A·nor'tho·scope noun [ Greek 'an priv. + ... straight + -scope .] (Physics) An optical toy for producing amusing figures or pictures by means of two revolving disks, on one of which distorted figures are painted. Found on http://www.encyclo.co.uk/webster/A/89
The anorthoscope is an optical apparatus described by Carpenter in 1868. In it distorted figures lose their distortion when in rapid motion. Found on http://www.probertencyclopaedia.com/browse/GA.HTM