By Lluís Len and Jaume Perarnau. Published by MNACTEC and Rafael Dalmau, 2004.
This book, overseen and coordinated by the MNACTEC, is a landmark work on Catalan optical telegraphy. It deals with the background and beginnings of optical telegraphy, and the arrival in Catalonia of electrical telegraphy. It includes more than 108 optical telegraphy pylons.
