[The "Ring Test" for evaluating eye dominance].

A horizontal diplopia is produced with prisms whose bases are nasal or temporal. The subject has to fixate a circle, now seen double, alternately with his left and right eye and touch the center of the circle with a finger. Of one hundred subjects thus examined, 85 located the circle accurately every time when the one eye was fixating it and always missed when fixating with the other eye. This appears to prove that dominance of one eye also means that it is preferred for binocular spatial orientation.