spherograph

spherograph is defined in Webster's Unabridged Dictionary (1913) with 1 sense. The full text of each entry is reproduced verbatim below.

Definitions

  1. 1.An instrument for facilitating the practical use of spherics in navigation and astronomy, being constructed of two cardboards containing various circles, and turning upon each other in such a manner that any possible spherical triangle may be readily found, and the measures of the parts read off by inspection.

Source: Webster's Unabridged Dictionary, 1913 edition (public domain, via GCIDE / Project Gutenberg).

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