Telegraph Domestic vs. International Traffic

      This series of maps is related to the ones shown in Series 1. It depicts the development of domestic telegraphy versus international telegraph traffic from 1870 to 1930. The key indicator is again the number of telegrams wired through cables in specific countries, and in this series domestic and international proportions of this traffic are placed into a split pie-chart diagram. A constant scale has been used. Thus, these maps enable the reader to examine the amount of telegraph traffic by country through time, and to examine up to what degree telegraphy was an international or national matter. As in Series 1, the data presented in this series has been taken from a variety of transnational sources on telegraph communications now contained in the TIE-Database maintained at Eindhoven University of Technology.