Some affection of mind is usually present in chronic alcoholism. Commonly it is moderate in degree, and may be shown only in weakened will-power and failure of memory. In delirium tremens, more intense, but transitory, disorders occur; and in relatively rare instances alcoholism seems to be responsible for a chronic insanity with persistent delusions, usually of persecution and jealousy. " In general, however, the part which alcoholic excess plays in the causation of the ordinary forms of mental disease is of secondary importance: it has been shown that when the two things are associated, intemperance is more usually a symptom of insanity than its cause."1