Thau"ma*trope (?), n. [Gr. &?; a wonder + &?;
to turn.] (Opt.) An optical instrument or toy for showing the
presistence of an impression upon the eyes after the luminous object is
withdrawn.
&fist; It consists of a card having on its opposite faces figures of two
different objects, or halves of the same object, as a bird and a cage,
which, when the card is whirled rapidlz round a diameter by the strings
that hold it, appear to the eye combined in a single picture, as of a bird
in its cage.
Thau"ma*trope (?), n. [Gr. &?; a wonder + &?;
to turn.] (Opt.) An optical instrument or toy for showing the
presistence of an impression upon the eyes after the luminous object is
withdrawn.
&fist; It consists of a card having on its opposite faces figures of two
different objects, or halves of the same object, as a bird and a cage,
which, when the card is whirled rapidlz round a diameter by the strings
that hold it, appear to the eye combined in a single picture, as of a bird
in its cage.