THE UTILIZATION OF ENERGY. 451 
Metab- | 
Fasti . ' Com- _ 
Metabs| eres | Heke? | Ree | Gain, | centage 
Cale oe d Renante Cals. Cals. na 
Cals. |. . 
Proteids (meat): . 
Pettenkofer & Voit.......... 1041 | 13825 | 1225 100 38 | 38.0 
| a on 307 40 13 | 32.5 
4 | 1549 | 1169 | 380] 418 | 110.0 
Rubner stews cisa da steis ee we 944 | 1463 | 1169 | 294 | 332 | 112.9 
l oe 2181 | 1169 | 1012 | 805] 79.6 
43 | 1325 | 920 | 405 | 250) 61.7 
Grube? i.e eiee ves vies { 743 | 1325 | 920| 405 | 296 | 73.1 
Fat: 
. 1086 | 3298 | 1108 | 2190 | 878 | 40.1 
Pettenhofer & Voit........ 554*| 942 | 565 | 377 | 329) 87.3 
554*, 1884 | 565 | 1319 | 837 | 63.5 
ee 1738 | 671 | 1067 | 1016 | 95.2 
942 | 476] 466 | 428] 91.8 
RUD seis whecacd eaters eetese 261 | 3481 266 39 49 | 59.8 
944 | 1549 |} 963] 586 | 540] 92.1 
Starch: 
. 1098 | 2015 | 1220} 795} 353 | 44.4 
Pettenkofer & Voit........ 1098 | 3076 | 1220 | 1856 | 853 | 46.0 
554*| 874, 616] 258 | 137 | 53.1 
Rubner (“ carbohydrates’’, as- 
sumed to be starch)........| 944 | 1549 | 1049 500 | 509 | 101.8 
Cane-sugar : 
Rubner’ giv: <ve sda ae'es view es 451 | 572 | 470] 102] 190 | 186.3 
Cane-sugar and Starch (93 per 
cent. availability) : 
Rubner ............. sated 302 | 702] 825] 877] 365 | 96.8 
While as a whole the results of the computation would seem to 
indicate that the percentage utilization for tissue building is' less 
than the percentage availability, the remarkable range of the 
figures and the uncertain basis upon which they are computed do 
not encourage any attempt at a critical discussion. 
Experiments on Man.—The only respiration experiments upon 
man which the writer has been able to find in which any large 
amount of excess food was given are those of Johansson, Lander- 
gren, Sondén & Tigerstedt + already cited on p. 383 in their bearing 
on the subject of digestive work. If we assume, on the basis of 
* Loss on basal ration. 
+ Skand. Arch. f. Physiol., 7, 29. 
