Sorry Manfred - it's the "fahrt" (which I know has several meanings in German, in this case "walk"). My feeble attempt at humour was based on the similarity to the English word "fart". I don't know how that translates into German - if you need a translation, I'm sure someone here can provide one. A translation, I mean. :-)

I suspect though, that my "joke" might have turned out to be true - "many a true word is spoken in jest", as we say here (sometimes!)