| 释义 |
dipleidoscope|dɪˈplaɪdəskəʊp|
[f. Gr. διπλό-ος double + εἶδος form, image + -σκοπος viewing, a watcher.]
An instrument consisting of a hollow triangular prism, with two sides silvered and one of glass, used for determining the meridian transit of a heavenly body by the coincidence of the two images formed by single and double reflexion.
1843E. J. Dent (title), A Description of the Dipleidoscope. Ibid. (1867) 14 The criterion for determining the position of the Dipleidoscope is, that the two images must coincide, or appear as one, when the chronometer shows, according to the equation table for 1868, 11h. 49m. 12.1s. 1851Offic. Catal. Exhib. I. 414. 1884 F. J. Britten Watch & Clockm. 88 The advantages of the dipleidoscope over the ordinary forms of sun dials are: the passage of the sun over the meridian is indicated with greater exactness, and the reflections may be discerned in weather too cloudy to see any shadow on the sun dial. |