Cross Staff & Back Staff Geocoin

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Owner:
johnny lightning Send Message to Owner Message this owner
Released:
Wednesday, October 3, 2012
Origin:
Antwerpen, Belgium
Recently Spotted:
In the hands of the owner.

This is collectible.

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Current Goal

Stay in JL's Treasure Chest

About This Item

copper

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

Discovered It 5/16/2015 THE_Chris discovered it   Visit Log

Discovered at some point during the Giga/Maze weekend in Mainz. Thanks for sharing, no matter how you did it!

Total Tally: 4,277 bugs and coins including:
3,475 from peoples collections via scanned QR codes.
105 trackable people & log stamps [written down by hand and painstakingly transcribed]
697 photographed either on collection sheets or directly. Painstakingly transcribed as well!
Discovered It 5/16/2015 Michigirlandfamily discovered it   Visit Log

Auf dem GIGA IN MAINZ GESEHEN.

Discovered It 5/16/2015 Strahlenspecht discovered it   Visit Log

in Mainz beim GIGA.
Discovered It 5/16/2015 Strahlenspecht discovered it   Visit Log

in Mainz beim GIGA.
Discovered It 5/16/2015 Strahlenspecht discovered it   Visit Log

in Mainz beim GIGA.
Discovered It 5/16/2015 Trebbi discovered it   Visit Log

Diesen TB/Coin konnte ich mit vielen anderen auf dem Giga in Mainz sehen... auf einem T-Shirt, auf einer Mütze, in einem Stempel, auf einer Liste, auf dem Rucksack, als Coin im Coin Raum, an einem Hund... oder sonst irgendwo!
Danke fürs zeigen ;)
Discovered It 5/16/2015 Strahlenspecht discovered it   Visit Log

in Mainz beim GIGA.
Discovered It 5/16/2015 -ShadowHunter- discovered it   Visit Log

Discovered it. Thank you for sharing.
Discovered It 5/16/2015 Bonjoel01 discovered it   Visit Log

Seen at the Giga event in Mainz
Discovered It 5/16/2015 frankenlady discovered it   Visit Log

Beim Giga gab´s viel zu entdecken, vielen Dank dafür!
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