Skin and bone well three medium-sized soles ; put the fillets in a stewpan, and cover them with salted water, adding a few drops of vinegar. Cook for about six minutes. Then take them off, drain well, and arrange them on a dish. Pour one ounce of melted butter over, with the juice of half a lemon ; garnish with green parsley, and serve with twelve pieces of potatoes a l'Anglaise (No. 988) separate.