Spherograph
Pronunciation : Spher"o*graph
Part of Speech : n.
Etymology : [Sphere + -graph.]
Definition : Defn: 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
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