Much labor has been expended, by very many observers, upon the analysis of the _urine_ in connection with cancer, as that might be expected to reveal the metabolic changes connected with this disease. While many departures from the normal have been reported, and while under complete volumetric analysis the urine of a subject of cancer is rarely if ever that of health, it cannot be said that any definite and specific changes have been established which may not be found in those without cancer; although there have been several who have so claimed even diagnostic signs from the urine. But minute, volumetric analysis is often of great service in guiding the nutrition and medication of these patients, and gross errors are continually met with, which have the greatest bearing on the case in hand, as indicating very great metabolic disturbance: and constantly the urinary excretion will be found to be extremely deficient, both as to its quantity and its total solid elimination. In one very interesting case of cancer of the breast, in a stout, flabby lady, near 55, in private practice, the total daily quantity of the urine, measured for weeks, is always very far below the normal amount; and in spite of active medication it seems almost impossible to raise the total daily solids excreted in the urine, to more than one-half of that called for by the weight of the patient. We may now briefly consider some salient points reported in connection with the urine in cancer. As remarked in regard to other elements in the study of the disease, it would be very desirable to have a knowledge of the urine in pre-cancerous stages of health, or ill health, and also in very early cancer, likewise after surgical operations, that we might better understand the metabolic changes which lead up to malignant disease; but unfortunately these are exceedingly few and unsatisfactory, and almost all the studies have been made in advanced cancer, and often when the disease has affected vital organs, or when by its own poison it has disturbed the workings of the economy. Many observers agree that there is a disturbance of proteid metabolism in cancer, and dependent upon this many deviations from normal are found in the urine, some of which in turn are related to the inanition which occurs. The _urea_ is almost invariably diminished, often very greatly, as I have verified time and again in many cases.