The Nautical Encyclopedia

Patterson’s Illustrated Nautical Encyclopedia — Howard Patterson, 1891

⚓ The Superstition Locker ⚓

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Home ⚓ Letter S ⚓ Secondary Circle

Secondary Circle

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A great circle of the sphere which passes through the poles of another.

← Secondary All “S” entries Secondary Meridians →

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The Nautical Encyclopedia (1891) is in the public domain; this digital edition © 2026 PhotoOpAI.