George Melly Ronnie Scott's, Birmingham
"Well, he can't actually sing or play an instrument...", said a man at a nearby table attempting to explain the discreet charms of Melly to his companion before the show. And, after the tumultuous encore, the shouting and stamping and begging for more, I overheard the following Pinteresque exchange in the gents: "Of course, he's well over 80 now." "Didn't he used to play the trumpet?" "Yes, but that was a very long time ago."

In attempting to probe the mystery of Melly, who is clearly many things to many people, the idea that he is really two things - a dandyish intellectual on the one hand, and a low down and dirty blues singer on the other - has a certain attraction to it. But when you see him in performance there really is a convergence of the twain. The erudite introductions detailing the derivations of classic blues are mixed with blue gags that could derive from Max Miller, while the songs themselves are scholarly glosses on the original versions by Bessie Smith or Ma Rainey. You could even draw one of those mad lists to show that Melly's mix of high art, high camp and low humour goes way back: Bessie Smith was a friend of Carl Van Vechter, who was a friend of Ronald Firbank, who probably knew the camp singer Douglas Bung, who influenced Frankie Howerd...

Melly has more than a bit of all of them and although he's no obvious Jack the Lad, he really does have the common touch. Despite the remains of at least half a plum in his mouth, and the rather abstracted air of the Senior Common Room, he can still come out with a punch-line as coarse as one of Roy "Chubby" Brown's. "Why don't you buy a vase?" for example. It's rather as if you were to stumble upon your old headmaster doing stand- up in a strip-club.

Though he's now 70 and has been doing this sort of show (in fact, exactly this show, some of it word for word) for donkey's years), Melly keeps getting better. True, he does look tired now and then, when he takes a seat for a brief rest, goes out of role and looks out at the crowd rather forlornly, but in the second half he gets another wind - and a change of costume into that venerable old blazer, recalling the actor Dennis Price up to no good - and he just flies. Though his singing has always been, perhaps, that of someone acting singing, it's still a hell of an act, and in "Underneath The Arches" (dedicated to the homeless), and "Our Love Is Here To Stay", he was wonderfully affecting. You really have to seize the chance and see him while he's still at his worst.

George Melly, with John Chilton's Feetwarmers, plays a Christmas season at Ronnie Scott's, London from 15 December to 3 January. Tel: 0171 439 0747.