"Go bring me a mug of your very best ale, Bad ale can drag a man down." "The lord of the castle a bold knight was he, He started to London the Queen for to see." "His cloak it was velvet for a grand lord was he, He rode a white charger...."
Thomas, obscurely, lists this in her section on chanteys. The first verse, I suppose, might be; the second and third appear to be part of an unrelated ballad. But with only two lines of the first and four of the second, I can't identify it.
It may well be mixed up with another song in Thomas, "Abie's White Mule." - RBW