Cross Staff & Back Staff Geocoin
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Owner:
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johnny lightning
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Released:
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Wednesday, October 3, 2012
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Origin:
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Antwerpen, Belgium
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Recently Spotted:
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In the hands of the owner.
This is collectible.
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Antique Copper version
A very early navigational instrument, the cross staff was widely used among surveyors and astronomers. It was not until the 1500s, after it was developed further, that it started to be used at sea.
The name is derived from its cross shape. It was cumbersome to use simply because a user had to focus on the horizon and star or sun at the same time; moving your eyes from one to the other and at the same time sliding the transversal (cross piece) until you achieved what you thought would be an accurate reading. It also required looking straight into the sun when taking daytime readings. It was with the invention of the back staff that these problems would be resolved.
John Davis invented a back staff in 1595 and his improved design became known as the Davis Quadrant. It rendered the cross staff obsolete since the user only had to take a sight at one object and didn't have to look at the sun to take a reading. Appropriately named, its basic design is like a cross staff, but with some enhancements, and daylight readings were taken by having your back towards the sun. In many cases, John Davis's invention ended up replacing not only the cross staff, but also the mariner's astrolabe and quadrant. It was in the late 1700s when the octant and sextant became the new preferred tools over the back staff.
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Tracking History () View Map
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Ermsritter discovered it
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Auf dem Giga in Mainz entdeckt und discovern dürfen. Vielen Dank für´s Zeigen.
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MaZoNe discovered it
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Urlaub, endlich. Gleich am ersten Tag werden die Handybilder der TB's bereinigt um Platz für Neue zu machen. Vielen Dank für die Möglichkeit, sie discoern zu dürfen, auch, wenn es zum Teil schon recht lange her sein kann, dass ich sie fotografiert habe.
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acubee discovered it
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Discovered it. Thank you for sharing.
danke fürs zeigen. viele grüße acubee
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nigg_ae discovered it
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Diese aussergewönliche Geocoin/Trackable am Gutenberg-Giga-Event in Mainz gesehen.👍
Vielen Dank für's Zeigen.
Grüsse aus der Schweiz, niggae.
This nice Geocoin/Trackable seen on the Gutenberg-Giga-Event Mainz 👍.
Thanks for sharing!
Greetings from Switzerland, niggae.
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buisset discovered it
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bedankt om te mogen discoveren. grts, hilde.
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DAS-Gruppe discovered it
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Während des GIGA-Events Mainz Gutenberg 2015 habe ich eine Menge Coins und TB's zum Discovern gefunden.
Unter allen tollen Einzelstücken und Listen waren viele schöne Dinge dabei und dafür bedanke ich mich. Sollte dieser TB oder diese Coin nicht zum discovern gedacht sein, dann bitte einfach diesen Logeintrag löschen. Bei allen stolzen Besitzern bedanke ich mich fürs Zeigen und Discovernlassen.
Danke für's Discoverndürfen
Thanks for sharing
Peut discovern Merci pour
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Werner91 discovered it
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swasti discovered it
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danke fürs zeigen. wo auch immer (cache,event,groundspeak gallery, facebook, ...)
wünsche deinen coins/tbs weiterhin eine gute reise!
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Team Yellow LM discovered it
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Beim GIGA-Event in Mainz haben wir viele Coins & TB´s gesehen und discovered.
Danke fürs zeigen.
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AR-Team discovered it
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GIGA Mainz - The Gutenberg GIGA.
seen this trackable and discover it now.
Great Journey and have a save trip on your mission
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