Chicago Tribune, October 13, 1919, page 3:

    What was declared one of the greatest feats of electrical science was demonstrated yesterday at the electrical show in the Coliseum. A tune whistled into a wireless telephone by an operator there was heard clearly by other operators in Ludington, Mich., and Milwaukee. The stations at these two cities have apparatus capable of receiving messages but are not able to send.
    The operator at the Coliseum talked to the two stations during the entire afternoon and answered his questions by wireless telegraphy, advising him whether or not they were hearing him clearly.
    At the radio station in the Transportation building Lieut. Wells also talked to Capt C. C. O'Leary at the Coliseum.
    The demonstrations are being conducted in conjunction with a recruiting campaign for the signal corps. An army plane is being made ready to make flights with a wireless phone set and beginning Tuesday visitors at the show will hear talks from an airplane.
    A number of features are being arranged by E. W. Lloyd, manager of the exposition for Electric Club day tomorrow. Members of the Electric club will meet in the Coliseum ballroom for a luncheon. They will be addressed by Samuel Insull, W. D'Arcy Ryan, and others prominent in the electrical world.