Green’s Dictionary of Slang

a drink of brandy and soda.

1861		Once a Week V 528/2: The next morning, just as I was doing some soda and B, in rushed her brother, the old major, shook me by both hands, and went off at score in the heavy father style.
1864		‘Quite Alone’ in All the Year Round 169/2: Been drinkling oceans of soda-and-B., and getting very spooney [...] Keep him off champagne. It’ll drive him mad. Keep him on his soda-and-B.
1873		‘Cuthbert Bede’ Little Mr. Bouncer 91: I must restrict myself to devil and soda and B.
1875		‘Aliph Cheem’ Lays of Ind (1905) 142: Then came cards, and soda-and-b.
1877		‘’Arry on His ’Oliday’ in Punch 13 Oct. 161/1: The ‘bitter’ round here is just lummy, and as for their soda-and-B, / It’s ekal to ‘fiz,’ and no error.
1883		Bristol Magpie 22 Mar. 6/1: Give him [...] a ‘soda and B.,’ a big cheap cigar, and plenty of room to expectorate, and he is content!
1895		F.B. Dovetton Fisherman’s fancies 93: Should he tell me all about it over a weed and soda and B? Would it interest me to hear it ?