parallel rulers

American  

plural noun

1. a pair of straightedges connected by two pivoted crosspieces of equal length so as to be parallel at all times, used for various navigational purposes, especially for transferring the bearing of a plotted course to a compass rose.

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Etymology

Origin of parallel rulers

First recorded in 1695–1705

Example Sentences

See Examples For:

parallel rulers

But he always remembered Elizabeth Boardman and the parallel rulers.

From "Carry On, Mr. Bowditch" by Jean Lee Latham

Now place the parallel rulers along that line and slide them over until the nearest edge intersects the center of the compass rose at the bottom or side of the chart.

From Lectures in Navigation by Draper, Ernest Gallaudet

Then with the parallel rulers carry the bearing of one object from the chart compass card until you can intersect the object itself and draw a line through it.

From Lectures in Navigation by Draper, Ernest Gallaudet

Writing; materials for writing; pens; inks; use of coloured inks for denoting numbers; polygraph; telegraph; geometrical instruments; rulers; compasses; flexible rulers; squares; triangular compasses; parallel rulers; Marquois's scales; pantograph; proportional compasses; sector.

From Heroes of Science: Physicists by Garnett, William

He entered the cabin that had been used as a chart room and rummaged the desk for parallel rulers and dividers; but a soft step behind him brought him to a stand quickly.

From Gold Out of Celebes by Dingle, Aylward Edward