"Heliometer" Quotes from Famous Books
 ... which Struve chiefly employed it), and for such subtle measurements as might serve to reveal or disprove the existence of a sensible stellar parallax. Fraunhofer, moreover, constructed for the observatory at Koenigsberg the first really available heliometer. The principle of this instrument (termed with more propriety a "divided object-glass micrometer") is the separation, by a strictly measurable amount, of two distinct images of the same object. If a double star, for instance, be under examination, ...
— A Popular History of Astronomy During the Nineteenth Century - Fourth Edition • Agnes M. (Agnes Mary) Clerke |
