Café Royal Cocktail Book by W. J. Tarling (1937, p.210)

0.3 partCalvados — Calvados (Un Trou Normand)base
0.4 partgin — Ginbase
0.2 partgrapefruit juice — Grapefruit Juicegarnish
0.1 partvan der hum — Van der Hum (Sedgwick)modifier
  1. Shake and strain.

Invented by Tony O'Connor.