My eyes were yet wandering, from young Mr. Turveydrop working so hard, to old Mr. Turveydrop deporting himself so beautifully, when the latter came ambling up to me and entered into conversation.
This little apostrophe to Mrs. Smallweed is occasioned by a propensity on the part of that unlucky old lady whenever she finds herself on her feet to amble about and "set" to inanimate objects, accompanying herself with a chattering noise, as in a witch dance.
There are no more uses of "amble" in the book.
Show samples from other sources
The elderly couple likes to amble along the beach at sunset.
A toothless old man came ambling up to them,
J.K. Rowling -- Harry Potter and the Sorcerer’s Stone