From the time Pasteur1 showed that volatile fatty acids could be the products of fermentation, the idea of relating them to intestinal peristalsis has interested medical men.2 To pediatricians, however, these acids first assumed real importance during the years just preceding the Great War. At this time the high mortality of artificially fed children in the congested districts was a perplexing problem. Czerny sponsored the idea that volatile fatty acids developed by bacterial contamination of cow's milk were the etiologic factor. Against him were Finkelstein, Salge, Moro, Rietschel and Heubner, who believed other forces to be more important. During the years from 1911 to 1914 convincing evidence was offered in a series of excellent studies3 stimulated apparently by Hans Bahrdt in connection with Huldschinsky, Stafford McLean and others. These investigators, temporarily forgotten in the furor of the war, helped to clear the situation and did much to