+---------------+-------+-----------------------+-----------------------+------+ | | | Food. | Output. | | | | +------+-------+--------+-------+-------+-------+ | | | Body- | |Nitro- | Fuel | Nitro-| Nitro-| Nitro-|Nitro-| | Date. |weight.|Total |gen per| Value | gen | gen | gen | gen | | | |Nitro-| Kilo |per Kilo|through|through|through| Bal- | | | | gen. | Body- | Body- | Kid- |Excre- | Hair. | ance | | | | |weight.| weight.| neys. | ment. | |+ or -| +---------------+-------+------+-------+--------+-------+-------+-------+------+ | 1905 | kilos | grams| gram |calories| grams | gram | gram | gram | |Oct. 22-Oct. 31| 18.3 | 9.06 | 0.49 | 80.0 | 7.73 | 0.66 | 0.28 |+0.39 | | 1906 | | | | | | | | | |Jan. 30-Feb. 8 | 17.6 | 5.77 | 0.33 | 78.0 | 4.12 | 0.44 | 0.21 |+1.00 | |Feb. 27-Mar. 8 | 17.9 | 5.31 | 0.30 | 72.0 | 4.59 | 0.59 | 0.37 |-0.24 | |Mar. 27-Apr. 5 | 18.1 | 5.33 | 0.29 | 70.0 | 5.63 | 0.89 | 0.27 |-1.52 | |Apr. 24-May 3 | 18.4 | 5.90 | 0.32 | 68.0 | 5.06 | 0.49 | 0.30 |+0.05 | |May 22-May 31 | 18.6 | 5.90 | 0.31 | 67.0 | 5.25 | 0.53 | 0.43 |-0.31 | |June 17-June 26| 19.9 | 5.89 | 0.29 | 70.0 | 4.29 | 0.39 | 0.28 |+0.93 | +---------------+-------+------+-------+--------+-------+-------+-------+------+ In all of the subsequent months, a small amount of meat was a part of the daily food, but as is seen from the table of balance periods, the total nitrogen intake and the fuel value of the food were reduced to even lower levels per kilogram of body-weight. Yet the animal gained steadily, until at the latter part of June the weight was considerably above that noted at the commencement of the experiment in the preceding October. Further, the animal was in nitrogen equilibrium or even gaining nitrogen, and in perfect condition of health and vigor, as is indicated by the accompanying photographs taken at the different periods stated. Especially to be emphasized is the fact that during the last six months of the experiment, the daily intake of nitrogen and the fuel value of the food were as low or even lower than in November, when the daily diet was limited to bread and lard. The disastrous result which showed itself at once on this latter diet, with all animal food excluded, was not due to low proteid or to deficiency in fuel value, but simply to the fact that the animal for some reason could not adjust itself to a simple dietary of bread and fat, although there was ample available nitrogen and fuel value for the body’s needs. Something was lacking, which meat or milk could supply, and this something was indispensable for the maintenance of the normal nutritional rhythm.