In 1917 Baumann and Howard published the only metabolism study which has been carried out on guinea-pigs suffering from scurvy, and they are of the opinion that this disorder has a profound effect on the mineral metabolism of this animal. The calcium was excreted in notably large amount; potassium was also lost, and to a greater extent than sodium; the only element which was consistently retained during the active stage as well as during the period of recovery, was magnesium. This study was followed shortly by one from the same laboratory, by Howard and Ingvaldsen, carried out on a monkey suffering from scurvy. It was inconclusive, not conforming to the experiments on the guinea-pigs; the authors state that the "changes in the mineral excretion of the monkey during the scorbutic period were not sufficiently significant to admit of easy interpretation." "The marked loss of the various mineral substances encountered in experiments with man and guinea-pig was not observed in the present series." It should be remembered, however, that the diets of the guinea-pigs and the monkeys were quite different, the former consisting mainly of oats, and the latter of condensed milk. It is quite possible that the basic diet may play a rôle in the metabolism of this disease, although, as stated elsewhere, its effect cannot be noted clinically. Special attention should be paid to this factor in metabolic studies, in view of the widely-held opinion that the carbohydrates exert a potent influence in the development of beriberi. The investigations of the nitrogen metabolism in man and in animals have been most unsatisfactory. The two on human beings--an infant and an adult--were negative; that on guinea-pig scurvy cannot be utilized on account of the restricted diet of oats, which contained insufficient nitrogen, whereas the one on the monkey showed some loss of nitrogen, which led the authors to suggest an increased nitrogenous catabolism in scurvy. This comprises the total data on this subject. Summarizing the results of these few metabolic studies, it may be stated that they harmonize on one point only--the positive balance of calcium during the active stage of the disease. The investigation of Baumann and Howard on adult scurvy, of Lust and Klocman and of Moll on infantile scurvy, and of Howard and Ingvaldsen on the monkey, are all in agreement in this important conclusion. CHAPTER XI RELATION OF SCURVY TO OTHER DISEASES