James Watt (19 January 1736 19 August 1819) was a Scottish mathematician and engineer. He did not invent the first steam engine, but he did modify it to work better. There were other patented steam engines (such as the Savery and Newcomen steam engines) in use by the time Watt started his work on them. His major contribution is in developing the modern form of the steam engine. The Watt steam engine is credited for driving the Industrial Revolution of the 18th and 19th centuries. James Watt was a brilliant engineer and he also transformed the Newcomen engine.
Today, most people honor him by naming a unit of power, the watt, after him.
James Watt was born on 19 January 1736 in Greenock, Renfrewshire. His father was a shipwright, ship owner and contractor, and served as the town's chief baillie. His mother, Agnes Muirhead, came from a distinguished family and was well educated. Both were Presbyterians and strong Covenanters. Watt's grandfather, Thomas Watt, taught mathematics and was a baillie to the Baron of Cartsburn. Watt did not go to school every day. At first, he was mostly schooled at home by his mother but later he attended Greenock grammar school. He exhibited great skill with his hands and a natural ability for mathematics, although Latin and Greek failed to interest him. He also absorbed the legends and lore of the Scottish people.
One of Watt's many improvements was the invention of a "centrifugal governor" to regulate automatically the speed of the engine. This is most obvious on steam engines where it regulates the admission of steam into the cylinder(s). It is also found on internal combustion engines and variously fueled turbines, and in some modern striking clocks.
A centrifugal governor is a homeostatic device which controls the speed of an engine by regulating the amount of "intermediate substance" (steam) which drives the machine. This keeps a near constant speed whatever the load or fuel supply conditions. It uses the principle of proportional control: this means the stopping of (in this case) steam varies according to the speed of the machine.
On Watt's fly-ball device, as the machine speeds up, the balls fly round faster. As they fly round faster, they move out from the central post. As they move out from the central post, they close the steam supply more firmly. As they do so, the machine slows down and the balls spin more slowly, and allow more steam into the cylinders. In addition, the system has a safety release valve to allow excess steam to escape without driving the wheels. 500 Boulton & Watt engines were built by the firm between 1775 and 1800.
Later, this kind of feedback loop became an important tool of cybernetics.
Watt went into partnership with a fellow member of the Midlands Lunar Society, Matthew Boulton. The firm of Boulton & Watt designed and built steam engines, and was very important in the Industrial Revolution.
At first the partnership made the drawing and specifications for the engines, and supervised the work to erect it on the customer's 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 make 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. There they built a new foundry for making the engines. The Soho Foundry 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 forty-one engines.
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 Jr. Longtime firm engineer William Murdoch was soon made a partner and the firm prospered.
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Michelangelo
Michelangelo di Lodovico Buonarroti Simoni (6 March 1475 – 18 February 1564), known as Michelangelo, was an Italian Renaissance painter, sculptor, architect, poet, and engineer. Along with Leonardo da Vinci, he is often called a "Renaissance Man" which means that he had great talent in many areas.
Michelangelo lived an extremely busy life, creating a great number of artworks. Some of Michelangelo's works are among the most famous that have ever been made. They include two very famous marble statues, "the Pieta" in Saint Peter's Basilica and "David" which once stood in a plazza in Florence but is now in the Accademia Gallery. His most famous paintings are huge frescos, the Sistine Chapel Ceiling and the "Last Judgement". His most famous work of architecture is the east end and dome of Saint Peter's Basilica.
A lot is known about Michelangelo's life because he left many letters, poems and journals. Because he was so famous, he became the very first artist to have his biography (story of his life) published while he was still living. His biographer, Giorgio Vasari, said that he was the greatest artist of the Renaissance. He was sometimes called "Il Divino" ("the divine one").
Other artists said that he had "terribilità", (his works were so grand and full of strong emotion that they were scary). Many other artists who saw his work tried to have the same emotional quality. From this idea of "terribilità" came a style of art called Mannerism.
Michelangelo was born on 6 March 1475 in Caprese near Arezzo, Tuscany. His father was Lodovico di Leonardo di Buonarroti di Simoni, and his mother was Francesca di Neri del Miniato di Siena. The Buonarrottis were a banking family from Florence. They claimed they were descended from the noble Countess Matilda of Canossa. Michelangelo's father had lost most of the bank’s money, so he worked for the local government in the town of Chiusi. When Michelangelo was a baby, the family moved back to Florence. As he was sickly, Michelangelo was sent to live on a small farm with a stonecutter and his wife and family. The stonecutter worked at a marble quarry owned by Michelangelo's father. Many years later Michelangelo said that the two things that had helped him to be a good artist were being born in the gentle countryside of Arezzo and being raised in a house where, along with his nurse's milk, he was given the training to use a chisel and hammer. His mother died when he was only six.
Michelangelo’s father then brought him back to Florence and sent him to study with a tutor, Francesco da Urbino. Michelangelo was not interested in his school lessons. He explored the great churches of the city and drew copies of the frescos that he saw there. When he was thirteen, he was apprenticed to the painter Domenico Ghirlandaio. Ghirlandaio had a large busy studio. He had rich patrons who worked for the Medici. He painted frescos in their family chapels. Michelangelo was able to learn the art of fresco painting very well, from Ghirlandaio. In a large workshop such as Ghirlandaio’s, artists would have been working in all sorts of different media, including sculpture, metalwork and painting altarpieces. Michelangelo would have learned about all these things. When Michelangelo was only fourteen, his father persuaded Ghirlandaio to pay his apprentice as an artist, which was highly unusual at the time.