Charles Babbage

Charles Babbage, FRS

Charles Babbage, FRS (December 26, 1791 London, England – October 18, 1871 Marylebone, London, England) 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. Babbage is credited with inventing the first mechanical computer that eventually led to more complex designs.


The birthplace of Charles Babbage is 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 December 26, 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 January 6, 1792, supporting a birth year of 1791.

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.


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. 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. 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. Ultimately, Babbage and Ryan married sisters.

In 1812 Babbage transferred to Peterhouse, Cambridge. He was the top mathematician at Peterhouse, but failed to graduate with honors. He instead received an honorary degree without examination in 1814.

Marriage, family, death

Grave of Charles Babbage at Kensal Green Cemetery

Grave of Charles Babbage at Kensal Green CemeteryOn July 25, 1814, Babbage married Georgiana Whitmore at St. Michael's Church in Teignmouth, Devon. The couple lived at Dudmaston Hall[8], 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 in Worcester on September 1, 1827. Charles' father, wife, and at least two sons 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, one of which was sent to 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.

Charles Babbage died at age 79 on October 18, 1871, and was buried in London's Kensal Green Cemetery. According to Horsley, Babbage died "of renal inadequacy, secondary to cystitis."[12] In 1983 the autopsy report for Charles Babbage was discovered and later published by one of his descendants.[13][14] A copy of the original is also available. Babbage's brain is preserved at the Science Museum in London.

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 engines 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.

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.

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 in Mountain View, California on 10 May 2008. It will remain there until April 2009, after which it will move to Myhrvold's personal collection. 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 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. 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".

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.

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". The article highlighted work done at University of California Berkeley by Ezekiel Kruglick. In this Doctoral Dissertation 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.

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.

Charles Babbage

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.

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. Babbage's eldest son, Benjamin Herschel Babbage, worked as an engineer for Brunel on the railways before emigrating to Australia in the 1850s

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.

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.

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.


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".

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.

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."


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.

Charles Babbage


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, 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.

Charles Babbage's Computer Engines

The Difference and Analytic Engines: precursors of modern computers. It took the wild mind of Charles Babbage to come up with it!

Mathematician and inventor Charles Babbage had already fallen out of favor with the British government and mathematical community before his death in 1871. He was a visionary, and like many visionaries, saw too far ahead of his time for his peers to fully comprehend or appreciate.

Babbage was born December 26, 1792, to a banker in Totnes, Devonshire, England. Babbage had many brothers and sisters, but most died before adulthood, and like them, he was sickly as a child. Even before his formal education began, he was a tinkerer. He loved to take mechanical things apart, and did little else with his toys besides dissect them.

Eventually Babbage was put in the care of a church school near Exeter, where the minister was told by his family to make sure that Babbage was healthy, rather than well-educated. Because of this concern, the minister didn't give Babbage enough work to keep him interested and occupied. Superstitious, despite a thorough Protestant upbringing, Babbage developed an obsession with the Devil. He asked his classmates to tell him every folk tales they knew about what forms the Devil appeared in.

Babbage didn't really believe in ghosts and spirits, but he decided to give them a fair chance and made a test of the tales his classmates had told him about the Devil. He went up to the school attic, cut himself and drew a circle on the floor and even recited the Lord's Prayer in reverse. It was obvious, though, that the Devil had no intention of making a pact with Charles Babbage -- none of his forms appeared, and Babbage was satisfied that all spirits and demons were figments of the imagination.

As he reached a healthy maturity, he went to a series of new schools, finally ending up at Forty Hill, where he was notorious for mischief combined with an odd desire to study. He was never a perfect scholar -- he carved his name in his desks, violated his curfew, and insulted the minister's sermons. But somehow he found time to wake up with a friend at three in the morning and study in the library until five thirty when they were scheduled to begin their regular day. Eventually his roommate, Frederick Marryat, a future novelist, managed to join the morning study group and brought bunches of friends along. Soon it degraded from studying to a wild party which was eventually broken up by the headmaster. Many years later, when he was a prosperous author and Babbage a famous mathematician, Marryat loved to tell people that he and Babbage had been known at Forty Hill as the two students who would never amount to anything.

Babbage's first invention came about one summer when he was at his father's country home. Swimming in the river, he realized that it would be easy to walk on water if he strapped huge books to his feet in such a way that when he lifted his foot up the book would close and when he set it down, the book would open, pushing or keeping him on top of the water's surface. The principle of the invention was correct, but the crude mechanics of it caused him to tilt heavily to one side and eventually fall into the water.

Shortly thereafter, Babbage's father acquired a tutor from Oxford to help finish his education to the point where he could be admitted to a college such as Cambridge. Babbage worked on grammar and reading the classics, but his passion was for mathematics. In his spare time he read such books as The Young Mathematician's Guide, Analytical Institutions (Madam Agnesi), many books of fluxions and Joseph Lagrange's Theorie des Fonctions, which described the work of another mathematician, Leibnitz, who used a "d" to represent what Newton's calculus used dots for. Babbage was impressed by the "d's" because they made reading the formulae much easier. The dots were small and could get blurred into the other symbols printed on the page, and were more easily forgotten by printers.

When he finally got to Cambridge at age nineteen, Babbage was frustrated by his teachers because they never answered his questions. He would listen to their lectures and then come up with new ideas based on what they had said. When he asked them about his ideas, they told him that he could rest assured he would not be tested on it. Even when he insisted that he wanted to know, the teachers refused to answer. Babbage soon concluded that none of the tutors or teachers at Cambridge knew as much about calculus as he did. His assumption was correct: the entire community of English mathematicians was very closed to change or new ideas coming from any corner, and calculus was rapidly changing.

Babbage's first service to the world as a mathematician was to throw some salt in the face of Cambridge. A controversy was going on at Cambridge about publishing an edition of the King James Bible with footnotes in it pointing out places where the translation was incorrect. The debate centered around challenging the letter of the Bible used by the Church of England. Babbage didn't care about the King James Bible, but he saw it as an excellent opportunity to parody the Cambridge mathematics department.

He wrote a flier about a fictional militant group of mathematicians who planned to translate new works about calculus that had not been written in English. The group would primarily focus on forcing the Cambridge mathematical community to accept Leibnitz's d's in the place of Newton's dots. Babbage showed the flier to a fellow student who showed it to a mathematician of some acclaim. The mathematician took it around to his friends and colleagues, and eventually one of them wondered why what started as a joke shouldn't become a reality.

Babbage and some other students formed the Analytical Society. The society met daily and wrote enough papers that they published a volume of transactions, mostly written by Babbage and John Herschel. Babbage remembered his original flier and entitled the transactions, The Principles of Pure d-ism in opposition to the Dot-age of the University. For obvious reasons, the Analytical Society was detested by the Cambridge mathematics department. Though they were a group of jokers, John Herschel, Charles Babbage and George Peacock also had a serious goal which Babbage summed up as: "Let us leave the world a wiser one than we found."

Babbage was also part of some sillier societies, including the Ghost Club, which investigated claims of the supernatural and, by far the most outlandish, the Extractors Club who made sure that every member of their group thrown in the madhouse was gotten out, legally, or illegally.

Meanwhile the Analytical Society busied itself by checking celestial tables used by sailors and astronomers for navigational and locational purposes respectively. Babbage noticed that the number of simple mathematical mistakes and printers' errors in the tables could have lost many lives at sea, and many opportunities to see celestial bodies for astronomers. Frustrated with the tables one evening while making corrections to them, Babbage got the idea that a machine could produce them, eliminating the simple human errors he found so frequently. This began his life's work on building adding machines.

Babbage started collecting calculating machines a few years later. He was searching for one that would not have or cause the problems he had seen in tables of numbers. It needed to be the sort of thing you could plug the numbers into, tell it the operation, and have it spit out the correct answer, whether or not the user understood the operation. It also needed to be "self acting" in that once an initial switch or lever was pulled it did all the work by itself. Aside from these criteria, he thought that a machine that printed out its answers would eliminate another place where human error was possible. He found no machine that met his standards, so he designed one.

Babbage's first calculating machine was the Difference Engine, which created tables of values by finding the common difference between terms in the sequence. The Difference Engine could print out a table of values for a number of terms in the sequence only limited by the number of digits the machine had available to work with. The idea was that astronomical tables could be printed out using such a machine, as well as simple lists of prices for a butcher's shop that charged by the pound.

The Difference Engine was wonderful for creating accurate tables of star positions at certain dates, for use by astronomers and sailors. The prototype of the machine was more accurate than human calculation, because it did not make stupid errors or miscopy its figures. The real model of the engine was never completed, much to the disappointment of the British government.

The Difference Engine was never completed because Babbage could never stick with a single blueprint for it. He had a habit of constantly thinking of ways to slightly improve it that involved new parts, ripping old parts out, and most notably, a great deal of money. Thousands of pounds of government funding were used rebuilding the same parts over and over as Babbage refined them. Never actually completed or used, the Difference Engine's main contribution to the world ended up being the ideas it inspired in Babbage's mind, which eventually lead to his next engine, and computer programming.

Babbage's real genius only manifested in his second attempt at creating an adding machine, the Analytical Engine. In three ways, the Analytical Engine led to modern computers. For this engine, Babbage borrowed a concept from the weaving industry -- punch cards. A Jacquard loom uses cards with patterns punched into them to tell the machinery what to weave. Babbage realized that mathematical functions could be placed on similar cards so that all a mathematician had to do was create the right card, and anybody could put it into the machine and set it to go.

Babbage devised two separate parts for the Analytical Engine, which were like a factory and a retailer. You told the retailer part of his device what you wanted to get in the end. Typing a simple command into a computer, such as "dir" in DOS is exactly this. You are telling the computer that you want a listing of everything in the specified directory. The computer then translates this into something its parts can understand; hence the retailer turns around and talks to the factory workers in a technical factory language. They complete the process, and give it back to the retailer, who must again translate it from their language to yours.

Before Babbage's intuition, mathematicians building adding machines had asked themselves the obvious question, "If we want this result, how can we get this result?" Babbage's roundabout approach to that question was the first part of the dream of computer programming. Without his concept of a translator, the modern computer program could not exist.

Late in the development of the Difference Engine, Babbage had realized that by connecting a few small gears, the engine could take the answer it had just found and run it through another set of manipulations. Babbage had discovered a sort of early virtual memory, and he built it into his plans for the Analytical Engine.

Unfortunately, the Analytical Engine was not heralded by British society as the most wonderful invention of the 19th century. It received almost no attention. After failing to complete the Difference Engine, Babbage fell out of favor with his mathematical peers. It wasn't until much later that his ideas were rediscovered, and combined with the findings of others (electric calculating machines) to create something very closely resembling a modern computer. But looking at Babbage's punch cards, they very closely resemble a modern program in Basic.

All of Babbage's work went toward making the daunting simple. His adding machines were meant to carry out tedious work perfectly, sparing human effort and mistakes. Babbage was devoted to making the world an easier one, to opening the doors of understanding and applications of mathematics. Eventually, his ideas went to this end, helping calculators and computers -- which are considered by many the finest tool of the modern era -- get their start.

He died lonely and cynical, but his ideas have met a bright future, bouncing from one field of study to another, from one corner of the world to the next.