Crock Pot Vegetable Beef Soup

1 to 2 pounds beef short ribs or ox tails
1 can tomatoes
2 sliced carrots
3 ribs diced celery
2 medium onions, diced
6 potatoes, peeled and diced
3 cups water
1 teaspoon salt
4 peppercorns
3 beef bouillon cubes

Stir well in a crock pot and cook, covered, on LOW for 8 to 12 hours; on HIGH for 4 to 6 hours.