Harry of Ciro's ABC of Mixing Cocktails by Harry of Ciro's (1923, p.80) — Harry of Ciro's 1923

1 glassAbsinthe base
1 whiteegg white — Fresh Egg Whitebase
1 dashSoda water — Syphondilution
1 teaspoonfulAnisette syrup — Anisette Syrupsweetener
  1. Shake well together and strain into small wine glass.
  2. Add a dash of syphon on top.

This matters because it preserves another morning-after absinthe bracer in a British hotel-bar source.

The dash of syphon added on top is part of the service ritual here.

See also: Suissesse, Absinthe Cocktail