Heat a ceramic fondue pot over medium-low heat. Once the pot is warm, rub the inside of the pot with the garlic clove. Pour the white wine and lemon juice into the pot. Mince the remainder of the garlic clove and add it to the pot. Stir in the Gruyere cheese, Emmentaler cheese, Jarlsberg cheese, and smoked Gouda cheese, a handful at a time, stirring constantly until all the cheeses are melted and the sauce is smooth.
Whisk together the cornstarch, nutmeg, and balsamic vinegar, and stir into the cheese sauce. Continue to heat while stirring, until thick and smooth. Keep fondue warm over low heat. Serve with French bread.