Green’s Dictionary of Slang

dog’s nose n.1

also dawg’s nose, dognose
[like the animal’s nose, the drink is black]

1. [19C–1900s] beer warmed nearly to boiling, mixed with gin or wormwood (the basis of absinthe), sugar and ginger; an alternative version substitutes brandy for the wormwood.

2. [mid–late 19C] an alcoholic whose preferred tipple is whisky.