I have just uploaded an illustration of a rarely seen cable-operated front derailleur from Simplex. This was made from 1952 to 1956. The enlarged scanned image is from "The Dancing Chain". Except for Campagnolo's Gran Sport, most all other front derailleurs of this era were still rod-actuated changers.
Even more exciting to see is a current eBay offering of a beautiful New-Old-Stock example of this model - the first one I've ever seen for sale! The seller located in Vienna, Austria shows four excellent photos on his auction page. (The eBay auction number is referenced in my caption for this image.)
BOB HANSON, ALBUQUERQUE, NEW MEXICO, USA