(Reading). Drinking gin or whisky.
“ `Why, John,' said the veteran, `what a discipline is this you have been keeping? You have been reading Geneva print this morning already.' `I have been reading the Litany,' said John. shaking his head, with a look of drunken gravity.” —Sir W. Scott: Old Mortality, chap. xi.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
More on Geneva Print from Infoplease: