Happy Earth Day!


Happy Earth Day!  Today, April 22, Earth Day celebrations are occurring throughout the United States as well as around the world.  This year’s theme, Green Cities, focuses on sustainable communities.  Denis Hayes was the first coordinator of Earth Day, an environmental “teach-in” held on April 22, 1970.  In the first Earth Day participants from two thousand colleges and universities, roughly ten thousand primary and secondary schools, and hundreds of communities across the United States “brought 20 million Americans out into the spring sunshine for peaceful demonstrations in favor of environmental reform.”  He founded the Earth Day Network in Washington, DC and expanded it to 192 countries.  Time Magazine named him “Hero of the planet” in 1999.  His mentor, former US Senator from Wisconsin, Gaylord Nelson, originated the idea 44 years ago, in 1970, to promote and support responsible protection of our environment, the Earth. Gaylord Nelson hired Denis Hayes, a student attending the Kennedy School of Government at Harvard University to organize the first Earth Day. In 1995, Nelson was awarded the Presidential Medal of Freedom in recognition of his work.

The first to propose an international day to honor the Earth was peace activist John McConnell. His vision, formed at a UNESCO conference on the environment in 1969, included a celebration to be held on the first day of spring in the Northern Hemisphere: March 21, McConnell’s proposal led to a proclamation signed by Secretary General U Thant at the United Nations in 1971, initiating an annual Earth Day on April 22nd.  McConnell later founded the Earth Society in 1976 with anthropologist Margaret Mead.


April 22 Is Earth Day: What it Means, (2014) from http://usparks.about.com/od/conservationpreservation/a/earth_day.htm

Brosnan, Kathleen A.  Encyclopedia of American Environmental History Volume II.  New York: Facts on File, Inc.  An imprint of Infobase Publishing, 2011.  Engineering Library Folio GE 150 .E53 2011 V.2 http://infohawk.uiowa.edu/F/?func=find-b&find_code=SYS&local_base=UIOWA&request=005765304

Earth Day Extravaganza Sheds Its Humble Roots (April 22, 1990) from http://www.nytimes.com/1990/04/22/us/earth-day-extravaganza-sheds-its-humble-roots.html?scp=2&sq=%22earth+day%22&st=nyt

Earth Day History:  The History of Earth Day (2014) from http://environment.about.com/od/environmentalevents/a/twoearthdays.htm

Gorman, Hugh S. The Story of N:  A Social History of the Nitrogen Cycle and the Challenge of Sustainability.  N.J.  : Rutgers University Press, 2013.  Engineering Library TD196.N55 G67 2013.  http://infohawk.uiowa.edu/F/?func=find-b&find_code=SYS&local_base=UIOWA&request=007232308

Khale, Lynn R, and Eda Gurel-Atay, editors.  Communicating Sustainability for the Green Economy. New York: M.E. Sharpe, 2014.  Engineering Library HC79. E5.C61236 2014. http://infohawk.uiowa.edu/F/?func=find-b&find_code=SYS&local_base=UIOWA&request=007444474

Taback, H.J. Environmental Ethics and Sustainability: A Casebook for Environmental Professionals. Florida, Boca Raton: CRC Press 2014. Engineering Library GE42. T33 2014. http://infohawk.uiowa.edu/F/?func=find-b&find_code=SYS&local_base=UIOWA&request=007366984

United Nations Framework Convention on Climate Change, (2014) from https://unfccc.int/2860.php

Who Invented Earth Day? ( 2014)  from http://environment.about.com/od/earthday/f/who-invented-earth-day.htm





April 15th is Eraser Day!


April 15th is National Rubber 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

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/