Ac-tĭn'o-grāph, n.
n. [Gr. ἀκτίς, ray, and γράφειν, to describe.] (Opt.) An instrument for measuring and recording the variations in the actinic or chemical force of the solar rays. Nichol.
n. [Gr. ἀκτίς, ray, and γράφειν, to describe.] (Opt.) An instrument for measuring and recording the variations in the actinic or chemical force of the solar rays. Nichol.