Shake all the ingredients extra hard to completely emulsify the egg, then strain into a chilled cocktail glass.
Drinks like this one from the nineteenth or early twentieth centuries that call for egg, egg white, or egg yolk are tricky. The eggs were smaller than our small eggs are today. Following the old recipe instructions that call for a whole egg or the white of an egg with the size of today's eggs will throw the drink out of whack. The solution is to beat the whole egg or the whites and to emulsify it to a liquid form and then measure. In old recipes that call for a whole egg, I use .75 ounce of a small egg.