Jibber jabber

Where did the phrase "jibber jabber" come from? I need the year it first appeared. Also, where did the phrase "I haven't the foggiest idea" come from?

As for the second part, something that is 'foggy' is unclear, hard to discern - for fairly obvious reasons - so a foggy idea (if such a phrase existed) would be a vague one.

Not having even the 'foggiest' idea is having no idea at all; not even a badly formed, undefined one.

DFG

Jibber-jabber is a coupling of "jibber" and "jabber", which are themselves variants of the same onomatopoeic verb meaning "To speak rapidly and inarticulately; to chatter, talk nonsense". "Jibber" (spelt "gibber") was used by Shakespeare; "jabber" is recorded in 1499. (There are a number of similar words in English all meanig much the same thing - e.g. gabble, yabber, gab, jabble.) The earliest sighting of "jibber-jabber" recorded in the Oxford English Dictionary is in 1922, but that doesn't mean that was "the year it first appeared". Given English-speakers' love of reduplicated words (e.g. helter-skelter, hanky-panky, roly-poly, willy-nilly, hocus-pocus), coupling "jibber" and "jabber" would have been a natural formation at any time in the last 400 years, and it may have been commonplace for many years before it finally appeared in print. (VSD)