The Hoffman House Bartender's Guide by Charles S. Mahoney (1905, p.141)

0.5 lemonlemon juice — juice of half a lemonbase
1 jiggerPlymouth gin base
Soda water — syphondilution
1 teaspoonfulcream other
0.5 teaspoonfulpowdered sugar sweetener
  1. Shake the lemon juice, powdered sugar, Plymouth gin, and cream well.
  2. Pour into a split glass, use syphon, and drink while effervescent.

Mahoney specifically emphasizes immediate service while still effervescent.

See also: Gin Fizz, Silver Fizz