Calculating the calories per hour on the basis of the calorific value of oxygen for these days and using the average respiratory quotients for the minimum periods, we find that on the first day of the first experiment the values are 36.7 calories per hour, 1.54 calories per kilogram per hour, and 37.3 calories per square meter per hour. For the minimum periods on the third day of the third experiment the values are 33.8 calories per hour, 1.48 calories per kilogram per hour, and 35.3 calories per square meter per hour. The nitrogen excretion in the two days was for the first day 0.216 gram per hour during the period of minimum metabolism, and on the last day 0.20 gram. As these are essentially constant values, we may disregard them in our computation of the total metabolism.

From these figures it is seen that on the two days the metabolism, both per unit of body-weight and per unit of body-surface, was essentially constant, i. e., a difference of but 4 to 5 per cent. Thus the entire argument of Falta, Grote, and Staehelin falls to the ground when based on these experiments, as the results can not be used for positive proof of the assumption that with long-continued undernutrition there is an adjustment of the body to the lower food intake.

Staehelin, 1909

In an interesting address dealing specifically with the problem of the lowering of metabolism, Staehelin1 cites many of the cases in literature in which normal individuals showed a lowered metabolism and definitely emphasizes the fact that there may be an adjustment of the metabolism to the nourishment.

1 Staehelin, Deutsch. med. Wochenschr., 1909, 35, p. 609.

Hunt, 1910. The effect of a restricted diet upon the resistance of animals to certain poisons was studied by Hunt1 in an extensive series of experiments on mice and guinea-pigs. The author assumes that acetonitrile exerts its toxic effects only, or largely, after undergoing changes due to the processes of metabolism, the intensity of the processes of oxidation determining the intensity of the toxic effect. The diet given the experimental animals, while qualitatively the same, was less than that of the animals on the unrestricted diet. The dose of acetonitrile dissolved in water was injected subcutaneously; the amount used was proportional to the body-weight. Only those experiments in which the dose was nearly fatal are cited. It was ascertained as typical of these experiments, that with equal doses of acetonitrile the animal on an unrestricted diet died, while that on the restricted diet recovered. This was interpreted as showing a diminution in the intensity of the processes of metabolism with restricted diet.

Grafe, 1910

In his first publication on metabolism during katatonia, Grafe2 points out that in spite of what he considers sufficient food, namely, 1,400 calories per day, the body-weight remained constant at 47.5 kg. as compared with an initial weight of approximately 55 kg. He concludes that the body does not exhibit a tendency to increase in weight, and considers this as possibly a peculiarity of katatonia. We have here one of the earliest suggestions in Grafe's writings of the conception of an adjustment of metabolism to food intake, viz., that with increased food intake there is increased energy expenditure.

Grafe, 1911

In a special search for pathological conditions in which a retardation of basal metabolism would be noted, Grafe,3 in a carefully planned series of experiments, studied the metabolism of patients in psychiatric coma. Obtaining his subjects from the Psychiatric Institute in Heidelberg, he placed them in the Jaquet respiration chamber in the Clinic for experiments lasting from 3 to 12 hours or more. If we consider only those experiments in which the subjects remained very quiet, we find in certain cases of mental disturbance accompanied by stupor that the basal metabolism, either per kilogram of body-weight or per square meter of body-surface (using the Meeh formula), is extraordinarily low. In one case it was 39 per cent below 'the value selected by Grafe as a normal, namely, 800 calories per square meter per 24 hours.

Grafe finds it difficult to explain this depression in metabolism as being caused by chronic undernutrition. Grafe's patients, although admittedly somewhat undernourished when compared with the average of normal people of the same age, were far from being emaciated. It so happens that the most pronounced depression in metabolism occurred with a woman with a height of 162 cm. and a weight of 71 kg., who was in an unusually good state of nutrition. Recognizing the difficulties of interpreting this phenomenon, Grafe cautiously states that the experiments simply establish the fact that with mental disease there is a true depression in the metabolism. His experiments on subsequent feeding are somewhat less numerous and indicate that while the maximum effect following food may not appear so soon as with normal people, the total increase in oxidation as the result of food ingestion is essentially normal.

1 Hunt, Public Health and Marine-Hospital Service of the U. S., Hygienic Laboratory Bull.

No. 69, 1910. 2 Grafe. Zeitachr. f. physiol. Chem., 1910, 66, p. 45. 3Grafe, Deutsch. Arch. f. klin. Med., 1911, 102, p. 15.

It is quite clear, therefore, from this study of Grafe's, that the basal metabolism during conditions of mental disturbance accompanied by stupor may be very considerably lowered. The lowered values are so great that they can not be ascribed to errors in the selection of a normal value or to a possible error in the body-surface values as compared with the more recent body-surface standards of Du Bois. As an indication of the possibility of alteration in basal metabolism the investigation has a profound interest. Since the majority of Grafe's patients were not unduly emaciated, it is quite likely that we deal here with a specific result of the mental condition accompanied by stupor and not to a distinctly undernourished condition of the body with lessened cell-mass.