the battery circuit so that when the electric waves acted on the coherer the signals would be printed on a tape in dots and dashes.
In his first attempts, then, to send wireless messages, young Marconi had done four things and these were (1) to see the possibilities of using electric waves set up by a Hertz apparatus for sending messages; (2) to put a telegraph key in the sending circuit; (3) to use a Popoff receiver for receiving the electric waves, and (4) to put a Morse register in the receiving circuit. These were the first big steps in building up a wireless telegraph set, but none of them formed an invention.
I do not know just when Marconi added the aerial and ground to his transmitter—Popoff had used an aerial and ground with his receiver—but the aerial and ground formed his great claim to being the inventor of the wireless telegraph, for it was the aerial and ground which enabled him to cover long distances.
In 1896 Marconi went to England and there applied for a patent in which he showed an aerial and ground connected to his sending and receiving apparatus (see the diagram) but even at this time he did not understand the impor-