Functional studies of the kidney have afforded many striking possibilities and many interesting problems. The subject is so new, the methods so exact, and the interpretation of results so little understood, that the subject is an ideal one for research.
During the past year, I1 had an opportunity to study with Dr. Frothingham the different nitrogenous diets in chronic nephritis from a functional point of view. In these cases, we found, as has been demonstrated by Widal2 and others, that certain types of chronic nephritis were unable to excrete salt normally. In many cases, 10 gm. of sodium chlorid, when added to the diet, was excreted poorly, or not at all.
Bunge,3 several years ago, in observations on animals and normal individuals, found that the increased intake of potassium salts caused an increased sodium salt excretion, and vice versa. This observation suggested to us the possibility