sentences:  The rationale behind this device was that saccades are easier to perceive and register aurally than visually.In 1889, Edmund B. Delabarre invented a system of recording eye movement directly onto a rotating drum by means of a stylus with a direct mechanical connection to the cornea.Other devices involving physical contact with the surface of the eyes were developed and used from the end of the 19th century until the late 1920s; these included such items as rubber balloons and eye caps.