Well, medically speaking hiccups are caused by irritation of the nerve supplying the diaphragm (which is a muscle that separates the chest from the abdomen), the phrenic nerve. And you don't need to take water for it to stop. When next you experience a bout of hiccups, just hold your breath for a few seconds (works on the principle of increasing carbon dioxide concentration, which also occurs when you swallow water as the airway is closed). Nice write up though.