Dice salt pork and brown in 3-quart kettle or saucepan until crisp. Add onions, and cook 2 minutes. Add potatoes and water. Cover and cook 10 minutes. Flake fish coarsely and add with milk and butter or margarine. Simmer until potatoes are tender. Add salt and pepper to taste. Place crackers in soup plates and pour chowder over them. Yield: 6 generous servings.