The introduction of standard test diets into clinical medicine has distinctly advanced our knowledge of human metabolism and furnished many useful data for diagnosis, prognosis and treatment. Such are the Ewald test breakfast, the diet of Schmidt and Strassburger for the study of diseases of the gastrointestinal tract and the proteid-fat diet employed in diabetes. Although these various diets were excellent, they threw light on only the more superficial phenomena of metabolism, and it was to be expected that other variations in the diet would be planned which would penetrate into the more fundamental processes of the body. It is to the credit of Taylor1 that he devised such a diet in 1904 and had the temerity to live on it until unusual symptoms occurred.
Admirable as was the conception and interesting as were the results of Taylor's experiments with an ash-free diet, one of his observations and the interpretation