During the past three years, we have been feeding the rachitic infants in St. Mary's Hospital on hydrochloric acid milk. We have observed that the rachitic bones in these infants healed much faster than when any other formula was used. During this time also we have fed routinely over 325 normal infants on hydrochloric acid milk throughout the first year and have never seen a case of rickets develop in this group.
Because of these observations, we decided to study the calcium metabolism in both rachitic and normal infants fed on sweet milk and acidified milk mixtures.
L. E. Holt, Jr.,1 and his co-workers showed that the rachitic infant is unable to retain much of his calcium intake, but when cod liver oil is added to his dietary the calcium retention rapidly increases. We wished to see if we could bring about the same results merely by giving the