Nautical Solid Brass Sextant With Two Extra Sighting Telescope

The Nautical Sextant - W. J. Morris, PDF

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直売直送 【輸入品・未使用】Solid Brass Sextant With Two Extra Sighting Telescope-Marine Gift-Astrolabe - その他

Surveyors Box - Singapore

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Solid Brass Sextant With Two Extra Sighting Telescope Marine Gift

Obviously this is a compass. But what is the arc on the side for

Nautical Solid Brass Sextant With Two Extra Sighting Telescope Marine Gift Astrolabe

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