Wash well, and thoroughly dry, eighteen fine, fresh Long Island smelts. Split them right along the backbone in the centre; remove the backbone of each. Season with a pinch of salt and half a pinch of pepper; sprinkle them with half an ounce of flour, then place them in a pan with one ounce of good butter on the hot range, and fry for two minutes on each side, or until they obtain a good light brown color. Dress them on a hot dish; place in a pan one ounce of good butter, fry it until it becomes of a good nut-brown color; add to it a tablespoonful of vinegar, then pour over the smelts; decorate the dish all around with parsley-greens, and serve.