"up the spout"

Does somebody know where the phrase "up the spout" or "shove it up the spout" comes from? I've been seeing a lot in P.G. Wodehouse to refer to pawning something and was wondering where it came from.

I saw a few references stating that "spout" used to mean the device ( lift, for those in Blair Land ) used in a pawnshop for sending deposited articles up for storage.

So if anything - or, by transference, anybody - is up the spout, there are difficulties.

Is the mirror image of this called "going down the tubes"?