In a saucepan bring the milk and the cream just to a boil. In a bowl whisk together the eggs, the sugar, the nutmeg, the salt, and the vanilla, whisk 1/2 cup of the milk mixture into the egg mixture, and whisk the mixture into the remaining milk mixture. Cook the custard over moderate heat, stirring constantly with a wooden spatula, until it registers 175°F on a candy thermometer. Transfer the custard to a metal bowl set in a larger bowl of ice and cold water and stir it until it is cold. Freeze the custard in an ice-cream freezer according to the manufacturer's instructions.