Kumagawa,[12] studying especially the diet of the Japanese and experimenting on himself (27 years old and weighing 48 kilos), found with a purely vegetable diet, containing per day 54.7 grams of proteid, 2.5 grams of fat, and 569.8 grams of carbohydrate, that he showed for a period of nine days a plus balance of nitrogen, indicating that his body was laying on about 4 grams of proteid per day. The nitrogen excreted per urine and fæces amounted to 8.09 grams per day, while the nitrogen in the daily food amounted to 8.75 grams. It is interesting to observe in these experiments, as indicating the degree of absorption of the vegetable food (composed in large measure of rice) that the daily average of nitrogen in the urine amounted to 6.069 grams and in the fæces 2.029 grams. In other words, of the 54.7 grams of nitrogen-containing food only 37.8 grams were absorbed, 12.69 grams passing out with the fæces. The total fuel value of the absorbed food per day was 2478 large calories. Similarly, Hirschfeld[13] has called attention to the fact that with many vegetable foods especially, not more than 75 per cent of the ingested proteid can be digested and absorbed, thus emphasizing the necessity of paying heed to the _character_ of the proteid food in considering the nutritive value of a given diet. In some experiments reported by C. Voit[14] in 1889, on the diet of vegetarians, E. Voit and Constantinidi found that nitrogenous equilibrium was established in one man with about 8 grams of nitrogen, corresponding to 48.5 grams of proteid as the daily diet, with large amounts of starchy foods and some fat. Similarly, Nakahama[15] in the same year, studying the diet (mostly vegetable) and nutritive condition of thirteen German laborers in Leipzig, found that their daily food contained on an average 85 grams of proteid, but Carl Voit criticising these results states that the men were of comparatively light body-weight—about 60 kilos—and not well nourished. Kellner and Mori,[16] studying the nutrition of a Japanese (weighing 52 kilos and 23 years of age) state that on a purely vegetable diet containing 11.34 grams of nitrogen, of which only 8.58 grams were digested, there was a distinct loss of body-weight, with a daily loss to the body of 1.16 grams of nitrogen. On a mixed diet, however, containing fish, it was possible to establish nitrogenous equilibrium with a daily diet containing 17.48 grams of nitrogen, of which 15.27 grams were digested and utilized. Similarly, Caspari,[17] 29 years old and weighing 66.2 kilos, found that while he could maintain his body in nitrogenous equilibrium on 13.26 grams of nitrogen per day, he could not accomplish it on 10.1 grams of nitrogen, though his daily food contained 3200 large calories.