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Nov 18, 2014
CHARLES BABBAGESUMIRAN ADHIKARI CLASS: IX A ROLL:24
CONTENTS1Birth 2Education 3Marriage, family, death 4Design of computers
4.1Difference engine 4.1.1Completed models 4.2Analytical engine 4.3Modern adaptations
Charles Babbage,FRS(26 December 1791 18 October 1871)was anEnglish mathematician,philosopher,inventorandmechanical engineerwho originated the concept of a programmablecomputer. Parts of his uncompleted mechanisms are on display in the London Science Museum. In 1991, a perfectly functioningdifference enginewas constructed from Babbage's original plans. Built to tolerances achievable in the 19th century, the success of the finished engine indicated that Baabbage's machine would have worked. Nine years later, the Science Museum completed theprinterBabbage had designed for the difference engine, an astonishingly complex device for the 19th century. Considered a "father of the computer", Babbage is credited with inventing the first mechanical computer that eventually led to more complex designs.
BIRTHBabbage's birthplace is disputed, but he was most likely born at 44 Crosby Row, Walworth Road, London, England. A blue plaque on the junction of Larcom Street and Walworth Road commemorates the event. His date of birth was given in his obituary inThe Timesas 25 December 1792. However after the obituary appeared, a nephew wrote to say that Charles Babbage was born one year earlier, in 1791. Theparish registerof St. Mary'sNewington, London, shows that Babbage wasbaptizedon 6 January 1792, supporting a birth year of 1791. Babbage's father, Benjamin Babbage, was a banking partner of the Praeds who owned the Bitton Estate inTeignmouth. His mother was Betsy Plumleigh Teape. In 1808, the Babbage family moved into the old Rowdens house inEast Teignmouth, and Benjamin Babbage became a warden of the nearby St. Michaels Church.
His father's money allowed Charles to receive instruction from several schools and tutors during the course of his elementary education. Around the age of eight he was sent to a country school in AplingtonnearExeterto recover from a lifethreatening fever. His parents ordered that his "brain was not to be taxed too much" and Babbage felt that "this great idleness may have led to some of my childish reasonings." For a short time he attended King Edward VI Grammar School inTotnes,South Devon, but his health forced him back to private tutors for a time. He then joined a 30-student Holmwood academy, in Baker Street, Enfield, Middlesex under Reverend Stephen Freeman. The academy had a well-stocked library that prompted Babbage's love of mathematics. He studied with two more private tutors after leaving the academy. Of the first, a clergyman nearCambridge, Babbage said, "I fear I did not derive from it all the advantages that I might have done." The second was an Oxford tutor from whom Babbage learned enough of the Classics to be accepted to Cambridge. Babbage arrived atTrinity College, Cambridgein October 1810.] He had read extensively inLeibniz,Joseph Louis Lagrange,Thomas Simpson, andLacroixand was seriously disappointed in the mathematical instruction available at Cambridge. In response, he,John Herschel,George Peacock, and several other friends formed theAnalytical Societyin 1812. Babbage, Herschel and Peacock were also close friends with future judge and patron of scienceEdward Ryan. Babbage and Ryan married two sisters. In 1812 Babbage transferred toPeterhouse, Cambridge.He was the top mathematician at Peterhouse, but did not graduate with honours. He instead received an honorary degree without examination in 1814.
Grave of Charles Babbage atKensal Green Cemetery
Marriage, Family, Death
On 25 July 1814, Babbage married Georgiana Whitmore at St. Michael's Church in Teignmouth, Devon. The couple lived atDudmaston Hall,[ Shropshire (where Babbage engineered the central heating system), before moving to 5 Devonshire Street, Portland Place, London. Charles and Georgiana had eight children,but only three Benjamin Herschel, Georgiana Whitmore, and Henry Prevost survived to adulthood. Georgiana died inWorcesteron 1 September 1827. Charles' father, wife, and at least one son all died in 1827. These deaths caused Babbage to go into a mental breakdown which delayed the construction of his machines. His youngest son, Henry Prevost Babbage (18241918), went on to create six working difference engines based on his father's designs,one of which was sent toHarvard Universitywhere it was later discovered byHoward H. Aiken, pioneer of theHarvard Mark I. Henry Prevost's 1910 Analytical Engine Mill, previously on display atDudmaston Hall, is now on display atthe Science Museum. Charles Babbage died at age 79 on 18 October 1871, and was buried in London'sKensal Green Cemetery. According to Horsley, Babbage died "of renal inadequacy, secondary tocystitis. In 1983 the autopsy report for Charles Babbage was discovered and later published by one of his descendants.A copy of the original is also available.Half of Babbage's brain is preserved atthe Hunterian Museum in the Royal College of Surgeonsin London
Part of Babbage's difference engine, assembled after his death by Babbage's son, using parts found in his laboratory.
Design of computers
This sectionmay containoriginal research. Pleaseimprove itbyverifyingthe claims made and addingreferences. Statements consisting only of original research may be removed. Babbage sought a method by which mathematical tables could be calculated mechanically, removing the high rate of human error. Three different factors seem to have influenced him: a dislike of untidiness; his experience working onlogarithmic tables; and existing work on calculating machines carried out byWilhelm Schickard,Blaise Pascal, andGottfried Leibniz. He first discussed the principles of a calculating engine in a letter to SirHumphry Davyin 1822. Part of Babbage's difference engine, assembled after his death by Babbage's son, using parts found in his laboratory. Babbage's machines were among the first mechanical computers, although they were not actually completed, largely because of funding problems and personality issues. He directed the building of some steam-powered machines that achieved some success, suggesting that calculations could be mechanized. Although Babbage's machines were mechanical and unwieldy, their basic architecture was very similar to a modern computer. The data and program memory were separated, operation was instruction based, the control unit could make conditional jumps and the machine had a separateI/Ounit.
TheLondon Science Museum'sDifference Engine , built from Babbage's design.
In Babbages time, numerical tables were calculated by humans who were called computers, meaning "one who computes", much as a conductor is "one who conducts". At Cambridge, he saw the high error-rate of this human-driven process and started his lifes work of trying to calculate the tables mechanically. He began in 1822 with what he called the difference engine, made to compute values of polynomial functions. Unlike similar efforts of the time, Babbage's difference engine was created to calculate a series of values automatically. By using the method offinite differences, it was possible to avoid the need for multiplication and division. TheLondon Science Museum's Difference Engine #2, built from Babbage's design. The first difference engine was composed of around 25,000 parts, weighed fifteentons(13,600kg), and stood 8ft (2.4m) high. Although he received ample funding for the project, it was never completed. He later designed an improved version, "Difference Engine No. 2", which was not constructed until 1989-1991, using Babbage's plans and 19th century manufacturing tolerances. It performed its first caalculation at the London Science Museum returning results to 31 digits, far more than the average modern pocket calculator. Completed models The London Science Museum has constructed two Difference Engines, according to Babbage's plans for the Difference Engine No 2. One is owned by the museum; the other, owned by technology millionaireNathan Myhrvold, went on exhibit at theComputer History MuseuminMountain View, Californiaon 10 May 2008.The two models that have been constructed are not replicas; until the assembly of the first Difference Engine No 2 by the London Science Museum, no model of the Difference Engine No 2 existed
ANALYTICAL ENGINESoon after the attempt at making the difference engine crumbled, Babbage started designing a different, more complex machine called the Analytical Engine. The engine is not a single physical machine but a succession of designs that he tinkered with until his death in 1871. The main difference between the two engines is that the Analytical Engine could be programmed usingpunch cards. He realized that programs could be put on these cards so the person had only to create the program initially, and then put the cards in the machine and let it run. The analytical engine would have used loops ofJacquard'spunched cards to control a mechanical calculator, which could formulate results based on the results of preceding computations. This machine was also intended to employ several features subsequently used in modern computers, including sequential control, branching, and looping, and would have been the first mechanical device to beTuring-complete.
Ada Lovelace, an impressive mathematician, and one of the few people who fully understood Babbage's ideas, created a program for the Analytical Engine. Had the Analytical Engine ever actually been built, her program would have been able to calculate a sequence ofBernoulli numbers. Based on this work, Lovelace is now widely credited with being the firstcomputer programmer.[In 1979, a contemporary programming language was na