What is "reflecting goniometer"

Goniometer \Go`ni*om"e*ter\, n. [Gr. ? angle + -meter: cf. F. goniom[`e]tre.] An instrument for measuring angles, especially the angles of crystals, or the inclination of planes.

Contact goniometer, or 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.

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.

Reflecting \Re*flect"ing\, a.

1. Throwing back light, heat, etc., as a mirror or other surface.

2. Given to reflection or serious consideration; reflective; contemplative; as, a reflecting mind.

   Reflecting circle, an astronomical instrument for measuring angless, like the sextant or Hadley's quadrant, by the reflection of light from two plane mirrors which it carries, and differing from the sextant chiefly in having an entire circle.

   Reflecting galvanometer, a galvanometer in which the deflections of the needle are read by means of a mirror attached to it, which reflects a ray of light or the image of a scale; -- called also mirror galvanometer.

   Reflecting goniometer. See under Goniometer.

   Reflecting telescope. See under Telescope.