This cocktail is actually what led me into researching a somewhat distant variant, the Monkey Gland. I first came about them both in Dr. Cocktail’s very enjoyable book “Vintage Spirits & Forgotten Cocktails.” The ingredients for the Income Tax are easier to find, so it’s more likely you’ll be able to try one of these out with even a modest liquor collection.
1 1/2oz gin
1/2 oz sweet vermouth
1/2 oz dry vermouth
Juice of 1/4 orange (about 3/4 oz)
dash of angostura bitters
Shake with ice, strain into cocktail glass and garnish with an orange wheel.