This is the diabetes insipidus of some writers. By this term is understood the excessive secretion of pale, limpid urine, without sugar. The principal symptoms are insatiable thirst and the elimination of a large quantity of urine. These symptoms are usually preceded by a variable appetite, constipation, and derangement of the functions of the skin. The copious flow of urine may only be occasional, following over-mental or physical excitement. It may be distinguished from diabetes mellitus by the absence of sugar in the urine.

TREATMENT. -- The skin should receive special attention, and excess of drinking should be avoided. The constitutional debility should be overcome with baths, and the general tonics; apocynin, from one-eighth to one-fourth of a grain, four or five times a day, is a specific for this disease.