Electrical Review and Western Electrician, August 21, 1912, page 421:
The Teleprinter.
    Business offices, large hotels and other establishments in Berlin and Hamburg, are now subscribers to the teleprinter exchange. Each office is supplied with one of the new instruments, and anyone can use it to send messages to another subscriber just as he would operate a typewriter. Connection is first made through the central exchange, then all that is needed is to press one of the keys so as to start up. Other keys bear letters and figures, and at the other end a type wheel prints the letters on a paper strip. What is intended is to provide an instrument which any one can use, and without the training which is required by a typewriter. For this reason the keyboard has the letters placed in regular alphabetical order. Messages are received even if the case is locked up, so that no one but the person having the key is able to read them. When it is desired to send a telegram from a business office to the city telegraph office, this can be done by making direct connection with the telegraph office, as each subscriber can have a teleprinter placed there in the special room devoted to this purpose. Messages are thus sent and received directly and without any loss of time. Up to date there are over 1,200 of the instruments in use in Germany.