Editing Compass (section)

===Artificial compass===
[[File:Model Si Nan of Han Dynasty.jpg|thumb|Model of a lodestone compass from [[Han dynasty]]]]
Some claims state that the first compasses in ancient [[Han dynasty]] China were made of [[lodestone]], a naturally magnetized ore of iron.<ref name="cambridge1">{{cite book |last=Lowrie |first=William |url=https://archive.org/details/fundamentalsgeop00will |title=Fundamentals of Geophysics |publisher=Cambridge University Press |year=2007 |isbn=978-0-521-67596-3 |edition=2nd |location=London |pages=[https://archive.org/details/fundamentalsgeop00will/page/n290 281] |quote=Early in the Han dynasty, between 300 and 200 BC, the Chinese fashioned a rudimentary compass out of lodestone&nbsp;... This compass may have been used in the search for gems and in the selection of sites for houses&nbsp;... Their directive power led to the use of compasses for navigation... |url-access=limited}}</ref><ref name="guarnieri 7-1">{{Cite journal|last=Guarnieri|first=M.|year=2014|title=Once Upon a Time, the Compass|journal=IEEE Industrial Electronics Magazine|volume=8|issue=2|pages=60–63|doi=10.1109/MIE.2014.2316044|s2cid=11949042}}</ref> The earliest mention of a needle's attraction appears in a work composed between 20 and 100 AD, the ''[[Lunheng]]'' (''Balanced Inquiries''): "A lodestone attracts a needle."<ref>In the section "[https://archive.org/stream/lunheng02wang#page/350/mode/1up A Last Word on Dragons]" ({{lang|zh|亂龍篇}} ''Luanlong'') of the ''[[Lunheng]]'': "[[Amber]] takes up straws, and a load-stone attracts needles" ({{lang|zh|頓牟掇芥，磁石引針}}).</ref> In the 2nd century BC, Chinese [[Geomancy|geomancers]] were experimenting with the magnetic properties of lodestone to make a "south-pointing spoon" for divination. When it is placed on a smooth bronze plate, the spoon would invariably rotate to a north–south axis.<ref>{{Cite book |title=Echoes from Old China: Life, Legends, and Lore of the Middle Kingdom |last=Tom |first=K. S. |publisher=University of Hawaii Press |year=1989 |pages=108}}</ref><ref>{{Cite book |title=Chinese Fans: Artistry and Aesthetics  |last= Qian  |first= Gonglin |publisher=Long River Press |year=2000 |isbn= 978-1592650200 |pages=98}}</ref><ref>{{Cite book |title=The History of China: (The Greenwood Histories of the Modern Nations) |last=Curtis Wright  |first=David |publisher=Greenwood Publishing Group |year=2001 |pages=42}}</ref> While this has been shown to work, archaeologists have yet to discover an actual spoon made of magnetite in a Han tomb.<ref>Joseph Needham, ''Clerks and Craftsmen in China and the West: Lectures and Addresses on the History of Science and Technology''. Cambridge: University Press, 1970, p. 241.</ref> A similar compass that used an iron fish to point north in a vessel of oil appeared in [[South India|Southern India]] in the 4th century AD.<ref>{{cite book |title=Encyclopaedia of the History of Science, Technology, and Medicine in Non-Western Cultures |publisher=Springer |year=2008 |isbn=978-1-4020-4559-2 |editor=Helaine Selin |page=197}}</ref><ref>{{cite book |url=https://books.google.com/books?id=HUAPAAAAIAAJ&q=%22matsya+yantra%22 |title=The American Journal of Science |year=1919 |accessdate=2009-06-30}}</ref> 

Later compasses were made of iron needles, magnetized by striking them with a lodestone, which appeared in China by 1088 during the [[Song dynasty]], [[Dream Pool Essays|as described]] by [[Shen Kuo]].<ref name=merrill>{{cite book|last=Merrill|first=Ronald T.|title=The Earth's magnetic field: Its history, origin and planetary perspective|year=1983|publisher=Academic press|location=San Francisco|isbn=978-0-12-491242-7|page=[https://archive.org/details/earthsmagneticfi00merr/page/1 1]|edition=2nd printing|author2=McElhinny, Michael W.|url=https://archive.org/details/earthsmagneticfi00merr/page/1}}</ref> Dry compasses began to appear around 1300 in [[Medieval Europe]] and the [[Islamic world]].<ref name="Lane, p. 615"/><ref name=OEPST /> This was supplanted in the early 20th century by the liquid-filled magnetic compass.<ref name="W. H. Creak 238-239">{{cite journal|author=Creak, W.H. |title=The History of the Liquid Compass|journal=The Geographical Journal|volume=56|issue=3 |year=1920|pages=238–239|doi=10.2307/1781554|jstor=1781554|bibcode=1920GeogJ..56..238C }}</ref>