A mull is a promontory. Mull can also mean to ponder or consider. Mulling wine, beer or cider is heating it with sugar and spices. Eg I went to the Mull of Kintyre and mulled over whether or not to have a glass of mulled wine.
Mull apparently can also be a form of non acidic compost or a particular type of muslim, so I suppose I could have sat on a pile of mull at a mull* in the company of a mull. We may have mulled things over together, but we’d not have drunk any mulled wine.
*Not Kintyre though as the soils is acidic there.
Now I could have mulled some wine and photographed that as I do like the stuff, but instead here’s one of the foghorn at the Mull of Galloway. (I don’t actually know the man in the picture, but he stayed there so long I took the shot anyway, then walked down to see what he was looking at. It was a HUGE seal. He (the man, not the seal) then pointed out various different birds and explained about the tides and other interesting stuff.)