Diabetes insipidus has been defined as a "chronic affection characterized by the passage of large quantities of normal urine of low specific gravity."1
The condition has been recognized for a long time, and the literature on the subject is large. Little, however, is found which bears on its study by the newer laboratory methods. Pathologists have furnished little gross or microscopic evidence as to the nature of this affection, except in those cases of the so-called "symptomatic type" in which an organic lesion in the brain has been found as a possible cause.
Experimentally, the possibility of a central origin for the condition has been suggested. Thus it has long been known that puncture of the floor of the fourth ventricle may produce a polyuria. No definite center for the control of polyuria, however, has been found.
Disturbances in the ductless glands have been suggested as the cause of this