I posted about his once before, but Dickens here uses it evidently to mean what I have heard called a "Lazy Susan".

"I bought a second-hand dumb-waiter for this dinner-party, in preference to re-engaging the handy young man; against whom I had conceived a prejudice, in consequence of meeting him in the Strand, one Sunday morning, in a waistcoat remarkably like one of mine, which had been missing since the former occasion. The 'young gal' was re-engaged; but on the stipulation that she should only bring in the dishes, and then withdraw to the landing-place, beyond the outer door; where a habit of sniffing she had contracted would be lost upon the guests, and where her retiring on the plates would be a physical impossibility. "

Dumb-waiter
(n.) A framework on which dishes, food, etc., are passed from one room or story of a house to another; a lift for dishes, etc.; also, a piece of furniture with movable or revolving shelves.



Lazy Susan

Axis-mounted shelves that revolve. Also called carousel shelves.