It has been known for a long time that in the clinical state of edema there is an excess of water and of chlorides in the body. In the case of nephritic edema it has been assumed that the damaged kidneys were unable to excrete these substances and that this was the cause of the retention. Accordingly, it has been customary to restrict sharply the water and sodium chloride intake in the treatment of this type of edema.
But, a priori, the retention of body water and chlorides may be as easily explained by assuming that the body tissues hold them and that they were never presented to the kidneys for excretion. Obviously, it is important to determine which of these hypotheses is correct, since the treatment based on them is entirely different for each.
Experiments were undertaken to determine whether nephritic edema is actually influenced by (a) fluid intake,