The Wonders of Modern Mechanism, Charles Henry Cochrane, 1896, pages 396-397:
THERE are very many more wonderful mechanisms than can be mentioned within the compass of this book. The ingenuity of mankind continues to prompt to new efforts, and the ideas of one inventor furnish food for another, so that the increase is constantly augmented. A few of these are briefly noted here by way of conclusion.
There exists in Paris a Theatrophone Company, whose name will suggest their business to any student of Greek. Since 1882 they have been connecting their patrons by telephone with the various theatres of the city, and their mechanism has been perfected so as to give a satisfactory service. The first experiment was made in 1881, twenty pairs of transmitters being placed on the stage of an opera-house, on either side of the prompter’s box and in front of the footlights. A battery was connected, and double wires led to a line of receivers. Each receiver connected with a transmitter on the right of the stage and with another on the left of the stage, so that the listener could hear equally well, no matter on which side the action might be taking place. The result was so satisfactory that the above-named company was formed and the system developed. They now have a central office and seven radiating lines of wires, to which are connected hotels, restaurants, and dwellings. A special room is provided for them in each of the theatres, with an attendant to see that all the transmitters are maintained in working order. At the central office are two young women--one to talk to subscribers who may desire to have this theatre or that one connected, and the other to make the connections and watch to see that all the lines are working properly. There are special contrivances for regularly verifying the condition of the lines. Between the acts the Theatrophone Company connects subscribers with music of its own production, so that something is to be heard the whole evening. By these means the company has maintained a reliable service, and secures good prices, varying according to the number of theatres connected. The receiving telephones are arranged for individual use like an ordinary telephone, or with a wide-mouthed funnel to disperse the sound so that several persons can hear at the same time. No doubt the company will shortly, if they have not already, add the kinetoscope in some manner to their service, so as to give a more perfect representation of the performances.