Charles Babbage

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Charles Babbage

Sketch by Henri Claude, 1860s[1] Born Died Nationality Fields

26 December 1791 London, England 18 October 1871 (aged 79) Marylebone, London, England United Kingdom Mathematics, analytic philosophy, computer science

Institutions

Trinity College, Cambridge

Alma mater

Peterhouse, Cambridge

Known for

Mathematics, computing

Religious stance Christian

Charles Babbage, FRS (26 December 1791 – 18 October 1871)[2] was an English mathematician, philosopher, inventor and mechanical engineer who originated the concept of a programmable computer. Parts of his uncompleted mechanisms are on display in the London Science Museum. In 1991, a perfectly functioning difference engine was constructed from Babbage's original plans. Built to tolerances achievable in the 19th century, the success of the finished engine indicated that Babbage's machine would have worked. Nine years later, the Science Museum completed the printer Babbage had designed for the difference engine, an astonishingly complex device for the 19th century. Considered a "father of the computer"[3]

Babbage is credited with inventing the first mechanical computer that eventually led to more complex designs.

Contents [hide]

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1 Birth 2 Education 3 Marriage, family, death 4 Design of computers o 4.1 Difference engine  4.1.1 Completed models o 4.2 Analytical engine o 4.3 Modern adaptations 5 Other accomplishments 6 Eccentricities 7 Quotations 8 Commemoration 9 Publications 10 References

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11 External links

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[edit] Birth The birthplace of Charles Babbage is still disputed, but he was most likely born in 44 Crosby Row, Walworth Road, London, England. A blue plaque on the junction of Larcom Street and Walworth Road commemorates the event. Babbage's date of birth was given in his obituary in The Times as 25 December 1792. However after the obituary appeared, a nephew wrote to say that Charles Babbage actually was born one year earlier, in 1791. The parish register of St. Mary's Newington, London, shows that Babbage was baptized on 6 January 1792, supporting a birth year of 1791.[4][5][6] Charles' father, Benjamin Babbage, was a banking partner of the Praeds who owned the Bitton Estate in Teignmouth. His mother was Betsy Plumleigh Teape. In 1808, the Babbage family moved into the old Rowdens house in East Teignmouth, and Benjamin Babbage became a warden of the nearby St. Michael’s Church.

[edit] Education Wikisource has original text related to this article: The Times/The Late Mr. Charles Babbage, F.R.S.

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 Alphington near Exeter to recover from a life-threatening 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 in Totnes, South Devon, but his health forced him back to private tutors for a time.[7] 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 near Cambridge, 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 at Trinity College, Cambridge in October 1810.[8] He had read extensively in Leibniz, Joseph Louis Lagrange, Thomas Simpson, and Lacroix and was seriously disappointed in the mathematical instruction available at Cambridge. In response, he, John Herschel, George Peacock, and several other friends formed the Analytical Society in 1812. Babbage, Herschel and Peacock were also close friends with future judge and patron of science Edward Ryan. Babbage and Ryan married two sisters.[9] In 1812 Babbage transferred to Peterhouse, Cambridge.[8] He was the top mathematician at Peterhouse, but did not graduate with honours. He instead received an honorary degree without examination in 1814.

[edit] Marriage, family, death

Grave of Charles Babbage at Kensal Green Cemetery On 25 July 1814, Babbage married Georgiana Whitmore at St. Michael's Church in Teignmouth, Devon. The couple lived at Dudmaston Hall,[10] Shropshire (where Babbage engineered the central heating system), before moving to 5 Devonshire Street, Portland Place, London. Charles and Georgiana had eight children,[11] but only three — Benjamin Herschel, Georgiana Whitmore, and Henry Prevost — survived to adulthood. Georgiana died in Worcester on 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 (1824-1918), went on to create six working difference engines based on his father's designs,[12] one of which was sent to Harvard University where it

was later discovered by Howard H. Aiken, pioneer of the Harvard Mark I. Henry Prevost's 1910 Analytical Engine Mill, previously on display at Dudmaston Hall, is now on display at the Science Museum.[13] Charles Babbage died at age 79 on 18 October 1871, and was buried in London's Kensal Green Cemetery. According to Horsley, Babbage died "of renal inadequacy, secondary to cystitis."[14] In 1983 the autopsy report for Charles Babbage was discovered and later published by one of his descendants.[15][16] A copy of the original is also available.[17] Half of Babbage's brain is preserved at the Hunterian Museum in the Royal College of Surgeons in London.[18][19]

[edit] Design of computers 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 on logarithmic tables; and existing work on calculating machines carried out by Wilhelm Schickard, Blaise Pascal, and Gottfried Leibniz. He first discussed the principles of a calculating engine in a letter to Sir Humphry Davy in 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 separate I/O unit.

[edit] Difference engine Main article: Difference engine In Babbage’s 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 life’s 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 of finite differences, it was possible to avoid the need for multiplication and division.

The London Science Museum's Difference Engine #2, built from Babbage's design. The first difference engine was composed of around 25,000 parts, weighed fifteen tons (13,600 kg), and stood 8 ft (2.4 m) 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 calculation at the London Science Museum returning results to 31 digits, far more than the average modern pocket calculator. [edit] 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 millionaire Nathan Myhrvold, went on exhibit at the Computer History Museum[20] in Mountain View, California on 10 May 2008.[21] It remained there until April 2009, after which it was moved to Myhrvold's personal collection.[22] 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.

[edit] Analytical engine Main article: Analytical engine Soon 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 using punch 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 of Jacquard's punched 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 be Turing-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 of Bernoulli numbers. Based on this work, Lovelace is now widely credited with being the first computer programmer.[23] In 1979, a contemporary programming language was named Ada in her honour. Shortly afterward, in 1981, a satirical article by Tony Karp in the magazine Datamation described the Babbage programming language as the "language of the future".[24]

[edit] Modern adaptations While the abacus and mechanical calculator have been replaced by electronic calculators using microchips, the recent advances in MEMS and nanotechnology have led to recent high-tech experiments in mechanical computation. The benefits suggested include operation in high radiation or high temperature environments.[25] These modern versions of mechanical computation were highlighted in the magazine The Economist in its special "end of the millennium" black cover issue in an article entitled "Babbage's Last Laugh".[26] The article highlighted work done at University of California Berkeley by Ezekiel Kruglick. In this Doctoral Dissertation[27] the researcher reports mechanical logic cells and architectures sufficient to implement the Babbage Analytical engine (see above) or any general logic circuit. Carry-shift digital adders and various logic elements are detailed as well as modern analysis on required performance for microscopic mechanical logic.

[edit] Other accomplishments In 1824, Babbage won the Gold Medal of the Royal Astronomical Society "for his invention of an engine for calculating mathematical and astronomical tables." He was a founding member of the society and one of its oldest living members on his death in 1871. From 1828 to 1839 Babbage was Lucasian Professor of Mathematics at Cambridge. He contributed largely to several scientific periodicals, and was instrumental in founding the Astronomical Society in 1820 and the Statistical Society in 1834. However, he dreamt of designing mechanical calculating machines. “... I was sitting in the rooms of the Analytical Society, at Cambridge, my head leaning forward on the table in a kind of dreamy mood, with a table of logarithms lying open before me. Another member, coming into the room, and seeing me half asleep, called out, "Well, Babbage, what are you dreaming about?" to which I replied "I am thinking that all these tables" (pointing to the logarithms) "might be calculated by machinery. " In 1837, responding to the Bridgewater Treatises, of which there were eight, he published his Ninth Bridgewater Treatise, "On the Power, Wisdom and Goodness of God, as manifested in the Creation", putting forward the thesis that God had the omnipotence and foresight to create as a divine legislator, making laws (or programs) which then produced species at the appropriate times, rather than continually interfering with ad hoc miracles each time a new species was

required. The book is a work of natural theology, and incorporates extracts from correspondence he had been having with John Herschel on the subject. Babbage also achieved notable results in cryptography. He broke Vigenère's autokey cipher as well as the much weaker cipher that is called Vigenère cipher today. The autokey cipher was generally called "the undecipherable cipher", though owing to popular confusion, many thought that the weaker polyalphabetic cipher was the "undecipherable" one. Babbage's discovery was used to aid English military campaigns, and was not published until several years later; as a result credit for the development was instead given to Friedrich Kasiski, a Prussian infantry officer, who made the same discovery some years after Babbage.[28] In 1838, Babbage invented the pilot (also called a cow-catcher), the metal frame attached to the front of locomotives that clears the tracks of obstacles. He also constructed a dynamometer car and performed several studies on Isambard Kingdom Brunel's Great Western Railway in about 1838.[29] Babbage's eldest son, Benjamin Herschel Babbage, worked as an engineer for Brunel on the railways before emigrating to Australia in the 1850s[30] Babbage also invented an ophthalmoscope, but although he gave it to a physician for testing it was forgotten, and the device only came into use after being independently invented by Hermann von Helmholtz.[31] Babbage twice stood for Parliament as a candidate for the borough of Finsbury. In 1832 he came in third among five candidates, but in 1834 he finished last among four.[32][33][34] In On the Economy of Machine and Manufacture, Babbage described what is now called the Babbage principle, which describes certain advantages with division of labour. Babbage noted that highly skilled - and thus generally highly paid - workers spend parts of their job performing tasks that are 'below' their skill level. If the labour process can be divided among several workers, it is possible to assign only high-skill tasks to high-skill and -cost workers and leave other working tasks to less-skilled and paid workers, thereby cutting labour costs. This principle was criticised by Karl Marx who argued that it caused labour segregation and contributed to alienation. The Babbage principle is an inherent assumption in Frederick Winslow Taylor's scientific management.

[edit] Eccentricities •

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Babbage once counted all the broken panes of glass of a factory, publishing in 1857 a "Table of the Relative Frequency of the Causes of Breakage of Plate Glass Windows": Of 464 broken panes, 14 were caused by "drunken men, women or boys".[35][36][37] Babbages's distaste for commoners ("the Mob") included writing "Observations of Street Nuisances" in 1864, as well as tallying up 165 "nuisances" over a period of 80 days. He especially hated street music, and in particular the music of organ grinders, against whom he railed in various venues. The following quotation is typical:

It is difficult to estimate the misery inflicted upon thousands of persons, and the absolute pecuniary penalty imposed upon multitudes of intellectual workers by the loss of their time, destroyed by organ-grinders and other similar nuisances.[38] •

Babbage once contacted the poet Alfred Tennyson in response to his poem "The Vision of Sin". Babbage wrote, "In your otherwise beautiful poem, one verse reads, Every moment dies a man, Every moment one is born. ... If this were true, the population of the world would be at a standstill. In truth, the rate of birth is slightly in excess of that of death. I would suggest [that the next version of your poem should read]: Every moment dies a man, Every moment 1 1/16 is born. Strictly speaking, the actual figure is so long I cannot get it into a line, but I believe the figure 1 1/16 will be sufficiently accurate for poetry."[39]

[edit] Quotations On two occasions I have been asked, – "Pray, Mr. Babbage, if you put into the machine wrong figures, will the right answers come out?" In one case a member of the Upper, and in the other a member of the Lower House put this question. I am not able rightly to apprehend the kind of confusion of ideas that could provoke such a question.[40]

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[edit] Commemoration Babbage has been commemorated by a number of references, as shown on this list. In particular, the crater Babbage on the Moon, and the Charles Babbage Institute, an information technology archive and research center at the University of Minnesota, were named after him. The large Babbage lecture theatre at Cambridge University, used for undergraduate science lectures, commemorates his time at the university. • • • • •

British Rail named a locomotive after him in the 1990s as part of a program of naming locomotives after famous and significant scientists. The University of Plymouth commemorates Charles Babbage with the Babbage building, the University's school of computing is based here. Also, in Monk's Walk School, there is a block called "Babbage" to commemorate his work in the world of science. In Chessington, in the Royal Borough of Kingston upon Thames, a road in a new housing development has been named Charles Babbage Close. The Babbage programming language for GEC 4000 series minicomputers is named after him.

[edit] Publications

Wikisource has original works written by or about: Charles Babbage Wikimedia Commons has media related to: Charles Babbage

Wikisource has the text of the 1911 Encyclopædia Britannica article Babbage, Charles. •

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Babbage, Charles (1826). A Comparative View of the Various Institutions for the Assurance of Lives. London: J. Mawman. http://books.google.com/books?id=teGjS4XfpbMC&printsec=frontcover&dq=charles+ba bbage&as_brr=1#PPR1,M2. Babbage, Charles (1830). Reflections on the Decline of Science in England, and on Some of Its Causes. London: B. Fellowes. http://books.google.com/books?id=3bgPAAAAMAAJ&printsec=frontcover&dq=charles +babbage&as_brr=1#PPR1,M2. Babbage, Charles (1835). On the Economy of Machinery and Manufactures (4 ed.). London: Charles Knight. http://books.google.com/books?id=wUQeMa0MFnkC&printsec=frontcover&dq=charles +babbage&as_brr=1#PPR1,M2. Babbage, Charles (1837). The Ninth Bridgewater Treatise, a Fragment. London: John Murray. http://books.google.com/books?id=RlgEAAAAQAAJ&printsec=frontcover&dq=charles +babbage&as_brr=1#PPP7,M2. Babbage, Charles (1841). Table of the Logarithms of the Natural Numbers from 1 to 108000. London: William Clowes and Sons. http://books.google.com/books?id=teMGAAAAYAAJ&printsec=frontcover&dq=charles +babbage&as_brr=1#PPT8,M2. Babbage, Charles (1851). The Exposition of 1851. London: John Murray. http://books.google.com/books?id=NZcBAAAAQAAJ&printsec=frontcover&dq=charles +babbage&as_brr=1#PPR3,M2. Babbage, Charles (1864). Passages from the Life of a Philosopher. London: Longman. http://books.google.com/books?id=2T0AAAAAQAAJ&printsec=frontcover&dq=charles +babbage&as_brr=1#PPR3,M2.

[edit] References 1. ^ "NPG Ax18347". Npg.org.uk.

http://www.npg.org.uk/live/search/portrait.asp?LinkID=mp00196&rNo=3. Retrieved on 2009-01-29. 2. ^ GRO Register of Deaths: December 1871 1a 383 MARYLEBONE - Charles Babbage, aged 79 3. ^ Halacy, Daniel Stephen (1970). Charles Babbage, Father of the Computer. CrowellCollier Press. ISBN 0027413705. Others can be regarded as having a claim on this title, such as John Vincent Atanasoff or Alan Turing. 4. ^ Hyman, Anthony (1982). Charles Babbage, Pioneer of the Computer. Princeton University Press. p. 5. 5. ^ Moseley, Maboth (1964). Irascible Genius, The Life of Charles Babbage. Chicago: Henry Regnery Company. p. 29. 6. ^ "The Late Mr. Charles Babbage, F.R.S.". The Times. 7. ^ Moseley, Maboth (1964). Irascible Genius, The Life of Charles Babbage. Chicago: Henry Regnery Company. p. 39. 8. ^ a b Babbage, Charles in Venn, J. & J. A., Alumni Cantabrigienses, Cambridge University Press, 10 vols, 1922–1958. 9. ^ Wilkes (2002) p.355 10. ^ "Attraction information for Dudmaston Hall: VisitBritain". VisitBritain. http://www.visitbritain.co.uk/Attraction/Bridgnorth/Historic-House-orPalace/157092/Dudmaston-Hall.htm. Retrieved on 2009-01-29. 11. ^ Valerie Bavidge-Richardson. "Babbage Family Tree 2005". http://www.bavidge.co.uk/Babbage%20Family%20Tree%202005,%20InternetTree/wc03/ wc03_074.htm. Retrieved on 2007-10-22. 12. ^ "Henry Prevost Babbage - The Babbage Engine | Computer History Museum". Computerhistory.org. http://www.computerhistory.org/babbage/henrybabbage/. Retrieved on 2009-01-29. 13. ^ "Home – Henry Babbage's Analytical Engine Mill, 1910". Science Museum. 2007-0116. http://www.sciencemuseum.org.uk/objects/computing_and_data_processing/189658.aspx. Retrieved on 2009-01-29. 14. ^ Horsley, Victor (1909). "Description of the Brain of Mr. Charles Babbage, F.R.S". Philosophical Transactions of the Royal Society of London. Series B, Containing Papers of a Biological Character 200: 117–132. doi:10.1098/rstb.1909.0003. http://journals.royalsociety.org/content/xl7210623532p738/?p=daaddfe06dca444eafad36a ab95177ea&pi=1. Retrieved on 2007-12-07.- subscription required 15. ^ Babbage, Neville (June 1991). "Autopsy Report on the Body of Charles Babbage ("the father of the computer")". Medical Journal of Australia 154 (11): 758–9. PMID 2046574. 16. ^ Williams, Michael R. (1998). "The "Last Word" on Charles Babbage". IEEE Annals of the History of Computing 20: 10–4. doi:10.1109/85.728225. http://www2.computer.org/portal/web/csdl/doi/10.1109/85.728225. - subscription required 17. ^ "Postmortem report by John Gregory Smith, F.R.C.S. (anatomist)". Science and society.co.UK.

http://www.scienceandsociety.co.uk/results.asp?X9=BABBAGE,%20CHARLES. Retrieved on 2009-01-29. 18. ^ "Babbage's brain". Blogtobelet.blogspot.com. http://blogtobelet.blogspot.com/. Retrieved on 2009-01-29. 19. ^ "Babbage's brain". www.DanYEY.co.uk. http://www.danyey.co.uk/london.php. Retrieved on 2009-01-29. 20. ^ "Overview - The Babbage Engine | Computer History Museum". Computerhistory.org. http://www.computerhistory.org/babbage/. Retrieved on 2009-01-29. 21. ^ Shiels, Maggie. "Victorian 'supercomputer' is reborn". http://news.bbc.co.uk/2/hi/technology/7391593.stm. Retrieved on 2008-05-11. 22. ^ "The Babbage Engine – Computer History Museum". http://www.computerhistory.org/babbage/. Retrieved on 2008-09-26. 23. ^ Fuegi J, Francis J (October-December 2003). "Lovelace & Babbage and the creation of the 1843 'notes'". Annals of the History of Computing 25 (4): 16–26. doi:10.1109/MAHC.2003.1253887. See pages 19, 25 24. ^ Karp, Tony. "Babbage - The language of the future". http://www.tlcsystems.com/babbage.htm. Retrieved on 2008-05-11. 25. ^ "Electronics Times: Micro-machines are fit for space". Findarticles.com. 1999-10-11. http://findarticles.com/p/articles/mi_m0WVI/is_1999_Oct_11/ai_56912203/print. Retrieved on 2009-01-29. 26. ^ Babbage's Last Laugh (requires paid subscription) 27. ^ "Doctoral Dissertation". Bsac.eecs.berkeley.edu. http://wwwbsac.eecs.berkeley.edu/publications/search/zoom.php?urltimestamp=1042574398. Retrieved on 2009-01-29. 28. ^ Kahn, David L. (1996). The Codebreakers: The Story of Secret Writing. New York: Scribner. ISBN 978-0-684-83130-5. 29. ^ "Babbage, Charles - "Passages from the Life of a Philosopher", page 317-318.". http://books.google.com/books?id=2T0AAAAAQAAJ&printsec=frontcover&dq=charles +babbage&as_brr=1#PPR3,M2. 30. ^ "Babbage, Benjamin Herschel - Bright Sparcs Biographical entry". http://www.asap.unimelb.edu.au/bsparcs/biogs/P000074b.htm. Retrieved on 2008-05-15. 31. ^ "Medical Discoveries, Ophthalmoscope". Discoveriesinmedicine.com. http://www.discoveriesinmedicine.com/Ni-Ra/Ophthalmoscope.html. Retrieved on 200901-29. 32. ^ Crowther, J. G. (1968). Scientific Types. London: Barrie & Rockliff. p. 266. ISBN 0248997297. 33. ^ Hyman Anthony (1982). Charles Babbage, Pioneer of the Computer. Princeton, New Jersey: Princeton University Press. pp. 82–7. ISBN 0691083037. 34. ^ Moseley (1964). Irascible Genius, The Life of Charles Babbage. Chicago: Henery Regnery. pp. 120–1.- Note some confusion as to the dates. 35. ^ Babbage, Charles (1857). "Table of the Relative Frequency of Occurrence of the Causes of Breaking of Plate Glass Windows". Mechanics Magazine 66: 82. 36. ^ Babbage, Charles (1989). Martin Campbell-Kelly. ed. The Works of Charles Babbage. V. London: William Pickering. p. 137. ISBN 1851960058. 37. ^ See this web site for Babbage's table of causes of broken glass panes.

38. ^ Campbell-Kelly, Martin; Babbage, Charles (1994). "Ch 26". Passages from the Life of

a Philosopher. Pickering & Chatto Publishers. p. 342. ISBN 1-85196-040-6. 39. ^ Babbage, Charles; Swade, Doron (2001). The difference engine: Charles Babbage and

the quest to build the first computer. Ringwood, Vic: Viking Penguin. p. 77. ISBN 0-14200144-9.} 40. ^ Campbell-Kelly, Martin; Babbage, Charles (1994). "V Difference Engine No. 1". Passages from the Life of a Philosopher. Pickering & Chatto Publishers. p. 67. ISBN 185196-040-6.

[edit] External links • • • • • • • • •

Babbage at the Science Museum Charles Babbage Mr. Charles Babbage - obituary from The Times (1871) The Babbage Pages The Babbage Difference Engine - an overview of how it works. "On a Method of Expressing by Signs the Action of Machinery" , 1826. - Original edition Archival material relating to Charles Babbage listed at the UK National Register of Archives Charles Babbage at Find a Grave Charles Babbage Institute - pages on "Who Was Charles Babbage?" including biographical note, description of Difference Engine No. 2, publications by Babbage, archival and published sources on Babbage, sources on Babbage and Ada Lovelace.