Peter Brueggeman is right, I wasn't really thinking of the touring derailleurs of the 30's. From a quick dip into Berto...in addition to Albert Raimond's Rosa there was also the 'Le chat' (1931)and prior to that the 'Integral' which had in effect a double seat tube with the chainrings between and had a cable operated front derailleur way back in 1928. There must have been some for conventional frames earlier than the Rosa. The thing I find interesting is that front clanger, rod or suicide derailleurs stayed in use on racing bikes for so long. Why was that? Surely their weight was greater and the cost of the Simplex and Huret gears wasn't so great. was it their reliability or racers' conservatism? I'll have to give Berto another read...