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 3/11/2017 Nico Mozzer discovered it   Visit Log

Dirk, dikke merci dat ik deze mag discoveren ! Knappe collectie ! Ik zal die van mij er eigenlijk ook eens moeten inzetten ! Greetz Nico Mozzer !
Discovered It 3/11/2017 zappalodian discovered it   Visit Log

Woow wat een collectie. Bedankt om die te mogen ontdekken.
Discovered It 3/5/2017 idabruno discovered it   Visit Log

Bedankt om deze te delen.
Groetjes Ida
Discovered It 3/4/2017 Lady Linneke discovered it   Visit Log

Merci voor deze te mogen discoveren. Grtjes Linda
Discovered It 3/4/2017 Cynphil discovered it   Visit Log

Deze gespot tijdens één van onze geocache-uitstapjes.
Bedankt om deze te delen !
Met vriendelijke groeten, Survival71.
Discovered It 1/13/2017 LordT discovered it   Visit Log

Gespot in JL's Treasure Chest. Indrukwekkende en mooie collectie!
Discovered It 12/26/2016 Jule242 discovered it   Visit Log

Danke fürs zeigen sagt Jule242
Discovered It 9/5/2016 Keeef20 discovered it   Visit Log

Dich haben wir gesehen :-)
Danke fürs zeigen sagen Keeef20 :-)
Discovered It 8/1/2016 Spasskaiser discovered it   Visit Log

Nach langer Zeit des "Sammelns" von Geocoin- und Trackablecodes, vor allem auf events, habe ich heute endlich mal die Ruhe und Muße, mich an´s Discovern zu machen.

Danke für´s Zeigen und Grüße aus Köln!
Discovered It 6/27/2016 sparadrap + tibecom discovered it   Visit Log

Deze TB kunnen logen bij een recente ontmoeting met J Lightning himself
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