Place corned beef and water in Crock Pot Cooker.Cover.Set on high.When steaming vigorously,set to medium and continue cooking 2.5 hours. Remove meat from cooker.Put potatoes, turnips,carrots and cabbage in Cooker.Place meat on top of vegetables.Cover and when mixture is steaming briskly,set to medium.Cook for 45 minutes. Ham may be used in place of corned beef,if desired.