Sunstone (medieval) – Wikipedia

Historical navigational help

The sunstone (Icelandic: sólarsteinn) is a sort of mineral attested in a number of thirteenth–14th-century written sources in Iceland, certainly one of which describes its use to find the Sun in a very overcast sky. Sunstones are additionally talked about within the inventories of a number of churches and one monastery in 14th–Fifteenth-century Iceland and Germany.
A idea exists that the sunstone had polarizing attributes and was used as a navigational instrument by seafarers within the Viking Age.[1] A stone present in 2002 off Alderney, within the wreck of a Sixteenth-century warship, might lend proof of the existence of sunstones as navigational gadgets.[2]
Sources[edit]
One medieval supply in Iceland, “Rauðúlfs þáttr“,[3][4] mentions the sunstone as a mineral by way of which the solar could possibly be situated in an overcast and snowy sky by holding it up and noting the place it emitted, mirrored or transmitted gentle (hvar geislaði úr honum).[5] Sunstones are additionally talked about in Hrafns saga Sveinbjarnarsonar [Wikidata] (thirteenth century)[6] and in church and monastic inventories (14th–Fifteenth century) with out discussing their attributes. The sunstone texts of Hrafns saga Sveinbjarnarsonar had been copied to all 4 variations of the medieval hagiography Guðmundar saga góða.[7]
The outline in “Rauðúlfs þáttr” of the usage of the sunstone is as follows:
In Icelandic: |
Thorsteinn Vilhjalmsson translation: |
Allegorical nature of the medieval texts[edit]
Two of the unique medieval texts on the sunstone are allegorical. Hrafns saga Sveinbjarnarsonar accommodates a burst of purely allegorical materials related to Hrafn’s slaying. This entails a celestial imaginative and prescient with three extremely cosmological knights, recalling the horsemen of the Apocalypse.[6] It has been advised[10] that the horsemen of Hrafns saga include allegorical allusions to the winter solstice and the four elements as an omen of Hrafn’s loss of life, the place the sunstone additionally seems.
“Rauðúlfs þáttr”, a story of Saint Olav, and the one medieval supply mentioning how the sunstone was used, is a completely allegorical work.[11] A spherical and rotating home visited by Olav has been interpreted as a mannequin of the cosmos and the human soul,[12] in addition to a prefiguration of the Church.[13] The intention of the creator was to realize an apotheosis of St. Olav, by inserting him within the symbolic seat of Christ.[11] The home belongs to the genre of “abodes of the solar,” which appeared widespread in medieval literature.[4] St. Olav used the sunstone to verify the time reckoning ability of his host proper after leaving this allegorical home. He held the sunstone up towards the snowy and fully overcast sky and famous the place gentle was emitted from it (the Icelandic phrases used don’t make it clear whether or not the sunshine was mirrored by the stone, emitted by it or transmitted by it). It has been advised[10][14] that in “Rauðúlfs þáttr” the sunstone was used as an emblem of the Virgin, following a widespread custom during which the virgin birth of Christ is in contrast with glass letting a ray of the solar by.[15]
The allegories of the above-mentioned texts exploit the symbolic worth of the sunstone, however the church and monastic inventories, nevertheless, present that one thing known as sunstones did exist as bodily objects in Iceland. The presence of the sunstone in “Rauðúlfs þáttr” could also be fully symbolic[17] however its use is described in enough element to point out that the thought of utilizing a stone to seek out the solar’s place in overcast situations was commonplace.[10]
Chance of sunstones for orientation and navigation[edit]
Danish archaeologist Thorkild Ramskou posited that the “sunstone” may have been one of many minerals (cordierite or Iceland spar) that polarize gentle and by which the azimuth of the solar may be decided in a partly overcast sky or when the solar is just under the horizon.[1][18] The precept is utilized by many animals;[19] and polar flights utilized the thought earlier than extra superior methods turned accessible.[20][21] Ramskou additional conjectured that Iceland spar may have aided navigation within the open sea within the Viking interval. This concept has grow to be highly regarded,[22] and analysis as to how a “sunstone” could possibly be utilized in nautical navigation continues,[23] typically within the context of the Uunartoq disc.
Analysis in 2011 by Ropars et al.,[24] confirms that one can determine the course of the solar to inside a number of levels in each cloudy and twilight situations utilizing Iceland spar and the bare eye. The method entails transferring the stone throughout the visible subject to disclose a yellow entoptic sample on the fovea of the attention. Alternatively, a dot may be positioned on prime of the crystal in order that if you take a look at it from under, two dots seem, as a result of the sunshine is “depolarised” and fractured alongside totally different axes. The crystal can then be rotated till the 2 factors have the identical luminosity. The angle of the highest face now provides the course of the solar. Makes an attempt to copy this work in each Scotland and off the coast of Turkey by science journalist Matt Kaplan and mineralogists on the British Geological Survey in 2014 failed. Kaplan communicated with Ropars, and neither may perceive why the samples of Iceland spar that had been getting used in the course of the trials didn’t reveal the solar’s course, with the creator hypothesizing that the stones require some expertise to be dealt with successfully.[25]
The restoration of a bit of Iceland spar from an Elizabethan ship that sank close to Alderney in 1592 suggests the chance that this navigational know-how might have endured after the invention of the magnetic compass.[26] Though the stone was discovered close to a navigational instrument, its use stays unsure.[27]
Past nautical navigation, a polarizing crystal would have been helpful as a sundial, particularly at excessive latitudes with prolonged hours of twilight, in mountainous areas, or in partly overcast situations. This might have required the polarizing crystal for use at the side of recognized landmarks. Church buildings and monasteries would have valued such an object as an help to maintain monitor of the canonical hours.[10]
A Hungarian workforce proposed {that a} solar compass artifact with crystals may also have allowed Vikings to information their boats at evening. A kind of crystal they known as sunstone can use scattered daylight from under the horizon as a information. What they recommend is that Iceland spar crystals had been utilized in mixture with Haidinger’s brush. If that’s the case, Vikings may have used them within the northern latitudes the place it by no means turns into fully darkish in summer season.[28] In areas of confused magnetic deviation (such because the Labrador coast), a sunstone may have been a extra dependable information than a magnetic compass.
See additionally[edit]
References[edit]
- ^ a b Ramskou, Thorkild (1967). “Solstenen”. Skalk (in Danish). 2: 16–17.
- ^ Satter, Raphael (March 8, 2013). “Researchers: We may have found a fabled sunstone”. Yahoo! News. Associated Press.
- ^ Turville-Petre, Joan E. (Trans.) (1947). “The story of Rauð and his sons. Payne Memorial Collection II. Viking Society for Northern Research. ISBN 0-404-60014-X.
- ^ a b Faulkes, Anthony. 1966. “Rauðúlfs þáttr: A examine”. Studia Islandica 25. Heimspekideild Háskóla Íslands og Bókaútgáfa Menningarsjóðs. Reykjavík. ISSN 0258-3828. 92 pp.
- ^ Pattern, Ian.”Crystals may have aided Viking sailors“. Guardian (Manchester, UK) p. 8. 7 February 2007. Retrieved December 27, 2010. “Assessments aboard a analysis vessel within the Arctic ocean discovered that sure crystals can be utilized to disclose the place of the solar, a trick that might have allowed early explorers to determine their place and navigate, even when the sky was obscured by cloud or fog.“
- ^ a b Helgadóttir, Guðrún P (ed.). 1987. Hrafns Saga Sveinbjarnarsonar. Oxford: Clarendon Press. ISBN 0-19-811162-2. 267 pp.
- ^ Karlsson, Stefán (ed.).1983. Guðmundar sögur biskups I: Ævi Guðmundar biskups, Guðmundar saga A. Editiones Arnamagnæanæ, Collection B (6). København: C.A. Reitzels Forlag. ISBN 87-7421-387-3. 262 pp.
- ^ Johnsen, Oscar Albert and Jón Helgason (eds.). 1941. Saga Óláfs konungs hins helga. Den retailer saga om Olav den hellige. Efter pergamenthandskrift i Kungliga Biblioteket i Stockholm nr. 2 quarto med varianter fra andre handskrifter. (“Saga of King Olaf the Holy. The good saga of Olav the Holy. After the parchment manuscript no. 2 quarto within the Royal Library in Stockholm with variants from different manuscripts.”) Oslo: Norsk Historisk Kjeldeskrifts-Institutt, Vol. II. pp. 670–1
- ^ Vilhjalmsson, Thorsteinn. 1997. “Time and Travel in Old Norse Society“. Disputatio, (II): 89–114.
- ^ a b c d Einarsson, Árni. 2010. Sólarsteinninn: tæki eða tákn. (Abstract in English: Sunstone: reality or fiction). Gripla 21 (1) 281–97 Árni Magnússon Institute. ISSN 1018-5011.
- ^ a b Einarsson, Árni. 1997. “Saint Olaf’s dream home. A medieval cosmological allegory“. Skáldskaparmál 4: 179–209, Reykjavík: Stafaholt. ISSN 1026-213X
- ^ Einarsson, Árni. 2001. The symbolic imagery of Hildegard of Bingen as a key to the allegorical Raudulfs thattr in Iceland. Erudiri Sapientia, Studien zum Mittelalter und zu seiner Rezeptionsgeschichte (Research on the Center Ages and their reception historical past); II: 377–400. ISSN 1615-441X
- ^ Loescher, G. 1981. “Rauðúlfs þáttr”. Zeitschrift für deutsches Altertum und deutsche Literatur (ZfDA) 110: 253-266. ISSN 0044-2518
- ^ Bragason, Úlfar 1988. “The construction and that means of Hrafns saga Sveinbjarnarsonar”. Scandinavian Studies 60: 267–292. ISSN 0036-5637
- ^ Breeze, Andrew. 1999. “The Blessed Virgin and the Sunbeam Through Glass“. Celtica 23: 19–29. ISSN 0069-1399
- ^ Schnall, Uwe. 1975. Navigation der Wikinger. Nautische Probleme der Wikingerzeit im Spiegel der schriftlichen Quellen. Schr. Deutsch. Schiffahrtsmus. (“Navigation of the Vikings: Nautical Issues of the Viking Age within the Mild of the Written Sources. Writings of the German Maritime Museum“). Band 6. Oldenburg and Hamburg: Stalling, p. 196. ISBN 3-7979-1871-2.
- ^ Ramskou, Thorkild. 1969. Solstenen – Primitiv Navigation i Norden för Kompasset. Köbenhavn: Rhodos. 95 pp.
- ^ Gábor Horváth; Dezsö Varjú (12 January 2004). Polarized Light in Animal Vision: Polarization Patterns in Nature. Springer. p. 447. ISBN 978-3-540-40457-6.
- ^ Moody, Alton B. 1950. “The Pfund Sky Compass”; (by way of page archive at WebCite (archived December 28, 2010)). Navigation. 2 (7): 234–239. ISSN 0028-1522.
- ^ Rogers, Francis M. 1971. “Precision Astrolabe Portuguese Navigators and Transoceanic Navigation – Kollsmann Sky Compass”. Academia Internacional da Cultura Portugeusa (Lisbon, Portugal) pp. 288-291. Retrieved December 29, 2010.
- ^ Hegedüs, Ramón, Åkesson, Susanne; Wehner, Rüdiger and Horváth, Gábor. 2007. “May Vikings have navigated underneath foggy and cloudy situations by skylight polarization? On the atmospheric optical conditions of polarimetric Viking navigation underneath foggy and cloudy skies”. Proc. R. Soc. A 463 (2080): 1081–1095. doi:10.1098/rspa.2007.1811. ISSN 0962-8452.
- ^ Horvàth, G. et al. (2011). ‘On the path of Vikings with polarized skylight: experimental examine of the atmospheric optical conditions permitting polarimetric navigation by Viking seafarers’ Phil. Trans. R. Soc. B (2011) 366, 772–782 doi:10.1098/rstb.2010.0194
- ^ Ropars, G. et al., 2011. A depolarizer as a attainable exact sunstone for Viking navigation by polarized skylight. Proceedings of the Royal Society A: Mathematical, Bodily and Engineering Science. Out there at: http://rspa.royalsocietypublishing.org/content/early/2011/10/28/rspa.2011.0369.abstract Accessed December 5, 2011.doi:10.1098/rspa.2011.0369
- ^ Kaplan, Matt (2015-10-27). Science of the magical : from the Holy Grail to like potions to superpowers (First Scribner hardcover ed.). New York. ISBN 9781476777108. OCLC 904813040.
- ^ “Shipwreck may contain near-mythical Viking navigation aid”. The Raw Story. Agence France-Presse. March 5, 2013.
- ^ “Researchers may have found a Viking sunstone”. CBS News. March 8, 2013.
- ^ Bernáth, Balázs; Farkas, Alexandra; Száz, Dénes; Blahó, Miklós; Egri, Ádám; Barta, András; Åkesson, Susanne; Horváth, Gábor (26 March 2014). “How could the Viking Sun compass be used with sunstones before and after sunset? Twilight board as a new interpretation of the Uunartoq artefact fragment”. Proceedings of the Royal Society A. 470 (2166 20130787): 20130787. Bibcode:2014RSPSA.47030787B. doi:10.1098/rspa.2013.0787. PMC 4042717. PMID 24910520.
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