Cipher printing telegraph systems

L. F. Morehouses This work on the development of arrangements for secretly transmitting telegrams was done during the War under the direction of Mr. Gherardi. The problem was to see if a simple and effective means that would be entirely secret could be devised for handling telegraph business. The method used should be such that an enemy could not decipher the messages even if he could capture the mechanism used, thoroughly understand its operation, and obtain contact with the line circuits.