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The four basic instruments for navigation: Sinan, Inch Astrolabe, Sextant and nautical map Sinan, the ancient Chinese compass
The four basic instruments for navigation: Sinan, Inch Astrolabe, Sextant and nautical map. Sinan, the ancient Chinese compass
It was invented by Zhang Heng in the Han dynasty. It is made up of a bronze foundation(青铜地盘)and magnetic spoon(磁勺) which is made of natural magnet, positioned right in the central of the foundation
It was invented by Zhang Heng in the Han dynasty. It is made up of a bronze foundation (青铜地盘) and magnetic spoon(磁勺) which is made of natural magnet, positioned right in the central of the foundation
The handle of the spoon points to the south, while the other side points to the north. When the sinan is in the still, the handle of the spoon points to the south because of influence of the terrestrial magnetism(地磁)
The handle of the spoon points to the south, while the other side points to the north. When the Sinan is in the still, the handle of the spoon points to the south because of influence of the terrestrial magnetism (地磁)
It has 1/ stars listed as well as a map of the sky overhead (for 37 degrees)and the ecliptic(黄道. The time of day or night is on the outside astrolabe edge with noon at the top of the astrolabe and midnight at the bottom It comes with a carrying chain, a pouch, and a book on its use. The reverse side has a sight for measuring the elevations of the heavenly bodies
It has 17 stars listed as well as a map of the sky overhead (for 37 degrees) and the ecliptic (黄道). The time of day or night is on the outside edge with noon at the top of the Astrolabe and midnight at the bottom. It comes with a carrying chain, a pouch, and a book on its use. The reverse side has a sight for measuring the elevations of the heavenly bodies. astrolabe