Source: “das Motorrad” nr. 26/1970.
I hope somebody shows up with drawings and/or more facts about this machine from 1909 and its creator!
[14-03-2006] According to Sebastien Faures, a Vintage car specialist from France, the so-called Zedel system has been in fact initiated by Giovanni Enrico at Fiat in 1905.
For the spring controlled Fiat version, see last pic.