


AVAILABILITY AND FUEL VALUE OF FOOD MATERIALS. 107 
and those actually found by experiment may of course be due 
to compensation of errors, and when a large number of experi- 
ments are compared in the same way the results may prove 
less strikingly concordant, but it seems hardly probable that 
the proposed factors for heats of combustion and fuel value 
can be very far out of the way. 
TABLE LI. 
Comparison of heats of combustion and fuel values of nutrients 
of food consumed in digestion experiments as calculated by 
use of the proposed factors and as found by experiment. 


|| 










: #48 | asd || 2 ea | aed 
= i acta ee hy: ly ra ea Soe Q 
o aaa | Beas ges | oy CHARACTER EBEe ges 
M pease Bo bell 6 os Ofue) 8p 
7 | EXPERIMENT.* |S2°°O|) a5 || YY | Experiment.* | 38°90] 2.5 
“a mye BSqye il ay ° 3-H] SYS 
3 pa eee ete. Woo tele ieee a 
: | So Urs Oey} , Ca Ur Tom) 
= dota an S Peau aie 
fo he fo % 
37 | Ordinary, salOd ede LOL. 4 i Sir) Ordinary, evi LOO. 4” te FO Tf 
Zor uxespiration, - | 101..2/) 101.8 |/' 52° | Respiration, - 99.9 99.3 
39 | Ordinary, - 99.3 98.1 || 76 | Ordinary, PU LOO:.7 98.8 
40 | Respiration, - 99.4 97.9 || 77.| Respiration, - 9979 4L00 63 
41 | Ordinary, - | 102.1 | 103.1 || 78 | Ordinary, - 90. bmogee 
42 | Respiration, - ; 102.5 | 100.2 || 79 ; Respiration, - | 99.4 | 98.9 
43 | Ordinary, - 99-7 | 100.3 || 80 | Ordinary, = 98.9 | 99.4 
44 | Respiration, - 99.8 99.0 || 81 | Respiration, - 95. 7peageag 
_45.| Ordinary, - | 100.2 | 103.1 || 82 | Ordinary, - 99.3 99.0 
46 | Respiration, - | 100.2 | 101.7 || 83 | Respiration, - 99-4 | 99.2 
47 | Ordinary, - | 100.7 | 100.7 || 84 | Ordinary, - 98.5 98.3 
48 | Respiration, - | 100.6 | 102.0 | 85a) Respiration, - 98.7 98.6 
49 | Ordinary, - | 101.0 | Io1.8 || 85b/ Respiration, - | 98.6 | 98.9 
50 | Respiration, - | 101.0 | 102.4 || | Avg. 27 expts.| 100.0 | 100.1 


* These twenty-seven experiments were made in connection with investigations 
with the respiration calorimeter. Those marked ‘‘ ordinary ’’ were conducted outside 
the apparatus, and immediately preceded the respective ‘‘ respiration’ experiments 
in which the subject was inside the respiration chamber. 
COMPARISON OF FACTORS HERE PROPOSED WITH THOSE PRO- 
POSED BY RUBNKER. 
The factors for fuel value now in most common use are those 
proposed by Rubner,+ in 1885. This investigator assigns 4.1 
calories per gram to the protein, 9.3 to the fats, and 4.1 to the 
carbohydrates of ordinary mixed diet. 

TiZASCHY, Biol 21° (1885); PD. 377-.>. 
