Sending telegrams. Coloured historical artwork of a telegraph office in London, England. The operator at lower right is tapping out a message on an electric transmitter. The operator at lower left is receiving a message that is being imprinted onto a paper strip. Electric telegraphy developed in the mid-19th century. Information was transmitted by wire or radio waves, using a set of coded signals such as the Morse code. Early receivers employed a stylus controlled by an electromagnet. The stylus imprinted code onto a strip of paper in response to the signal being transmitted. Taken from The Graphic, 1871.