axis

The Sailor's Word-Book

The imaginary line upon which a planet revolves, the extremities of which are termed the poles, therefore a line joining the north and south poles. The real or imaginary line that passes through the centre of any cylindrical or spherical body on which it may revolve. Also a right line proceeding from the vertex of a cone to the middle of its base. Also, an imaginary right line passing through the middle of a ship perpendicularly to its base, and equally distant from its sides; an imaginary line passing through the centre of a gun's bore, parallel with its position.


♦ Axis of a telescope. (See collimation, line of.)

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