Quantitative determinations of minerals excreted by the skin of infants have received little consideration in the literature. Only one paper by Rominger and Meyer,1 which bears directly on this subject, has come to our attention. A number of papers2 deal with the mineral content of the sweat in the normal adult, in the sick adult and in the adult in whom sweating was induced artificially.
Rominger and Meyer1 determined the combined amount of sodium and potassium as chlorides excreted through the skin of an infant fed on cow's milk. They concluded that the amount of sodium and potassium lost through the skin did not materially affect the differences in retention of these elements obtained in the breast-fed infants and in those fed cow's milk. In our extended study of this problem, it was our object to determine separately the amount of sodium, potassium, chlorine, calcium and phosphorus