Adriaan Anthonisz

{{short description|Dutch mathematician}}

File:Mr Adriaan Anthonisz John Bier Noorderkade Alkmaar.JPG

Adriaan Anthonisz (also known as Adriaen Anthonisz of Alcmaer) (1527–1607){{cite book|author=Charles Joseph Singer|title=Studies in the History and Method of Science: Singer, Charles. Greek biology and its relation to the rise of modern biology|url=https://books.google.com/books?id=HbFXAAAAYAAJ|year=1921|publisher=Clarendon Press}}{{cite book|author1=J.L. Berggren|author2=Jonathan Borwein|author3=Peter Borwein|title=Pi: A Source Book|url=https://books.google.com/books?id=QhbrBwAAQBAJ&pg=PA291|date=13 January 2014|publisher=Springer|isbn=978-1-4757-4217-6|pages=291–}}{{cite book|title=Mathematics Magazine|url=https://books.google.com/books?id=liw5AAAAIAAJ|year=1949|publisher=Mathematical Association of America}} was a Dutch mathematician, surveyor, cartographer, and military engineer who specialized in the design of fortifications. As a mathematician Anthonisz calculated in 1585 the ratio of a circle's circumference to its diameter, which would later be called pi.

Life

Anthonisz served as burgomaster (mayor) of Alkmaar in the Netherlands from 1582.{{cite book|author=Christopher Duffy|title=Siege Warfare: The Fortress in the Early Modern World 1494-1660|url=https://books.google.com/books?id=G5K8SKVbm10C&pg=PA82|date=15 April 2013|publisher=Routledge|isbn=978-1-136-60786-8|pages=82–}}

Adriaan fathered two sons, and named them both Metius (from the Dutch word meten, meaning 'measuring', 'measurer', or surveyor). They each became prominent members of society.{{cite book|author1=Harold John Cook|author2=Sven Dupré|title=Translating Knowledge in the Early Modern Low Countries|url=https://books.google.com/books?id=kcHjpoAHXq0C&pg=PA273|year=2012|publisher=LIT Verlag Münster|isbn=978-3-643-90246-7|pages=273–}} Adriaan Metius (9 Dec 1571 – 6 Sep 1635) was a Dutch geometer and astronomer. Jacob Metius worked as an instrument-maker and a specialist in grinding lenses and applied for patent rights for the telescope a few weeks after Middelburg spectacle-maker Hans Lippershey tried to patent the same device.{{Cite web|url=http://onthisday.org|title=Non-Existent Domain|website=onthisday.org|access-date=2016-04-20}}

Career

In 1585 Anthonisz discovered that the ratio of a circle's circumference to its diameter, later called pi, approximated the fractional value of {{math|{{sfrac|355|113}}}}. His son Adriaan Metius later published his father's results, and the value {{math|{{sfrac|355|113}}}} is traditionally referred to as Metius' number'.{{cite web|url=http://kr.cs.ait.ac.th/~radok/math/mat4/m41.htm |title=M41 |access-date=August 30, 2005 |url-status=dead |archive-url=https://web.archive.org/web/20051101013921/http://kr.cs.ait.ac.th/~radok/math/mat4/m41.htm |archive-date=November 1, 2005 }}{{cite book|author=Royal Institution of Great Britain|title=The Journal of the Royal Institution of Great Britain|url=https://archive.org/details/journalroyalins00britgoog|year=1831|publisher=John Murray|pages=[https://archive.org/details/journalroyalins00britgoog/page/n348 320]–}}

He is regarded as one of the first military engineers to apply the principles of the Dutch fortification system.{{citation |url=http://dissertations.ub.rug.nl/FILES/faculties/arts/2001/e.a.koster/h9.pdf |title=Fortificate – Ideaal en Werkelijkheid |pages=217–218 |last=Koster |publisher=Dissertations.ub.rug.nl |access-date=2016-04-11 |archive-url=https://web.archive.org/web/20111118111746/http://dissertations.ub.rug.nl/FILES/faculties/arts/2001/e.a.koster/h9.pdf |archive-date=2011-11-18 |url-status=dead }}

Some of his professional accomplishments included mapping the Berger lake and expanding and fortifying Naarden and Muiden.{{cite web|url=http://galileo.rice.edu/Catalog/NewFiles/anthoniz.html|title=The Galileo Project|publisher=Rice University|access-date=9 May 2016}}

References