Green’s Dictionary of Slang

(US) a female breast; often in pl. jerseys.

1935		A.J. Pollock Und. Speaks n.p.: Jersey Cities, a woman’s breasts.
1944		Maurer & Baker ‘“Aus.” Rhyming Argot’ in AS XIX:3.
1978		Maledicta II:1+2 (Summer/Winter) 118: Elsewhere Aylwin lists a few more ‘Vulgarities’: [...] words for breasts (brace and bits, east and west, Jersey City, thousand pities, towns and cities, fainting fits).