William Oughtred - History of the Slide Rule Inventors Expert By Mary Bellis Before we had calculators we had slide rules. The circular (1632) and rectangular (1620) slide rules were invented by Episcopalian minister and mathematician William Oughtred. History of the Slide Rule A calculating tool, the invention of the slide rule was made possible by John Napier's invention of logarithms, and Edmund Gunter's invention of logarithmic scales, which slide rules are based upon. Logarithms According to The Museum of HP Calculators: Logarithms made it possible to perform multiplications and divisions by addition and subtraction. Mathematicians had to look up two logs, add them together and then look for the number whose log was the sum. Edmund Gunter reduced the labor by drawing a number line in which the positions of numbers were proportional to their logs. William Oughtred simplified things further with the slide rule by taking the two Gunter's lines and sliding them relative to each other thus eliminating the dividers. William Oughtred William Oughtred made the first slide rule by inscribing logarithms on wood or ivory. continue reading below our video Should I Buy my House or Continue to Rent?

Before the invention of the pocket or handheld calculator , the slide rule was a popular tool for calculations. The use of slide rules continued until about 1974, after which electronic calculators became more popular. Later Slide Rules Several inventors improved upon William Oughtred's slide rule. 1677 - Henry Coggeshall invented a 2 foot folding slide rule for lumber measure, called the Coggeshall slide rule. 1815 - Peter Mark Roget invented the log log slide rule, which included a scale displaying the logarithm of the logarithm. 1859 - French artillery lieutenant Amédée Mannheim invented an improved slide rule. 1891 - Edwin Thacher introduced a cylindrical slide rule in the United States. The duplex rule was invented by William Cox in 1891. Oughtred Society Slide Rule History. Slide Rule History Prologue In the 16th Century, engineering design as we know it today, with its emphasis on precise measurements and finely calculated tolerances, is unthinkable. And yet, every scientist, mathematician and alchemist feels that there are basic fundamental mathematical relationships that underpin the natural world.

The pre-eminent figures in science both contribute to the creation of the slide rule and make use of it in their work, including Galileo, Napier, Gunter, Oughtred, Newton, Gauss, Watt, Priestley, Fulton, Fuller, Einstein, Fermi, and Von Braun. A quick look at the first five of these men covers the creation and initial evolution of the slide rule. Just Before the Slide Rule Galileo Galilei popularizes the sector at the very end of the 16th Century. The sector is a graduated ruler that uses trigonometric formulae and a caliper to calculate squares, cubes, reciprocals and tangents of numbers. Galileo's design of the sector as a mathematical tool can be seen as the moment when calculation aids cease to be based upon counting and instead exploit the deeper relationships among numbers. His invention is still in use as a navigation aid in the 20th century … 300 years later. John Napier dramatically advances the understanding of number relationships in 1614 with his invention of logarithms. Since logarithms are the foundation on which the slide rule is built, its history rightly begins with him.

His early concept of simplifying mathematical calculations through logarithms makes possible the slide rule as we know it today. Chronology of the Slide Rule Napier himself contributes Napier's Bones in 1617, calculating sticks based on the gelosia, or lattice, multiplication method. In 1620 Edmund Gunter of London makes a straight logarithmic scale and performs multiplication and division on it with the use of a set of dividers, or calipers. In about 1622 William Oughtred, an Anglican minister … today recognized as the inventor of the slide rule … places two such scales side by side and slides them to read the distance relationships, thus multiplying and dividing directly. He also develops a circular slide rule. In 1675 Sir Isaac Newton solves cubic equations using three parallel logarithmic scales and makes the first suggestion toward the use of the cursor. In 1677, two years after Newton invents the cursor, Henry Coggeshall perfects the timber and carpenter's rule. Newton's cursor fails to catch on at the time. The Coggeshall rule remains in common use 200 years later.

His design and its standardization move the slide rule from a tool of mathematical inquiry to specialized applications. Beginning in 1683, Thomas Everard popularizes the gauging rule, used to determine the content of ale, wine and spirits barrels and to calculate the excise tax thereon. This design, first created by William Oughtred in 1633, sees widespread use well into the 19th century. In 1722 John Warner, a London instrument dealer, uses square and cube scales. By 1790 James Boulton and James Watt are modifying slide rules to improve their accuracy and usefulness. By 1799 their Soho slide rule helps to usher in the Industrial Revolution. It facilitates the design and manufacture of their seminal machine, the steam engine. In 1815 Peter Roget, an English physician (and the author of Roget's Thesaurus), invents a log log scale, which he uses to calculate roots and powers to any number or fraction thereof. It is regarded at the time as a mathematical curiosity.

Fifty years later, advances in electrical engineering, thermodynamics, dynamics and statics, and industrial chemistry make these scales so necessary they are rediscovered. In the next fifty years they increase from three, to six, to eight scales on the slide rule, as engineering extends its grip on modern computation. In 1851 a French artillery officer named Amedee Mannheim standardizes a set of four scales for the most common calculation problems. The four scales include two double length, named A & B, for squares and square roots … and two single length, C & D, for multiplication and division. This scale set becomes the basis of slide rule design for the next 100 years and bears his name today. His design and use of a cursor hastens the eventual widespread acceptance of this feature. Early in the 19th century the first slide rules come into use in the United States. Ex- president Thomas Jefferson has one, and Joseph Priestley recognizes their advantages in his chemistry work, which includes the discovery of oxygen. By 1870, Germany produces two giants of the slide rule world, Dennert and Pape (makers of Aristo), and Faber (later Faber-Castell).

The Dennert and Pape contributions of "engine divided" (engraved) scales and the stable deposit of celluloid on wood are revolutionary. The slide rule's importance to the Industrial Revolution, and the impact of the Industrial Revolution upon the slide rule, are demonstrated by the proliferation of designs. From 1625 to 1800, the first 175 years after its invention, a total of 40 slide rule types, including circular and spiral designs, are recorded. The next 100 years, from 1800 to 1899, sees the creation of 250 slide rule types and manufacturers. Over 90 designs are recorded in the first 10 years of the 20th Century. Cylindrical calculators with extra long logarithmic scales are invented by George Fuller of Ireland in 1878 and Edwin Thacher of New York in 1881. Production of Thacher's calculator is soon taken over by a Hoboken, New Jersey instruments company, Keuffel and Esser, which had previously imported slide rules for sale.

A revolutionary linear slide rule construction with scales on both front and back and with a cursor referring to all scales simultaneously is patented in 1891 by William Cox … an invention he calls the "duplex slide rule". It is sold by K&E. Folded scales CF, DF and CIF are put on slide rules about 1900 to reduce the amount of movement and resetting of the slide. Log log scales in three sections appear about 1901, enabling very accurate calculation of powers and roots to any number or fraction. The Slide Rule's Last Century … the 20th Our last century could not have been built without the slide rule, yet its direct evidence is almost totally missing to the uninformed eye. In the United States, this indispensability is seized upon most successfully by Keuffel and Esser. This firm moves from importing rules in the 1870s, to building a complex calculating instrument (the Thacher Calculator) in the 1880s, to manufacturing their own slide rules in the 1890s.

Their contributions are legion, including the CI scale, their fanatical devotion to precision, their use of colored scales and slanting italics to aid in reading direction. A different path to market dominance is adopted in Japan by Jiro Hemmi. Hemmi systematically experiments with both natural base materials and celluloid, settling upon bamboo as the core, and combining this with very modern manufacturing (including celluloid surface lamination), resulting in both high quality and quantity. In the 1960's Hemmi is producing one million slide rules annually. Epilogue The philosophy of engineering moves on. And the triumphs of 20th Century design become limitations for the slide rule. Einstein favors a Nestler slide rule in his work. The approaches to the Golden Gate Bridge and the thrust profile of the Redstone Rocket are designed with simple Rietz based slide rules … E. H. Lowry's Dietzgen Phillips 1725 and Wernher Von Braun's Nestler 23 respectively. Pickett slide rules provide emergency computational power aboard Apollo missions with their N600-ES model.

The Pickett N3 and N4 take their places along with the K&E Decilon and the Post Versalog in designing the F16 fighter airplane. But structural design and first principles in physics both seek answers to how structures will react to changing loads and forces. Wind speeds, tidal friction and interstellar collision all require dynamic computational models, rather than the answer to a static structural problem. Large, slow, obese computing engines designed for these questions give birth to the sleek four-function calculator. K&E's travails with its Analon slide rule model are an excellent example of the change in engineering demands that surpassed the slide rule. The four function electronic calculator is a symptom as much as a cause of this change. Slide rule researchers have estimated that possibly 40 million slide rules were produced in the world in the 20th century alone. Among these are many types of specialty slide rules developed and made for specific applications such as chemistry, surveying, electricity and electronics, artillery ranging, hydraulics, steam and internal combustion engines, concrete and steel structures, radio and other special fields. The slide rule has a long and distinguished ancestry … from William Oughtred in 1622 to the Apollo missions to the moon ...

a span of three and a half centuries … it was used to perform design calculations for virtually all the major structures built on this earth during that long period of our history … an amazing legacy for something so mechanically simple. History of Computers Ancient Times Early Man relied on counting on his fingers and toes (which by the way, is the basis for our base 10 numbering system). He also used sticks and stones as markers. Later notched sticks and knotted cords were used for counting. Finally came symbols written on hides, parchment, and later paper. Man invents the concept of number, then invents devices to help keep up with the numbers of his possessions. Roman Empire The ancient Romans developed an Abacus, the first "machine" for calculating. While it predates the Chinese abacus we do not know if it was the ancestor of that Abacus. Counters in the lower groove are 1 x 10n, those in the upper groove are 5 x 10n Industrial Age - 1600 John Napier, a Scottish nobleman and politician devoted much of his leisure time to the study of mathematics. He was especially interested in devising ways to aid computations. His greatest contribution was the invention of logarithms.

He inscribed logarithmic measurements on a set of 10 wooden rods and thus was able to do multiplication and division by matching up numbers on the rods. These became known as Napier�s Bones. 1621 - The Sliderule Napier invented logarithms, Edmund Gunter invented the logarithmic scales (lines etched on metal or wood), but it was William Oughtred, in England who invented the sliderule. Using the concept of Napier�s bones, he inscribed logarithms on strips of wood and invented the calculating "machine" which was used up until the mid-1970s when the first hand-held calculators and microcomputers appeared. 1642 - Blaise Pascal(1623-1662) Blaise Pascal, a French mathematical genius, at the age of 19 invented a machine, which he called the Pascaline that could do addition and subtraction to help his father, who was also a mathematician. Pascal�s machine consisted of a series of gears with 10 teeth each, representing the numbers 0 to 9. As each gear made one turn it would trip the next gear up to make 1/10 of a revolution.

This principle remained the foundation of all mechanical adding machines for centuries after his death. The Pascal programming language was named in his honor. 1673 - Gottfried Wilhelm von Leibniz (1646-1716) Gottfried Wilhelm von Leibniz invented differential and integral calculus independently of Sir Isaac Newton, who is usually given sole credit. He invented a calculating machine known as Leibniz�s Wheel or the Step Reckoner. It could add and subtract, like Pascal�s machine, but it could also multiply and divide. It did this by repeated additions or subtractions, the way mechanical adding machines of the mid to late 20th century did. Leibniz also invented something essential to modern computers � binary arithmetic. 1725 - The Bouchon Loom Basile Bouchon, the son of an organ maker, worked in the textile industry. At this time fabrics with very intricate patterns woven into them were very much in vogue. To weave a complex pattern, however involved somewhat complicated manipulations of the threads in a loom which frequently became tangled, broken, or out of place.

Bouchon observed the paper rolls with punched holes that his father made to program his player organs and adapted the idea as a way of "programming" a loom. The paper passed over a section of the loom and where the holes appeared certain threads were lifted. As a result, the pattern could be woven repeatedly. This was the first punched paper, stored program. Unfortunately the paper tore and was hard to advance. So, Bouchon�s loom never really caught on and eventually ended up in the back room collecting dust. 1728 - Fal�on Loom In 1728 Jean-Batist Fal�on, substituted a deck of punched cardboard cards for the paper roll of Bouchon�s loom. This was much more durable, but the deck of cards tended to get shuffled and it was tedious to continuously switch cards. So, Fal�on�s loom ended up collecting dust next to Bouchon�s loom. 1745 - Joseph Marie Jacquard (1752-1834) It took inventor Joseph M.

Jacquard to bring together Bouchon�s idea of a continuous punched roll, and Falcon�s ides of durable punched cards to produce a really workable programmable loom. Weaving operations were controlled by punched cards tied together to form a long loop. And, you could add as many cards as you wanted. Each time a thread was woven in, the roll was clicked forward by one card. The results revolutionized the weaving industry and made a lot of money for Jacquard. This idea of punched data storage was later adapted for computer data input. 1822 � Charles Babbage (1791-1871) and Ada Augusta, The Countess of Lovelace Charles Babbage is known as the Father of the modern computer (even though none of his computers worked or were even constructed in their entirety). He first designed plans to build, what he called the Automatic Difference Engine. It was designed to help in the construction of mathematical tables for navigation. Unfortunately, engineering limitations of his time made it impossible for the computer to be built. His next project was much more ambitious.

While a professor of mathematics at Cambridge University (where Stephen Hawkin is now), a position he never actually occupied, he proposed the construction of a machine he called the Analytic Engine. It was to have a punched card input, a memory unit (called the store), an arithmetic unit (called the mill), automatic printout, sequential program control, and 20-place decimal accuracy. He had actually worked out a plan for a computer 100 years ahead of its time. Unfortunately it was never completed. It had to wait for manufacturing technology to catch up to his ideas. During a nine-month period in 1842-1843, Ada Lovelace translated Italian mathematician Luigi Menabrea's memoir on Charles Babbage's Analytic Engine. With her translation she appended a set of notes which specified in complete detail a method for calculating Bernoulli numbers with the Engine. Historians now recognize this as the world's first computer program and honor her as the first programmer. Too bad she has such an ill-received programming language named after her. 1880s � Herman Hollerith (1860-1929) The computer trail next takes us to, of all places, the U.S.

Bureau of Census. In 1880 taking the U.S. census proved to be a monumental task. By the time it was completed it was almost time to start over for the 1890 census. To try to overcome this problem the Census Bureau hired Dr. Herman Hollerith. In 1887, using Jacquard�s idea of the punched card data storage, Hollerith developed a punched card tabulating system, which allowed the census takers to record all the information needed on punched cards which were then placed in a special tabulating machine with a series of counters. When a lever was pulled a number of pins came down on the card. Where there was a hole the pin went through the card and made contact with a tiny pool of mercury below and tripped one of the counters by one. With Hollerith�s machine the 1890 census tabulation was completed in 1/8 the time. And they checked the count twice. After the census Hollerith turned to using his tabulating machines for business and in 1896 organized the Tabulating Machine Company which later merged with other companies to become IBM.

His contribution to the computer then is the use of punched card data storage. BTW: The punched cards in computers were made the same size as those of Hollerith�s machine. And, Hollerith chose the size he did because that was the same size as the one dollar bill at that time and therefore he could find plenty of boxes just the right size to hold the cards. 1939-1942 Dr. John Vincent Atanasoff(1903-1995) and Clifford Berry (1918-1963) Dr. John Vincent Atanasoff and his graduate assistant, Clifford Barry, built the first truly electronic computer, called the Atanasoff-Berry Computer or ABC. Atanasoff said the idea came to him as he was sitting in a small roadside tavern in Illinois. This computer used a circuit with 45 vacuum tubes to perform the calculations, and capacitors for storage. This was also the first computer to use binary math. 1943 � Colossus I The first really successful electronic computer was built in Bletchley Park, England. It was capable of performing only one function, that of code breaking during World War II.

It could not be re-programmed. 1944 � Mark I - Howard Aiken (1900-1973) and Grace Hopper (1906-1992) In 1944 Dr. Howard Aiken of Harvard finished the construction of the Automatic Sequence Controlled Calculator, popularly known as the Mark I. It contained over 3000 mechanical relays and was the first electro-mechanical computer capable of making logical decisions, like if x==3 then do this not like If its raining outside I need to carry an umbrella. It could perform an addition in 3/10 of a second. Compare that with something on the order of a couple of nano-seconds (billionths of a second) today. The important contribution of this machine was that it was programmed by means of a punched paper tape, and the instructions could be altered. In many ways, the Mark I was the realization of Babbage�s dream. One of the primary programmers for the Mark I was Grace Hopper. One day the Mark I was malfunctioning and not reading its paper tape input correctly.

Ms Hopper checked out the reader and found a dead moth in the mechanism with its wings blocking the reading of the holes in the paper tape. She removed the moth, taped it into her log book, and recorded... Relay #70 Panel F (moth) in relay. First actual case of bug being found. She had debugged the program, and while the word bug had been used to describe defects since at least 1889, she is credited with coining the word debugging to describe the work of eliminating program errors. It was Howard Aiken, in 1947, who made the rather short-sighted comment to the effect that the computer is a wonderful machine, but I can see that six such machines would be enough to satisfy all the computing needs of the entire United States. 1946 � ENIAC - J. Prosper Eckert (1919-1995) and John W. Mauchly (1907-1980) The first all electronic computer was the Electrical Numerical Integrator and Calculator, known as ENIAC. It was designed by J. Prosper Eckert and John W.

Mauchly of the Moore School of Engineering at the University of Pennsylvania. ENIAC was the first multipurpose electronic computer, though very difficult to re-program. It was primarily used to computer aircraft courses, shell trajectories, and to break codes during World War II. ENIAC occupied a 20 x 40 foot room and used 18,000 vacuum tubes. ENIAC also could never be turned off. If it was it blew too many tubes when turned back on. It had a very limited storage capacity and it was programmed by jumper wires plugged into a large board. 1948 � The Transister In 1948 an event occurred that was to forever change the course of computers and electronics. Working at Bell Labs three scientists, John Bordeen (1908-1991) (left), Waltar Brattain (1902-1987) (right), and William Shockly (1910-1989) (seated) invented the transistor. The change over from vacuum tube circuits to transistor circuits occurred between 1956 and 1959.

This brought in the second generation of computers, those based on transisters. The first generation was mechanical and vacuum tube computers. 1951 � UNIVAC The first practical electronic computer was built by Eckert and Mauchly (of ENIAC fame) and was known as UNIVAC (UNIVersal Automatic Computer). The first UNIVAC was used by the Bureau of Census. The unique feature of the UNIVAC was that it was not a one-of-a-kind computer. It was mass produced. 1954 � IBM 650 In 1954 the first electronic computer for business was installed at General Electric Appliance Park in Louisville, Kentucky. This year also saw the beginning of operation of the IBM 650 in Boston. This comparatively inexpensive computer gave IBM the lead in the computer market. Over 1000 650s were sold. 1957-59 � IBM 704 From 1957-1959 the IBM 704 computer appeared, for which the Fortran language was developed. At this time the state of the art in computers allowed 1 component per chip, that is individual transistors.

1958 - 1962 � Programming languages From 1958-1962 many programming languages were developed. (Beginners All-purpose Symbolic Instruction Code) 1964 � IBM System/360 In 1964 the beginning of the third-generation computers came with the introduction of the IBM System/360. Thanks to the new hybrid circuits (that gross looking orange thing in the circuit board on the right), the state of the art in computer technology allowed for 10 components per chip. 1965 - PDP-8 In 1965 the first integrated circuit computer, the PDP-8 from Digital Equipment Corporation appeared. (PDP stands for Programmable Data Processor) After this the real revolution in computer cost and size began. 1970 - Integrated Circuits By the early 70s the state of the art in computer technology allowed for 1000 components per chip. To get an idea of just how much the size of electronic components had shrunk by this time look at the image on the right. The woman is peering through a microscope at a 16K RAM memory integrated circuit.

The stand she has her microscopy sitting on is a 16K vacuum tube memory curcuit from about 20 years previous. 1971 The Intel corporation produced the first microprocessor chip which was a 4-bit chip. Today�s chips are 64-bit. At approximately 1/16 x 1/8 inches in size, this chip contained 250 transistors and had all the computing power of ENIAC. It matched IBM computers of the early 60s that had a CPU the size of an office desk. 1975 � Altair 8800 The January 1975 issue of Popular Electronics carried an article, the first, to describe the Altair 8800, the first low-cost microprocessor computer which had just became commercially available. Late 1970s to early 1980s � The Microcomputer Explosion During this period many companies appeared and disappeared, manufacturing a variety of microcomputers (they were called micro to distinguish them from the mainframes which some people referred to as real computers). There was Radio Shack�s TRS-80, the Commodore 64, the Atari, but...

1977 - The Apple II The most successful of the early microcomputers was the Apple II, designed and built by Steve Wozniak. With fellow computer whiz and business savvy friend, Steve Jobs, they started Apple Computer in 1977 in Woz�s garage. Less than three years later the company earned over $100 million. Not bad for a couple of college dropout computer geeks. Click here to see an interesting article from the March 2016 issue of Smithsonian Magazine about Woz and the Apple I. 1981 In 1981, IBM produced their first microcomputer. Then the clones started to appear. This microcomputer explosion fulfilled its slogan computers by the millions for the millions. Compared to ENIAC, microcomputers of the early 80s: Were 20 times faster (Apple II ran at the speed of � Megahertz). Had a memory capacity as much as 16 times larger (Apple had 64 K). Were thousands of times more reliable. Consumed the power of a light bulb instead of a locomotive. Were 1/30,000 the size.

Cost 1/10,000 as much in comparable dollars (An Apple II with full 64 K of RAM cost $1200 in 1979. That�s the equivalent of about $8000 to $10000 in today's dollars) 1984-1989 In 1984 the Macintosh was introduced. This was the first mass-produced, commercially-available computer with a Graphical User Interface. In 1989 Windows 1.0 was introduced for the PC. It was sort of Mac-like but greatly inferior. Macintosh owners were know to refer to it sarcastically as AGAM-84 Almost as Good As Macintosh 84.

1990s Compared to ENIAC, microcomputers of the 90s: Were 36,000 times faster (450 Megahertz was the average speed) Had a memory capacity 1000 to 5000 times larger (average was between 4 and 20 Megabytes) Were 1/30,000 the size Cost 1/30,000 as much in comparable dollars (A PC still cost around $1500 the equivalent of about $2500 in 2008 dollars) Early 2000s Compared to ENIAC, microcomputers of the early 2000s: Are 180,000 times faster (2.5+ Gigahertz is the average speed) Have a memory capacity 25,000 times larger (average 1+ Gigabytes of RAM) Are 1/30,000 the size Cost 1/60,000 as much in comparable dollars (A PC can cost from $700 to $1500) Data Storage Data storage has also grown in capacity and shr

unk in size as dramatically as have computers.

Today a single data DVD will hold around 4.8 gigabytes. It would take 90,000,000 punch cards to hold the same amount of data. And, there is talk of a new high density video disk (HVD) that will be able to hold fifty times that much data. That's more than 240 gigabytes.

Just how much data is that 8 bits = 1 byte 1024 K = 1 Megabyte = 1,048,576 bytes 1024 Mb = 1 Gigabyte = 10,73,741,824 bytes 1024 Gb = 1 Terabyte = 1,099,511,627,776 bytes 1024 Tb = 1 Petabyte = 1,125,899,906,842,624 bytes 1024 Pb = 1 Exabyte = 1,152,921,504,606,846,976 bytes 1024 Eb = 1 Zettabyte = 1,180,591,620,717,411,303,424 bytes 1024 Zb = 1 Yottabyte = 1,208,925,819,614,629,174,70

6,176 bytes By comparison 1K is approximately the memory needed to store one single spaced typed page.

Slide Rule,Slide Rule inventors | edubilla.com : Computing About Invention The slide rule, also known colloquially in the United States as a slipstick,is a mechanical analog computer.The slide rule is used primarily for multiplication and division, and also for functions such as roots, logarithms and trigonometry, but is not normally used for addition or subtraction. Though similar in name and appearance to a standard ruler, the slide rule is not ordinarily used for measuring length or drawing straight lines. The slide rule was invented around 1620–1630, shortly after John Napier's publication of the concept of the logarithm. Edmund Gunter of Oxford developed a calculating device with a single logarithmic scale, which, with additional measuring tools, could be used to multiply and divide. The first description of this scale was published in Paris in 1624 by Edmund Wingate (c.1593–1656), an English mathematician, in a book entitled L'usage de la reigle de proportion en l'arithmetique & geometrie. The book contains a double scale on one side of which is a logarithmic scale and on the other a tabular scale.

In 1630, William Oughtred of Cambridge invented a circular slide rule, and in 1632 he combined two Gunter rules, held together with the hands, to make a device that is recognizably the modern slide rule. Like his contemporary at Cambridge, Isaac Newton, Oughtred taught his ideas privately to his students, but delayed in publishing them, and like Newton, he became involved in a vitriolic controversy over priority, with his one-time student Richard Delamain and the prior claims of Wingate. Oughtred's ideas were only made public in publications of his student William Forster in 1632 and 1653. In 1677, Henry Coggeshall created a two-foot folding rule for timber measure, called the Coggeshall slide rule. His design and uses for the tool gave the slide rule purpose outside of mathematical inquiry. In 1722, Warner introduced the two- and three-decade scales, and in 1755 Everard included an inverted scale, a slide rule containing all of these scales is usually known as a ""polyphase"" rule.

In 1815, Peter Mark Roget invented the log log slide rule, which included a scale displaying the logarithm of the logarithm. This allowed the user to directly perform calculations involving roots and exponents. This was especially useful for fractional powers. In 1821, Nathaniel Bowditch, in the American Practical Navigator, described the use of a ""sliding rule"" that contained scales trigonometric functions on the fixed part and a line of log-sines and log-tans on the slider. This device was used to solve navigation problems. In 1845, Paul Cameron of Glasgow introduced the Nautical Slide-Rule. designed to answer questions of navigation including right ascension and declination of the sun and principal stars. The more modern form was created in 1859 by French artillery lieutenant Amédée Mannheim, ""who was fortunate in having his rule made by a firm of national reputation and in having it adopted by the French Artillery."" It was around that time, as engineering became a recognized professional activity, that slide rules came into wide use in Europe. They did not become common in the United States until 1881, when Edwin Thacher introduced a cylindrical rule there.

The duplex rule was invented by William Cox in 1891, and was produced by Keuffel and Esser Co. of New York. Astronomical work also required fine computations, and in 19th-century Germany a steel slide rule about 2 meters long was used at one observatory. It had a microscope attached, giving it accuracy to six decimal places. Throughout the 1950s and 1960s the slide rule was the symbol of the engineer's profession (in the same way that the stethoscope symbolizes the medical profession).German rocket scientist Wernher von Braun brought two 1930s vintage Nestler slide rules with him when he moved to the U.S. after World War 2 to work on the American space program. Throughout his life he never used any other pocket calculating devices; slide rules served him perfectly well for making quick estimates of rocket design parameters and other figures. Aluminium Pickett-brand slide rules were carried on Project Apollo space missions.

The Pickett model N600-ES that was taken to the moon on Apollo 13 in 1970 is owned by the National Air and Space Museum.The Pickett N600-ES that was owned by Buzz Aldrin and flew with him to the moon on Apollo 11 was sold at auction in 2007.Some engineering students and engineers carried ten-inch slide rules in belt holsters, and even into the mid-1970s this was a common sight on campuses. Students also might keep a ten- or twenty-inch rule for precision work at home or the office while carrying a five-inch pocket slide rule around with them. In 2004, education researchers David B. Sher and Dean C. Nataro conceived a new type of slide rule based on prosthaphaeresis, an algorithm for rapidly computing products that predates logarithms. There has been little practical interest in constructing one beyond the initial prototype, however. Computer History for 1600's William Gilbert coins the term electricity from the Greek word elecktra. 1600 The Microsoft Windows Epoch time is set to start January 1, 1601.

1605 Francis Bacon devices the Baconian Cipher, a cipher that used A's and B's to encode messages. 1613 The word " computer " was first recorded as being used in 1613 and was originally used to describe a person who performed calculations or computations. The definition of a computer remained the same until the end of the 19th century when it began referring to a machine that performed calculations. 1613 Claude Perrault is born September 25, 1613. 1614 John Napier illustrates and puts forward the idea of Logarithms. 1617 John Napier introduced a system called "Napiers Bones," made from horn, bone or ivory the device allowed the capability of multiplying by adding numbers and dividing by subtracting. 1617 Tito Burattini is born March 8, 1617. 1617 John Napier passes away April 4, 1617 (Age: 66-67) 1621 The circular slide rule is invented by William Oughtred. 1623 Blaise Pascal is born June 19, 1623.

1623 The first known workable mechanical calculating machine is invented by Germanys Wilhelm Schickard. The machine is based on the idea of Napier's Bones, mentioned earlier. 1625 Samuel Morland is born in 1625 1626 Francis Bacon passes away April 9, 1626 (Age: 65) 1626 Edmund Gunter passes away December 10, 1626 (Age: 45) 1630 Henry Briggs passes away January 26, 1630 (Age: 68) 1630 Johannes Kepler passes away November 15, 1630 (Age: 58) 1632 William Oughtred of Cambridge combines two Gunter rules to make a device that resembles today's slide rule. 1935 Robert Hooke is born July 28, 1635.

1635 Wilhelm Schickard passes away October 24, 1635 (Age: 43) 1642 Frances Blaise Pascal invents a machine, called the Pascaline , that can add, subtract, and carry between digits. 1642 Isaac Newton is born December 25, 1642. 1646 Gottfried Leibniz is born July 1, 1646. 1650 René Descartes passes away February 11, 1650 (Age: 53) 1662 Blaise Pascal passes away August 19, 1662 (Age: 39) 1671 Gottfried Leibniz introduces the Step Reckoner, a device that can multiply, divide, and evaluate square roots. 1679 Gottfried Leibniz demonstrates binary arithmetic, a discovery that shows every number can be represented by 0 and 1 only.

1681 Tito Livio Burattini passes away November 17, 1681 (Age: 64) 1688 Claude Perrault passes away in 1688 (Age: 75) 1695 John Napier, Mathematician - Biography and Profile By Mary Bellis Updated August 06, 2016. The hand without a thumb is at worst nothing but an animated spatula and at best a pair of forceps whose points don't meet properly - John Napier John Napier was a Scottish mathematician and inventor. Napier is famous for creating mathematical logarithms, creating the decimal point, and for inventing Napier's Bones, a calculating instrument. John Napier - Inventor While better known as a mathematician, John Napier was a busy inventor. He proposed several military inventions including: burning mirrors that set enemy ships on fire, special artillery that destroyed everything within a radius of four miles, bulletproof clothing, a crude version of a tank, and a submarine-like device. John Napier invented a hydraulic screw with a revolving axle that lowered water levels in coal pits.

Napier also worked on agricultural innovations to improve crops with manures and salt. John Napier - Mathematician As a Mathematician, the highlight of John Napier's life was the creation of logarithms and the decimal notation for fractions. continue reading below our video Should I Roll Over my 401K to an IRA? His other mathematical contributions included: a mnemonic for formulas used in solving spherical triangles, two formulas known as Napier's analogies used in solving spherical triangles, and the exponential expressions for trigonometric functions. In 1621, English mathematician and clergyman, William Oughtred used Napier's logarithms when he invented the slide rule. Oughtred invented the standard rectilinear slide rule and circular slide rule. John Napier - Napier's Bones Napier's bones were multiplication tables written on strips of wood or bones. The invention was used for multiplying, dividing, and taking square roots and cube roots. Resistance to Useful Inventions - Engineering and Technology History Wiki Request account Resistance to Useful Inventions The history of technology is filled with inventions which languished while their inventors attempted to interest investors and developers of their products. At the same time, investors put money into other projects.

Why do some inventions face resistance, and why do others seem to have their paths paved for them? The relative value of the idea seems to have little to do with this effect. As a case study, the calculator is a good example of a device which has taken the "slow track" through its very long history. Depending on whether you count the abacus (2300 BCE) , the slide rule (William Oughtred, 1621 C.E.), or Blaise Pascal's first mechanical calculator (1642 C.E.) as the beginning of calculator technology, the road to development and wide customer acceptance has been a long one. Pascal's calculator was expensive to build and maintain, and few-- if any-- were actually sold at the time. This "delayed adoption" by consumers certainly had nothing to do with the utility of the device. Indeed, many applications-- navigation, business, engineering, science, to name but a few-- were crying out for rapid and error-free calculation, even before the Enlightenment had accelerated the demand. Moreover, the appeal of a machine which could "think" should have made it fascinating to the public and generated interest in addition to the utility of the device.

One of the earliest commercially successful mechanical calculators was the Arithmometer, invented by a French insurance executive, Charles Xavier Thomas de Colmar, in 1820. Even so, it had a long road to anything approaching wide adoption; only after it won a prize at an exhibition forty-seven years later did sales of the machine blossom. Not until the 1920s and 1930s did calculators — their costs reduced and reliability increased by mass-production techniques — become truly widespread, three hundred years after Oughtred's and Pascal's devices. Significantly, abacuses and slide rules continued in use until the 1970s and the arrival of the very powerful and very inexpensive electronic pocket calculators. Given that all the mechanical components were in place by the end of the 19th century, and given the demand, why wasn't there an economic incentive to come up with design solutions much earlier? Certainly mechanical complexity or machining was not an obstacle-- intricate clocks and orreries had been understood and built for centuries prior to the mechanical calculator.

Artisans capable of constructing Raineri's elegant clock in Venice with its procession of the magi led by an angel with a trumpet which actually sounded (1493), the Strassbourg clock with its angels, hourglasses, and roosters (1354), or Prague's astronomical clock (date uncertain), would not have had any trouble knocking together calculating machines. Indeed, Blaise Pascal owned a pocket watch (he is said to have pioneered the wristwatch by attaching it to his wrist with string) which was already far more complex a device than his calculator. So, why such slow adoption? Why did the calculator not follow the same path of increasingly widespread manufacture and price reduction that the clock did, such that almost everyone would own one by the beginning of the 19th century? Partly, it was the size and expense of the commercial product. Napier's bones or Oughtred's slide rule could do for a fraction of the cost what a mechanical calculator could do for three centuries. Perhaps most tellingly, it was the relative size of brain work versus muscle work in the economies of the world prior to the end of the Industrial Revolution.

At a time when most work was physical, there weren't that many people doing calculations as a proportion of the population. Everyone might have needed a clock in their lives, but not everyone needed to do calculations. Another personal device, the transistor radio, by contrast, was an invention that was eagerly and rapidly pushed forward. The time elapsed from glimmer of idea (1951) to mass market release (1954) was a blistering three years. The first designs were conceived, and a working prototype built, in the period between a Friday afternoon and the following Tuesday afternoon. Consumer acceptance of the transistor radio was just as rapid; demand quickly outpaced supply. The irony is that the transistor radio was not a goal in itself. Pat Haggerty , at Texas Instruments, saw it as a way to learn about transistor manufacturing, and to develop a high-volume application for the newly-invented device. In 1955, the first full year on the market, TI made half as many transistors for that radio alone as the entire industry had made previously. Another particularly pricky invention was the Pacemaker.

It was invented by a Sydney doctor in 1926, who wished to remain anonymous, from the Crown Street Women’s Hospital in Sydney. He resuscitates a new-born baby with an electrical device later called an electric 'pacemaker'. {Variants on this invention are also claimed by Hyman in mid 1930’s, Hopp in 1949 and Zoll in 1952}. One of the fundamental reasons this invention fell foul of society was the strong religious and conservative values that permeated society in the 1920's and 30's. It was not socially or religously acceptable to intefere with life and prolong it with a machine. Being part of a larger agenda may be the most important factor of all in the development and adoption of an invention. If you want a device to succeed, make it part of a larger whole.

Culture and society | Computers and information processing | Computer classes | Calculators | Communications | Communication equipment | Radio communication equipment | Components, circuits, devices & systems | Solid state circuits | Transistors | Measurement | Time measurement | News William Oughtred facts, information, pictures | Encyclopedia.com articles about William Oughtred COPYRIGHT 2004 The Gale Group Inc. William Oughtred Anglican clergyman William Oughtred (1574-1660) is considered one of the world's great mathematicians due to his writings on the subject and his invention of the logarithmic slide rule. Although William Oughtred was by profession an Anglican clergyman, he devoted many years of his life to expanding human understanding in the areas of algebra and calculus as well as to teaching mathematics to gifted students. Oughtred was the author of several books on mathematics and has also been credited by most historians with inventing both the linear and circular slide rules. His innovations extended to the use of many unique mathematical shorthand notations, including the notation "X" for multiplication and "::" for proportion. Raised in Academic Environment Oughtred was born in Eton, Buckinghamshire, England, on March 5, 1574.

His father, Benjamin Oughtred, was a scholar who taught writing at Eton School, and through Benjamin's connections the younger Oughtred was educated as a king's scholar at Eton. At age 15 he entered King's College of Cambridge University and became a fellow there in 1595. Oughtred went on to receive his bachelor's degree from King's College, Cambridge, in 1596, followed by a masters of arts degree four years later. Despite the fact that Oughtred's studies at Cambridge consisted predominately of philosophy and theology, as early as age 12 he had demonstrated an extraordinary interest and talent in all things mathematical. As a college student, he had built on the rudimentary mathematical study provided to him at Eton, studying late into the night after completing his required regular studies. By the time of his graduation from Cambridge, Oughtred had already completed his first work, titled Easy Method of Mathematical Dialling. In 1603 the 29-year-old Oughtred was ordained an Episcopal minister, a common and well-respected career option for an educated man.

Applying to the church soon afterward, he gained an appointment as vicar of Shalford in 1604. In 1610 Oughtred was promoted to a position as rector of Albury, near Guilford, Surrey, in which post he served at an annual salary of 100 pounds. During his first years at Albury Oughtred married and set about tending to his parish. Despite the fame he would eventually acquire as a well-known mathematician, he remained dedicated to his flock and held his position as rector of Albury for nearly half a century, until his death in 1660. Although never formally trained in mathematics, Oughtred clearly had a genius for the subject. Through his writings, he quickly gained renown as a mathematician and soon began to divide the time left to him after his church duties between personal study and the instruction of others. During the 1620s he began to take on as private pupils young men interested in the study of mathematics. These students—among whom were future mathematicians Richard Delamain and John Wallis as well as Christopher Wren, the future architect of St.

Paul's Cathedral—shared the home and hospitality of their teacher during their mathematical studies. Eager to impart his mathematical knowledge to these brilliant young minds, Oughtred refused payment, maintaining that he was adequately provided for by his salary as a clergyman. A small man with black hair and a quick, penetrating gaze, he became known for impatiently etching mathematical diagrams in the dust that settled on tables and floors. It was not unusual, in the Oughtred home, to find its owner dressed and awake in the middle of the night while hard at work solving a mathematical problem. On his bed he had permanently affixed an ink-horn, while on the nightstand nearby a candle and tinderbox lay in easy reach, ready for the many nights when a mathematical quandary would demand a solution before Oughtred would allow himself to sleep. In 1628 Oughtred became math tutor to Lord William Howard, son of the earl of Arundel. Desiring a suitable text to supplement his instruction of the young aristocrat, Oughtred wrote out, in summary form, all that was currently known about arithmetic and algebra.

Pleased by the mathematician's efforts on behalf of his son, the earl of Arundel became a patron of Oughtred's and encouraged the rector of Albury to publish his work. The 88-page Arithmeticae in numeris et speciebus instituto … quasi clavis mathematicae est —known more commonly as Clavis mathematicae —was first published in Latin in 1631. Despite its condensed format, the book quickly drew interest from Oughtred's fellow mathematicians. By the time the second edition of the work was released in 1658, its author's reputation had been cemented in the larger community of European scientists. In his Clavis mathematicae Oughtred describes the Hindu-Arabic system of mathematical notation, sets forth the theory of decimal fractions, and includes a detailed discussion of algebra. Throughout the work he incorporates a number of mathematical shorthand notations he had devised as a way to denote powers, relationships, ratios, and the like.

While much of Oughtred's mathematical shorthand was rejected by readers as being too complicated, two of his symbols—"X" for multiplication and "::" for proportion—have gone on to become part of universal mathematical shorthand, along with those of contemporary mathematician and scientist Thomas Harriot (circa 1530-1621). Although Oughtred utilized the notation π as one of his symbols, its use signified only the circumference of a circle, not the ratio of the circumference to the diameter as it has come to denote. Developed Logarithmic Slide Rule The logarithmic slide rule was designed in response to the demands of the scientific renaissance that overtook Europe during Oughtred's lifetime. The astronomical calculus that grew from the work of such men as German astronomer Johann Kepler (1571-1630) and which would appear throughout the work of English scientist Sir Isaac Newton (1624-1727) demanded a means by which the multiplication and division of both extremely small and extremely large numbers could be performed quickly. These scientific and technical calculations were performed with ease using logarithms, which raise or reduce one number to an abbreviated form through the use of exponents.

The invention of logarithms is usually credited to Scottish mathematician and inventor John Napier, baron of Merchiston (1550-1617), who described his invention in 1614 in Logarithmorum canonis descriptio, although Swiss watchmaker and mathematician Justus Byrgius (1552-1633) also compiled such a system of mathematical shorthand. Napier's invention was simplified by a colleague at the University of London, professor Henry Briggs (1561-1631), who suggested that the system be designed in base 10 rather than Napier's base "e." Logarithms paved the way for the expanded scientific revolution that followed, allowing that complex operations of products and quotients be completed using simpler additions and subtractions. Their use continued until the advent of the digital calculator and the electronic computer of the twentieth century. The use of logarithms immediately suggested an instrument that could speed calculations, and that instrument was the slide rule, an analogic calculator that through its mechanism allows for the processing of the variable data represented by logarithms.

In 1620 astronomer and mathematician Edmund Gunter (1581-1626) devised "Gunter's Line," a two-foot-long ruler marked with a logarithmic scale. For operations such as the multiplication or division of numbers to several places, lengths along the ruler that are equivalent to the logarithms of the relevant numbers are added and subtracted using a pair of calipers and the result converted back to numeric form through the use of the logarithmic table. Oughtred is believed to have designed the first linear slide rule after less than a year spent wrestling with Gunter's Line and its calipers. Using two rules placed parallel to one another and connected, the position of the numbers relative to each other could now be used to calculate the desired results. By discarding the calipers, Oughtred created the prototype of the modern slide rule. In its earliest manufactured form slide rules were made of wood, ivory, and even bamboo. They also were designed in several versions: Oughtred's linear and circular versions came first, followed by a cylindrical version, each version adapted for a particular academic discipline.

The slide rule quickly gained prominence as a calculating device in every field of science and technology, from astronomy to topography to chemistry to mechanical engineering. However, it was not until the end of the eighteenth century that its importance was made clear by inventor James Watt (1736-1819), who revalued it as a tool of the Industrial Revolution. Demand for slide rules became such that by 1850 they had supplanted the use of Galileo's compass of proportions, an instrument initially intended for military use. In 1850 French army officer Victor Mayer Amdée Mannheim (1831-1906) introduced a transparent slab movable cursor; other modifications and improvements continued to be introduced in the decades that followed, resulting in the slide rule of the twentieth century. Later Career Overshadowed by Controversy The positive reception of his Clavis mathematicae within the scientific community prompted Oughtred to write several other books on mathematics.

His 1632 work, titled Circles of Proportion and the Horizontal Instrument, described both a sundial and a circular form of slide rule that operated like Oughtred's linear slide rule: it was constructed using two concentric rings, one seated inside the other and both of which were inscribed with calibrated logarithmic scales. Ironically, this concentric slide rule, which Oughtred designed for use as a navigational instrument, had been described in a book titled Grammelogia; or, The Mathematical Ring published in 1630 by Oughtred's former student, Richard Delamain. Credit for the invention of the circular slide rule was claimed by both teacher and pupil, resulting in an enmity that lasted for the rest of Oughtred's life. Despite the likelihood that Oughtred and Delamain each individually devised the instrument, history has ultimately granted Oughtred credit for the circular slide rule. During the final decades of his life Oughtred published six more books, among them 1657's Trigonometria, which supplements its discussion of two-and three-dimensional triangles with symbolism and tables setting forth the values of trigonometric and logarithmic functions to seven places.

His 1651 work, The Solution of All Spherical Triangles, discusses the means by which the relative measurements of three-dimensional triangles can be determined; other books by Oughtred cover such subjects as the methods by which the position of the sun can be calculated and a discussion of the art of watchmaking. Oughtred lived during tumultuous times in England. A staunch supporter of the English crown, he was shocked by the execution of the unpopular King Charles I in January of 1649. Like many who supported the cause of Charles I's son, the Prince of Wales (later Charles II), Oughtred was viewed with suspicion by the Presbyterian-influenced government that desired to take the place of the monarchy through the will of its leader, Oliver Cromwell. During the English Civil War (1642-1646) Oughtred was sequestered and scheduled for trial before Cromwell's puritanical commissioners. Due to the quick action of the astrologer Lilly and the insistence of influential friends, however, the mathematician and teacher was spared. He remained in England throughout Cromwell's reign, despite offers from foreign rulers who had heard of his fame.

Oughtred died on June 30, 1660, at the parsonage in Albury. Tradition holds that he died of joy at learning that King Charles II had returned to England from Scotland and been restored to the English throne. Books Complete Dictionary of Scientific Biography COPYRIGHT 2008 Charles Scribner's Sons OUGHTRED, WILLIAM (b. Eton, Buckinghamshire, England, 5 March 1575; d. Albury, near Guildford, Surrey, England, 30 June 1660), mathematics Oughtred’s father was a scrivener who taught writing at Eton and instructed his young son in arithmetic. Oughtred was educated as a king’s scholar at Eton, from which he proceeded to King’s College Cambridge, at the age of fifteen. He became a fellow of his college in 1595, graduated B. A. in 1596, and was awarded the M. A. 1600. Ordained a priest in 1603, Oughtred at once began his ecclesiastical duties, being presented with the living of Shalford, Surrey.

Five years later he became rector of Albury and retained this post until his death. Despite his parochial duties he continued to devote considerable time to mathematics , and in 1628 he was called upon to instruct Lord William Howard, the young son of the earl of Arundel. In carrying out this task he prepared a treatise on arithmetic and algebra. This slight volume, of barely 100 pages, contained almost all that was then known of these two branches of mathematics; it was published in 1631 as Clavis mathematicae. Oughtred’s best-remembered work. the Clavis exerted considerable influence in England and on the Continent and immediately established him as a capable mathematician. Both Boyle and Newton held a very high opinion of the work.

In a letter to Nathaniel Hawes, treasurer of Christ’s Hospital, dated 25 May 1694 and entitled “A New Scheme of learning for the Mathematical Boys at Christ’s Hospital,” Newton referred to Oughtred as “a man whose judgement (if any man’s) may be relyed on.” In Lord king’s Life of Locke we read “ The best Algebra yet extant is Oughtred’s” (I227). John Aubrey, in Brief Lives, maintained that Oughtred was more famous abroad for his learning than at home and that several great men came to England for the purpose of meeting him (II, 471). John Wallis dedicated his Arithmetica infinitorum (1655) to Oughtred. A pupil of Oughtred, Wallis never wearied of sounding his praises. In his Algebra (1695) he wrote. The Clavis doth in as little room delvier as much as the fundamental and useful parts of geometry (as well as of arithmetic and algebra) as any book I know, “ and in its preface he classed Oughtred with the English mathematician Thomas Harriot.

The Clavis is not easy reading. The style is very obscure, and rules are so involved as to make them difficult to follow. Oughtred carried symbolism to excess, using signs to denote quantities, their powers, and the fundamental operations in arithmetic and algebra. chief among these were X for multiplication,⊐ for “greater than”;⊏for “less than”; and ~ for difference between. “Ratio was denoted by a dot; proportion, by∷. Thus the proportion A: B=α: β was written A · B ∷α· β. Continued proportion was written ∺ Of the maze of symbols employed by Oughred, only those for multiplication and proportion are till used. Yet, surposingly, there is a complete absence of indices or exponents from his work. Even in later editions of the Clavis, Oughtred used Aq, Ac Aqq, Aqc, Acc, Aqcc, Accc, Aqqcc,to denote successive powers of A up to the tenth. In his Géométrie (1637) Descartes had introduced the notation xn but restricted its use to cases in which n was a positive whole number.

Netwon extended this notation to include fractional and negative indices. These first appeared in a letter to Oldenburg for transmission to Leibniz— the famous Epistola Prior of June 1676— in which Newton illustrated the newly discovered binomial theorem. In La disme, a short tract published in 1585, Simon Stevin had outlined the principles of decimal fractions. Although a warm admirer of Stevin’s work, Oughtred avoided his clumsy notation and substituted his own, which, although an improvement, was far from satisfactory. He did not use the dot to separate the decimal from the whole number, undoubtedly because he already used it to denote ratio; instead, he wrote a decimal such as 0.56 as 0/5̲6̲. Oughtred is generally regarded as the inventor of the circular and rectilinear slide rules. Although the former is described in his Circles of Proportion and the Horizontal Instrument (1632), a description of the instrument had been published two years earlier by one of his pupils, Richard Delamain, in Grammelogie, or the Mathematical Ring. A better quarrle ensued between the two each claiming priority in the invention.

There seems to be no very good reason why each should not be credited as an independent inventor. Oughtred’s claim to priority in the invention of the rectilinear slide rule, however, is beyond dispute, since it is known that he had designed the instrument as early as 1621. In 1657 Oughtred published Trigonometria, a work of thirty-six pages dealing with both plane and spherical triangles. Oughtred made free use of the abbreviations s for sine t for tangent , se for secant sco for sine of the complement (or cosine), tco for secant cotangent, and seco for cosecant. The work also contains tables of sinces, tangents, and secants to seven decimal places as well as tables of logrithms, also to seven places. It is said that Oughtred, a staunch royalist, died in a transport of joy on hearing the news of the restoration of Charles II. BIBLIOGRAPHY I. Original Works.

Oughtred’s chief writing is Arithmeticae in numeris et speciebus institutio…quasi clavis mathematicae est (London, 1631); 2nd ed., Clavis mathematicae (London, 1648). English translations were made by Robert Wood (1647) and Edmond Halley (1694) Subsequent Latin eds,. appeared at Oxford in 1652, 1667 and 1693. His other works are The Circles of Proportion and the Horiziontal Instrument, W. Forster, trans, (London, 1632), a treatise on navigation; The Description and Use of the Double Horizional Dial (London, 1636); A Most Easy Way for the Delination of plain Sunidals, Only by Gometry(1647); The solution of All Spherical Triangles (Offord, 1651); Description and use of the General Horological Ring and the Double Horizotal Dial(London, 1653); Trignometria (London, 1657), trans by R.

Stokes as Trignometric (London, 1675); and Canones sinuum, tangentium, sectantium et logarithmorum (London, 1657). A collection of Oughtred’s papers, mainly on mathematical subjects, was published posthumously under the direction of Charles Scarborough as Opuscula mathematica hactenus inedita (Oxford, 1677). II. Secondary Literature. On Oughtred or his work see John Aubrey, Briey Lives Andrew Clark, ed. (Oxford, 1898), II, 106, 113–114, W. W. R.

Ball,A History of the study of Mathematics at Cambridge (Chicago-London, 1916); Florian Cajori, William Oughtred, a Great Sevententh Century Teacher of Mathematics (Chicago-London, 1916); Moritz Cantor,volesungne über Geschite der Mathematick, 2nd, ed., II (Liepzig, 1913), 720–721; charles Hutton, Philosophical and Mathematical Dictionary, new (London, 1918), II, 141–142; and S. J. Riguaud, ed., Correspondence of scientific Men of the seventeenth Century, I(Oxford, 1841), 11, 16,66. J. F. Scott The Galileo Project Born: Eton, Buckinghamshire, 5 March 1575 Died: Albury, near Guildford, Surrey, 30 June 1660 Dateinfo: Dates Certain 2. Father Occupation: Cleric, Schoolmaster The Rev. Benjamin Oughtred is said to have been a scribe\amanuensis who taught writing.

In the accounts the teaching of writing seems to dominate, rather than employment as a scribe. That is, clear handwriting figures in Oughtred's life, and is traced back to his father's influence; I don't think the accounts were trying to describe the father's source of income. No one even talks about the fact he was "the Rev." Mr. Oughtred; I am assuming that this had meaning. His son did follow that calling. No information on financial status. 3. Nationality Cambridge University, King's College, 1592-1600; B.A., 1596; M.A., 1600. 5. Religion Affiliation: Anglican Oughtred was ordained in 1603 and spent his life as an Anglican clergyman. During the Civil War he was thoroughly royalist in outlook, and would have been sequestered except for influence brought to bear on his behalf. 6. Scientific Disciplines Primary: Mathematics Subordinate: Alchemy Clavis mathematicae, 1631, on arithmetic and algebra, composed for instruction of his pupil, the son of the Earl of Arundel.

Circles of Proportion and the Horizontal Instrument, 1632, describing the first slide rules and also sundials. Easy Way of Delineating Dials by Geometry, composed c. 1598, published only in the English Clavis in 1647. Trigonometrie, 1657. Josten is explicit in naming Oughtred an alchemist. 7. Means of Support Fellow of King's College, Cambridge, 1595-1603. Vicar of Shalford, Surrey, 1604. Rector of Albury, Surrey, 1610-60. Income of ï¿½100. Oughtred was a very active tutor of mathematics: 1620s-60. He himself asserts, and considerable other testimony confirms, that he refused to accept any money in return. Oughtred was a clergyman who was adequately supported in his own view. He does not appear to have aspired for more. Resided in the London house of the Earl of Arundel for some years in 1620s as tutor to the Earl's son. 8.

Patronage Types: Aristrocrat, Gentry The Earl of Arundel strongly supported his study, and encouraged him to publish his work. Oughtred dedicated Clavis, composed for the Earl's son, to the Earl. Charles Cavendish is said to have requested the publication urgently; just what his relationship to Oughtred was otherwise is not mentioned. In 1646 Oughtred, a royalist, was about to be sequestered by the Puritan government. Sir Bulstrode Whitelocke and others exerted influence that allowed him to be spared. The Grand Duke of Florence invited him to Florence and offered him ï¿½500 per annum in 1640s. I will not list this offer, which Oughtred declined; it is probably a myth in any case. 9. Technological Involvement Types: Applied Mathematics, Instruments, Cartography He is generally regarded as the inventor of both the circular and the rectilinear slide rule. He invented a method of calculating logs, and he wrote a short tract on the solution of spherical triangles by the planisphere without the tedious labor of trigonometric calculations.

Composed An Easy Way of Delineating Dials by Geometry about 1598. Shortly thereafter he composed a tract on drawing a dial on any plane surface however inclined (published with Circles of Proportion, 1632); in the tract he described an instrument, which he later called the horizontal instrument, a time-showing device and a limited model (on a plane) of the heavens, which allowed the position of the sun to be determined graphically and also made possible the delineation of a dial on any plane surface. He also wrote a small piece on watchmaking. Oughtred is said also to have practiced as a surveyor. 10. Scientific Societies Memberships: None Informal Connections: Pupils: Seth Ward, Jonas More, Charles Scarborough, John Wallis, Christopher Wren, Mr. Smethwyck, Mr. Austin, Thomas Henshawe, William Forster, Arthur Haughton, Robert Wood, William Gascoigne, and many others. Correspondence with Henry Briggs, Edmund Gunter, Robert Keylway, Dr. Lloyd, and some his (Oughtred's) pupils.

Sources Dictionary of National Biography (repr., London: Oxford University Press, 1949-50), 14, 1250-2. O.L. Dick, ed., Aubrey's Brief Lives, (Ann Arbor, 1957), pp.222- 5. Florian Cajori, William Oughtred, a Great Seventeenth-Century Teacher of Mathemetics, (Chicago, 1916). A.J. Turner, "William Oughtred, Richard Delamain and the Horizontral Instrument in Seventeenth Century England," Annali dell'Istituto e Museo di Storia della Scienze, Firenze, 6.2 (1981), 99-125. Elias Ashmole, 5 vols. ed. with a biographical introduction by C.H. Josten, (Oxford, 1966), 1, 109. Compiled by: Department of History and Philosophy of Science Indiana University

Question: Which device did William Oughtred invent in 1621?
Answer: The Slide Rule