"You've got one admirer," she said to Tietjens. "'Punched that rotten strap,' he goes on saying, 'like a gret ol' yaffle punchin; a 'ollow log!' He had a pint of beer and said it between each gasp." She continued to narrate the quaintnesses of Joel which appealed to her; informed Tietjens that "yaffle" was Kentish for great green woodpecker ... [119-20]Some of us, raised on this later masterpiece, wouldn't have needed telling. I don't think I realised how specifically Kentish Bagpuss was, although of course Postgate was a Man of Kent (I met him, when I was a teenager making films at school in Canterbury and he made a barn on his property available to us; he was thoroughly courteous). When UKC gave him an honourary degree he apparently declared that it was really for Bagpuss; but I prefer to think of it as the official acknowledgement of the academic standing of Professor Yaffle, full name "Augustus Barclay Yaffle".
My theory is that Bagpuss himself has aristocratic antecedents: he may be distantly related to Ralph-de-Bagpuis, a French nobleman who assisted William the Conqueror in his invasion of England in 1066 (the Oxfordshire village Kingston Bagpuize is, Wikipedia informs us, named after him).