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

But he always remembered Elizabeth Boardman and the parallel rulers.

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

Parallel Rulers The parallel rulers need no explanation except for the way in which they are used on a chart.

From Lectures in Navigation by Draper, Ernest Gallaudet

Captain Ponsberry said no more, but threw down his parallel rulers and his pencil.

From At the Fall of Port Arthur Or, A Young American in the Japanese Navy by Stratemeyer, Edward

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

I crossed the Channel on the 29th of July 1863, embarrassed by the possession of two ladders, each twelve feet long, which joined together like those used by firemen, and shut up like parallel rulers.

From The Ascent of the Matterhorn by Whymper, Edward