The value of cod liver oil in preventing and in curing rickets has been heralded with extreme enthusiasm during the past few years, and recent literature has been filled with reports of investigations concerning its action, and concerning its apparently close relationship to the action of ultraviolet irradiation. As might be expected, the interchangeability of cod liver oil and ultraviolet therapy has been overrated, for rational investigations, notably those of Wilson,1 have shown that infants receiving apparently sufficient doses of cod liver oil will develop rickets in almost as high a percentage of cases as will those not so treated. The value of the oil seems to be one of control rather than of prevention, the infants receiving it manifesting rickets that healed earlier than that in the infants of the control series.
Despite the fact that the serum concentration of calcium, and especially of inorganic phosphorus, has generally