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The mariner's astrolabe is a simplified version of the instrument used by astronomers. This iteration of the astronomical device was adapted for use at sea, and was employed by Portuguese sailors no later than 1481.

The precise date of the discovery of the magnetic needle compass is undetermined, but the earliest attestation of the device for navigation was in the Dream Pool Essays by Shen Kuo (1088).

The earliest iterations of the compass consisted of a floating, magnetized lodestone needle that spun around in a water filled bowl until it reached alignment with Earth's magnetic poles.

The Junk ship design popularized by the Chinese was both innovative and adaptable. The size of these ships could vary considerably, with the largest ships purportedly reaching 450 ft. length and 180 ft. width, according to 16th century writer Luo Maodeng.

Junk vessels employed mat and batten style sails that could be raised and lowered in segments, as well varying angles.

The Eastern Roman Empire controlled the sea lanes, ports, and overland trade routes in the Eastern Mediterranean region following the disintegration of unified Roman rule and the emergence of the earliest Islamic caliphate.