Green’s Dictionary of Slang

1. (Aus./US) a (foolish) braggart, a talkative person.

1854		Life in Boston & N.Y. (Boston, MA) 13 May n.p.: You are a regular gas-pipe.
1857		Bell’s Life in Victoria (Melbourne) 28 Feb. 3/6: Unless he accepts the challenge, I shall consider him a gas pipe, and the greatest coward that «ever disgraced tho prize ring.
1868		Chelmsford Chron. 17 Dec. 7/1: [from N.Y. Tribune] He is thus addressed: ‘Good bye, old windy; good bye old gaspipe; go home and soak your head in whisky.
1869		Sportsman (London) 16 Dec. 2/1: Notes on News [...] He is spoken of in one [NYC] newspaper as ‘an addlepated swindlebug,’ and in another is addressed thus:—‘Good bye, old windy; good bye, old gaspipe; go home and soak your head’.
1898		(con. 1860s) C.H. Crawford Earlier Days 96: I think you are a regular gaspipe [HDAS].
1919		DN V 65: Gas-pipe, one who talks a great deal.
1934		C. Drew ‘The Unbeliever’ in Bulletin (Sydney) 13 June 50/3: ‘Don’t call me a gaspipe,’ said Redhead, flushing up. ‘Rats!’ jeered Slugger. ‘You’re only a windbag’.
1945		E. Wilson I Am Gazing Into My 8-Ball 125: Frederics [...] said to me, ‘But I guess I’m just an old gas pipe.’ He meant he liked to gas, I suppose .

2. the voice; verbosity.

1856

Life in Boston & N.Y. (Boston, MA) 25 Oct. n.p.: Dry up, Bill, and stop your Irish gaspipe, or you may get what Paddy gave the drum.