BBQ woes

It started out cold and foggy, but by lunchtime the sun was out.  Just as well because we went to the sister-in-law's on the promise of a barbecue.  I was cooking of course.  Strange BBQ, well strange to me. It is a Weber so a very solid machine.  But I couldn't get the gas to come through.  I took off the slightly strange regulator and put it back on a few times, nothing.  I changed to a different cylinder, nothing.  I poked about underneath to see if there was a second on/off valve, there wasn't.  We tried matches but still nothing, no gas.  We were about to give up and I am certain that I heard the sausages snigger a few times.  Finally, I took the regulator off again for a more thorough inspection.  It clicked on and off okay, the button pushed in and out okay and then, under no particular instruction from me, it seemed to turn clockwise. Idiot, idiot, idiot me, you had to turn it 180 degrees clockwise after you locked it onto the gas bottle and clicked the on button.  Sausage sniggers soon turned to sausage sizzles (that'll teach them) and corn and burgers were soon on their way.