Cross Staff & Back Staff Geocoin - Antique Silver

Die Cross Staff & Back Staff Geocoin^™ von www.compassrosegeocoin.com ist eines der besonderen Stücke für unsere gemeinsame Sammlung der Fam_RuhrpottDachse (MrsDachs und Dachs71).

Navigation früher und heute ist ein spannendes, lehrreiches und zugleich praktisch anwendbares Thema.

Andere Geocacher dürfen diese Coin gerne anschauen und Discovern.

Icon 2272 - Cross Staff & Back Staff Geocoin - Antique Silver

Die Coins haben einen Durchmesser von 50,8mm und eine Materialstärke von 5mm.

Es gibt die seit 2008 diese Coins in diesen 4 Versionen (bisher 1390 Codes beantragt):

-Antique Bronze

-Antique Copper

-Antique Silver

-Black Nickel (LE)

Navigation früher und heute ist ein spannendes, lehrreiches und zugleich praktisch anwendbares Thema.

Die früheren mechanischen Navigationsinstrumente sind ein interessantes Thema, dass www.compassrosegeocoin.com gut in optisch schöne Geocoins umgesetzt hat. Vielen Dank.

Einen Dank auch an johnny lightning aus Belgien, von dem wir drei Versionen dieser älteren Conis übernehmen und zum Leben erwecken konnten. Danke.

Auf der Homepage zur Coin gibt es eine kleine Erläuterung:

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.

Weitere Informationen zur Cross Staff & Back Staff Geocoin^™ findet man unter:

http://www.compassrosegeocoin.com/crossbackstaff.php

Die Serie umfasst:

• Compass Rose Geocoin^™
• Cosmolabe Geocoin^™
• Cross Staff & Back Staff Geocoin^™
• Mariner's Astrolabe Geocoin^™
• Nocturnal Geocoin^™
• Planisphere Geocoin^™
• Quadrant Geocoin^™
• Sextant Geocoin^™
• Sextant Geopin^™
• Sextant Navigation Geocoin^™
• Universal Ring Dial Geocoin^™