Peel and cut coarsely the carrot. Peel the onion and cut into quarters. Wash the fish, dry. Mix one lemon juice, 700 milliliters of water, onion, carrot and bay leaf, bring to a boil, add the salmon and stew for 4 minutes. Wash another lemon and slice. Wash and dry dill. Remove the fish from the broth, put in the warm place. Strain the broth, take 375 milliliters . Melt the butter in a pot, add the flour, fry gentle, pour the broth and stir( without lumps). Add cream and horseradish. Bring to a boil, pour wine, salt, pepper and add sugar to taste. Serve the fish with sauce, dill and a slice of lemon.