The original separations were sent from Chicago to New York in 1924 by Dr. Herbert E. Ives of the Bell Telephone Laboratories. The separations were made by Max Hofsetter of Powers Photo Engraving of New York. Powers made a three color reproduction using the lines created by the transmission process to create the halftone screening.
Rotating each of the three separations as it was mounted on the transmitter enabled the colors to be screened by the transmission process at the appropriate angle relative to one another.
To watch a video showing how photographs used to be sent by wire, clink on the link HERE