INTRODUCTION
We have found the excessive calcium content of cow's milk to be a disturbing factor in many of the so-called cases of malnutrition and, as any high protein food made under ordinary conditions from cow's milk will of necessity have the greater part of the protein present as calcium caseinate, it seems to us that although protein was the apparent cause of the toxic condition resulting from the feeding to infants of a high protein milk, the real cause might be due to the calcium chemically combined in the calcium caseinate.We have also found that the feeding to infants of large amounts of pure protein (ash-free paracasin) does not produce any unfavorable symptoms even when the protein is fed with an extremely small amount of whey.1 As this finding may seem to be contrary to the observations of others we have continued our investigation in an endeavor