The Nautical Encyclopedia

Patterson’s Illustrated Nautical Encyclopedia — Howard Patterson, 1891

⚓ The Superstition Locker ⚓

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Home ⚓ Letter S ⚓ Semi-diameter

Semi-diameter

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Half a diameter; the radius of a circle.

Parallax and semi-diameter

← Semicircular Deviation All “S” entries Semi-diurnal Arc →

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