Green’s Dictionary of Slang

an act of urination.

1935		A.J. Pollock Und. Speaks n.p.: Rattle and hiss, urine.
1944		Maurer & Baker ‘“Aus.” Rhyming Argot’ in AS XIX:3.
1960		J. Franklyn Dict. Rhy. Sl.
1972		Dodson & Saczek Dict. of Cockney Rhy. Sl.
1978		Maledicta II:1+2 (Summer/Winter) 117: There are other, more general if less modern and correct, studies of Cockney rhyming slang, though they tend to skirt Tom Tit (‘shit’), rattle [and hiss] (‘piss’), you and me (‘pee’) and me and you (‘screw’).