Thanks a lot, Woodinsight !
It looks absolutely fantastic. Does it covers only the "new" cars of the day, or does it goes back to the very beginning, Benz Patent Motorwagen and all ?
Well I have to say that the majority of the coverage is of cars that were new at the time although there is mention/photos of older cars in some cases.
However there are a few pages devoted to the history of the motor car and there is a technical illustration of an 1897 Benz (see below).
There was also a weekly publication in 164 parts (with binders) that covered the history of the motor car named "On Four Wheels".
This was published in the 1970s by Orbis and also included photos and diagrams of many older cars and technical features.
You can try to find a bound set of those in 11 volumes although I don't know current prices.