April 15th is Eraser Day!

April 15th is Eraser Day!


When  celebrating the invention of the eraser, the names and stories of several European scientists intertwine: Frenchman Charles Marie de la Condamine, Portuguese Jean Hyacinthe de Magellan, and Englishmen Edward Nairne and Joseph Priestley are collectively responsible for its discovery and use.

Condamine was sent to South America in 1735 by the French Academy of Science to calculate the diameter of the Earth at the equator.  In his travels through Peru, Ecuador, and Brazil, he was fascinated by caoutchouc, a milky white elastic substance produced under the bark of a tropical tree.  He returned with samples in 1745.  By 1752, Jean Hyacinthe de Magellan, a Portuguese scientist who corresponded with internationally known scientists of his day, is thought to have been the person responsible for suggesting that caoutchouc be used as an eraser in the Proceedings of the French Academy.  Until that time, pieces of bread had been used to eliminate marks on paper. According to Inventors and Inventions, Sir John Priestly noted the erasing properties of vegetable gum:  “I have seen a substance excellently adapted to the purpose of wiping from paper the mark of black pencil lead.” By 1778, Priestley suggested that caoutchouc be called “rubber” for its properties. A decade later, by 1790, the word “eraser” was in use and referred to the object used to remove pencil marks.

In 1839, American Charles Goodyear developed and patented a process to keep the rubber material from rotting.  The process, vulcanization which is named after the Roman god of fire, cured and stabilized the rubber.  Today, erasers are made from synthetic rubber or vinyl.  The engineering and production process involved can be seen in a short You Tube video by the Staedtler Corporation http://youtu.be/FocX6Fews6k or in the article Eraser:  Raw Materials and Manufacturing Process are described in detail at a site called: http://www.madehow.com/Volume-5/Eraser.html



Hyacinthe Magellan (2014) retrieved from  http://www.amphilsoc.org/exhibits/magellan/magellan.htm

Innovateus, Edward Nairne (2006-2013) retrieved from  http://www.innovateus.net/inventor/edward-nairne

Online Etymology Dictionary (2001-2014) retrieved from http://etymonline.com/index.php?allowed_in_frame=0&search=eraser&searchmode=none

Colonel Percy Harrison Fawcett, Charles Marie De La Condamine (1999) http://www.phfawcettsweb.org/condam.htm


Combination of Lead-pencil and eraser (US 19783A) https://www.google.com/patents/US19783?dq=eraser&hl=en&sa=X&ei=_GVNU4qLL4KE2wXRhIHQAg&ved=0CDUQ6AEwAA















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Leonardo da Vinci the Engineer

Leonardo Da Vinci's inventions

Come see the exhibit on Leonardo da Vinci: The Engineer at the Lichtenberger Engineering Library.  The exhibit includes models of some of his engineering feats:  a catapult and a multiple sling designed as war machines to hurl stones, a paddleboat and a great kite.  Stop by and see pictures of his underwater breathing machine, a steam cannon, a gigantic crossbow and the Vitruvian man.

Included in the exhibit case are facsimiles from the University’s Special Collections of da Vinci’s original manuscripts printed from the collection of the Institute de France.  Twelve manuscripts written between 1492 and 1516 were brought back to Italy by Francesco Melzi, his favorite pupil, after da Vinci’s death.  These facsimiles feature over five thousand pages of drawings and notes in his characteristic “mirror-image” hand-writing, running from right. The sections on display in the case are those related to:  the military art, optics, geometry, the flight of birds and hydraulics.


One of Da Vinci’s famous drawings is of the Vitruvian Man, a drawing created in 1490, is accompanied by notes based on the work of the architect Vitruvius and Book III of his treatise De Architectura.  Vitruvius the architect described the human body with having ideal proportions.  The drawing, pen and ink on paper, depicts a male figure in a square within a circle.  The drawings sometimes referred to as the “Proportions of Man,” and named in honor of the architect Vitruvius, represent da Vinci’s blend of art and science.  Encyclopaedia Brittanica online states that da Vinci “believed the workings of the human body to be an analogy for the workings of the universe.”


Those of you interested in hydraulics may know about Enzo Macagno.  In 1960, Macagno became interested in studies of the history of fluid mechanics and the life of da Vinci.  Along with his colleague and late wife, Matilde, Macagno became an international expert on da Vinci, publishing numerous articles and IIHR monographs on the interpretation, analysis, and synthesis of da Vinci’s codices and manuscripts as they relate to fluid-flow and transport phenomena.  You will find more information in the exhibit case and two monographs from Special Collections on Macagno’s work.

This is just a sampling of what can be seen at the Lichtenberger Engineering Library’s Leonardo Da Vinci: The Engineer exhibit. Stop by to learn more!



Capra, Fritjof. The Science of Leonardo.  New York: Doubleday,2007. Engineering Library Q143.L5 C37 2007 http://infohawk.uiowa.edu/F/?func=find-b&find_code=SYS&local_base=UIOWA&request=004251437

da Vinci, Leonardo, 1452-1519.  Leonard da Vinci: scientist, inventor, Artist.  Ostfildern-Ruit [Germany]: Verlage Gerd Hatje, 1997. Engineering Library N6923.L33 A4 1997 http://infohawk.uiowa.edu/F/?func=find-b&find_code=SYS&local_base=UIOWA&request=007162629

Kemp, Martin.  Leonard Da Vinci Experience, Experiment and Design.  Oxford: Princeton University Press, 2006. Art Oversize FOLIO N6923.L33 K449 2006. http://infohawk.uiowa.edu/F/?func=find-b&find_code=SYS&local_base=UIOWA&request=003637253

Laurenza, Domenico.  Leonardo on Flight.  Baltimore: The John Hopkins University press,2004. Engineering Library TL540.L4 L38 2007. http://infohawk.uiowa.edu/F/?func=find-b&find_code=SYS&local_base=UIOWA&request=004220622

Moon, Francis C.The Machines of Leonardo Da Vinci and Franz Reuleaux.  New York: Springer, 2007. Engineering Library TJ 230 .M66 2007. http://infohawk.uiowa.edu/F/?func=find-b&find_code=SYS&local_base=UIOWA&request=004382572

Museo Nazionale Della Scienza E Della Technologia Leonardo Da Vinci.(2014).Retrieved from http://www.museoscienza.org/english/leonardo/manoscritti/

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Xpress Class Wednesday April 2nd–Endnote Basic

April 2nd – Endnote Basic (30 minutes) 

Introduction to an online citation management system that is free for everyone at the University of Iowa. This is replacing RefWorks which the University will no long be supporting as of December 2014.   Endnote helps you to manage all your references for a paper (or many papers) as well as create the incite citations and bibliographies in a wide variety of formatting styles.  Taught by Steve Ostrem (Reference and Instruction Librarian, Main Library) The web version of Endnote Basic will be taught not the full client version!

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Come Celebrate Pi Day 3.14,1:59!


On March 14 at 1:59 pm we gather together to celebrate the most famous and mysterious of numbers.  That Pi is defined as the ratio of the circumference of a circle to its diameter seems simple enough but Pi turns out to be an “irrational number.”  Computer scientists have calculated billions of digits of pi, starting with 3.14159265358979323…, no recognizable pattern emerges in the digits.  Scientists could continue calculating the next digit all the way to infinity and still have no idea which digit might emerge next.  To these facts can be added that March 14 is also Einstein’s birthday.

Pi is a number that has fascinated scholars for 4,000 years.  The mathematical history of pi comes from around the world.  In 1900 B.C., the Babylonians calculated the area of the circle by taking 3 times the square of its radius.  One Babylonian tablet (ca 1900-1680 B.C.) indicates a value of 3.125 for pi, which is a close approximation. Around 1650 B.C., the Rhind Papyrus, a famous document of the Egyptian Middle Kingdom, also calculated the area of a circle which gave the approximate value of 3.1605.



In 250 B.C., the Greek mathematician Archimedes calculated the circumference of a circle to its  diameter.  Archimedes  value , was not only more accurate; it was the first theoretical rather than measured calculations of pi.  Archimedes knew that he had not found the value of pi but only an approximation. He used a fairy simply geometrical approach for his calculations.  See how he did it by launching the interactive model on this pbs.org site: http://www.pbs.org/wgbh/nova/physics/approximating-pi.html



Zu Chongzhi (429-501 AD?) was a Chinese mathematician and astronomer, who was not familiar with Archimedes method. He calculated the value of the ratio of the circumference of a circle to its diameter. Unfortunately, his book has been lost so very little is known of his work.

In 1761, a Swiss mathematician Johann Heinrich Lambert (1782-1777) proved the irrationality of pi.  An irrational number is a number that cannot be made into a fraction where the decimal never ends or repeat sequences.

By 1882, F. Lindeman proved that pi was transcendental, that is, that pi is not the root of any algebraic equation with rational coefficients.  This discovery proved that you can’t “square the circle” which was a problem that vexed many mathematicians up to that time.  Another fascination for mathematicians throughout history was to calculate the digits of pi, but until computers, less than 1,000 digits had been calculated.  With the calculations of the computer, millions of digits have been calculated.


Adiran, Y. E. O.  The Pleasures of Pi, e and Other Interesting Numbers.  Singapore: World Scientific Pub., c2006.  Engineering Library QA95 .A2 2006

Alsina, Claudi.  Icons of Mathematics:  An Exploration of Twenty Key Images. Washington, D.C.:  Mathematical Association of America c2011.   http://site.ebrary.com/lib/uiowa/Doc?id=10728529

Beckman, Petr.  The History of Pi. Boulder: Colorado: The Golem Press, 1977.  Main Math Collection QA484 .B4 1977

Chongzhi, Zu.  Encyclopedia Britannica.  Encyclopedia Britannica Online. Encyclopedia Britannica Inc., 2014.  Web, 10 March 2014.    Http://wwwbritannica.com / EBchecked/topic/1073884/Zu-Chongzhi.   Main Reference Collection AE5 .E363 2010

Exploratorium. (2014). Pi Day. Retrieved from http://www.exploratorium.edu/pi/

Gillings, R. Mathematics in the Time of the Pharaohs. Boston, MA: MIT Press, 89-103, 1972.  Main Math Collection QA27.E3 G52 

Gardner, Milo. “Rhind Papyrus.” From MathWorld–A Wolfram Web Resource, created by Eric W. Weisstein. http://mathworld.wolfram.com/RhindPapyrus.html

A facsimile of this papyrus can also be found at the
Main Oversize FOLIO PJ1681 R5 1927
Main Math Collection FOLIO PJ1681 R5 1927

Hobson, Ernest William.  Squaring the Circle and Other Monographs. New York: Chelsea, 1953.  Main Math Collection QA467 .H62 1953 

KHANACADEMY. (2014). A Song About A Circle Constant. Retrieved from https://www.khanacademy.org/math/recreational-math/vi-hart/pi-tau/v/a-song-about-a-circle-constant

Libeskind, Shlomo.  Euclidean and Transformational Geometry: A Deductive Inquiry. Sudbury, Mass.:  Jones and Bartlett Publishers, c 2008. Engineering Library QA453 .L53 2008 

Mackenzie, D. “Fractions to Make an Egyptian Scribe Blanch.” Science 278, 224, 1997.

McCall, Martin W.  Classical Mechanics:  From Newton to Einstein: A Modern Introduction.  Hoboken, NJ: Wiley, 2010.  Engineering Library QC125.2 .M385 2011 

Robins, G. and Shute, C. The Rhind Mathematical Papyrus: An Ancient Egyptian Text. New York: Dover, 1990. Main Math Collection QA30.3 .R63 1987 

Weingardt, Richard.  Circles in The Sky:  The Life and Times of George Ferris.  Reston, VA,: American Society of Civil Engineers, C.2009.  Engineering Library TA140.F455 W45 2009


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Xpress Class Tomorrow Wednesday March 5th–Endnote Basic (30 minutes)

Introduction to an online citation management system that is free for everyone at the University of Iowa.   It helps you to manage all your references for a paper (or many papers) as well as create the incite citations and bibliographies in a wide variety of formatting styles.  Taught by Amy Blevins (Clinical Education Librarian, Hardin Library for the Health Sciences) http://goo.gl/N9eS1v

The web version of Endnote Basic will be taught not the full client version!

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TODAY! Library Xpress: Standards

The Engineering Library is offering a 15 minutes class TODAY at 2:30 pm in the Library Computer Classroom (2001C SC).

Introduction to standards, regulations and specifications.  Learn how to access a wide variety of standards including ASTM, ISO, ADA, NFPA (Fluid), and the US Code of Federal Regulations.  Featuring a new database, TechStreet, to gain electronic access to these standards and more.   Taught by Kari Kozak (Head, Lichtenberger Engineering Library)Want to learn more about how to use Standards? Visit 2001C SC at 2:30pm Wednesday February 26 for a 15min class! http://goo.gl/N9eS1v

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