goniometer : Idioms & Phrases


Contact, ∨ Hand, goniometer

  • a goniometer having two movable arms (ab, cd), between which (at ab) the faces of the crystals are placed. These arms turn about a fixed point, which is the center of the graduated circle or semicircle upon which the angle is read off.
Webster 1913

Reflecting goniometer

  • an instrument for measuring the angles of crystals by determining through what angular space the crystal must be turned so that two rays reflected from two surfaces successively shall have the same direction; called also Wollaston's goniometer, from the inventor.
Webster 1913