent to 15,000kg/33,000 lb raised through 0.3m/ft each minute.
This method of describing the capability of the engine continued until recent years. (http://www.egr.
msu.edu/~lira/supp/steam/wattbio.html)In 1785, Watt was elected a fellow of the Royal Society. During the last decade of the 18th century, the active management of the Soho Works was taken over by Boulton and Watt’s sons, and in 1800, when the patent rights to the engine expired, Watt retired from the business but he continued designing and constructing copying machines. (Porter, Ogilve, 2000)Watt died on August 25, 1819 at the age of 83, leaving the legacy of highly useful machines. His original steam engine of 1765 is now in the Science Musem in London. His name has become immortalized as the unit of power; a watt is one joule per second, and one horsepower is equivalent to about 746 watts. (Porter, Ogilve, 2000)