Vinegar stops hiccuping because by its heat it vaporizes the surrounding moisture, which prevents belching; for belching takes place when the moisture in the upper part of the stomach is vaporized and concocted, whereas hiccuping occurs when by the action of moisture breath is retained in an excessive quantity in the region of the lungs; for this, gaining impetus and being unable to break through, causes a spasm, and this spasm is called a hiccup.