Cheerio! A Book of Punches and Cocktails by Charles (1928, p.14)

2 partsdry gin base
3 dashesorange bitters bitter
3 dashesonion juice dilution
1 partFrench vermouth — French Vermouthmodifier
ice — For shaking.other
  1. Combine the dry gin, French vermouth, onion juice, orange bitters, and ice in a shaker.
  2. Shake well, strain into a cocktail glass, garnish with an olive, and serve.

Garnish: Olive

Ice: Ice

See also: Martini Cocktail, Tom Gin Martini

Source garnishes with an olive.