in-house, hands-free telephone system using microphones and loudspeakers, patented 1907 in U.S. by K.M. Turner and W. Donnan, from dictation + -graph in the sense of "instrument for recording."
Entries linking to dictograph
dictation n.
1650s, "authoritative utterance," from Late Latin dictationem (nominative dictatio) "a dictating, dictation," noun of action from past-participle stem of dictare "say often, prescribe," frequentative of dicere "to say, speak" (from PIE root *deik- "to show," also "pronounce solemnly"). Meaning "act or practice of expressing orally for another to write down" is by 1727.
-graph
modern word-forming element meaning "instrument for recording; that which writes, marks, or describes; something written," from Greek -graphos "-writing, -writer" (as in autographos "written with one's own hand"), from graphe "writing, the art of writing, a writing," from graphein "to write, express by written characters," earlier "to draw, represent by lines drawn" (see -graphy). Adopted widely (Dutch -graaf, German -graph, French -graphe, Spanish -grafo). Related: -grapher; -graphic; -graphical.