The action of the _kidneys_ is also always a very important element to watch and control in cancer patients; this does not have reference to albumen and casts, or glycosuria, but to a functional derangement of the secretion: for the former are relatively infrequent compared to the latter. This is so large a subject that time does not permit of its elaboration; I made the matter pretty clear to you in my lectures not long ago on the relations of diseases of the skin to internal disorders. I must tell you, however, that, as a result of numberless studies of the urine of many cancer patients, I have almost constantly found a deficient or defective urinary secretion: in many cases I have had the total daily amount accurately measured, and reported in writing each week over long periods, and while the total quantity may at times be near normal, the total solids sometimes fall to, and remain at, even less than one-half the amount which should be passed for the patient’s body weight. I want here to urge upon you the importance and value of repeated volumetric examination of all possible ingredients of the urine, as indicating in the best manner obtainable the state of the arterial blood, from which the urine is derived: especially is this true of the exact volumetric acidity, representing the diminished alkalescence of the blood common in cancer. The actual medicinal and dietary treatment of the various possible departures from normal can hardly be elaborated here, but they are along very much the same lines which you have often watched in connection with certain diseases of the skin; for you must remember that carcinoma is an epithelial disease, and that the laws of nutrition are much the same for this as for various other morbid conditions of the economy. I may say, however, that very many of my cancer patients have received the greatest benefit from acetate of potassa, often in the formula familiar to you (℞ Potass. Acetatis ℥i Tinct. Nucis Vomic ʒiv Extr. Cascar. fld. ʒ‾ij‾-ʒiv Extr. Rumicis radicis fld. ad ℥iv M. Sig. One teaspoonful half an hour before eating, well diluted). For many years I have administered potassa largely to these patients, and it is gratifying to find not only support but an incentive to its greater use, in the studies and experience of Ross, who pushes it to a very great extent, giving as high as 240 grains of potassium phosphate in a day. Ross also advises the free use of crude or brown sugar, as it contains a large proportion of potassium salts, which are for the most part removed from the white or refined article. I must also remind you of the great value of Bethesda water, in washing out the kidneys, given a tumblerful with each meal, and one tumblerful, hot, one hour before breakfast and also an hour before the evening meal.