Mariner's Nautical Astrolabe
The word Astrolabe comes from Greek astron, meaning "star" and lambanien, "to take, to look for". It is considered the mathematical jewel of astronomy.
The nautical astrolabe is a simplification of the planispherical or astronomical astrolabe and its fundamental purpose is to obtain one's latitude, by observing the altitude of the sun or other stars as the Pole Star. Adapted for use by mariners aboard sailing ships, the nautical astrolabe is heavier and has holes cut through the plate to make it less susceptible to wind gusts.
The mariner's astrolabe we feature is based on a historical example of one which was discovered off the coast of Valentia island, Ireland, where 3 ships of the Spanish Armada were sunk in 1588.
It is fully functional and made of a durable metal alloy which is lacquered and will not rust. The astrolabe is provided with a wooden display stand and a comprehensive instruction manual which describes its history as well as instructions for use.
Historical Reference: http://collections.rmg.co.uk/collections/objects/42234.html