382 PRINCIPLES OF ANIMAL NUTRITION. 
Experiments on Man.—Magnus-Levy’s experiments upon man 
were made substantially like those upon the dog, the subject lying 
upon a sofa, as completely at rest as possible, and breathing through 
a mouth-piece. 
Fat.—Two experiments with fat, computed in the same way as 
those upon the dog, gave the following results: 
H Heat Production in 24 Hours. 
Fat Energy 
No. of Experiment. Eaten, | of Food, Increase. 
Grms. Cals. Fasting With 
Cals. "| Food, 
= Per Cent. 
Cals. | of Food. 
Slec seeks tasees 94.0 893 1537 1547 10 1.12 
QE vo aiuad Mecano 195.6 1855 1524 1582 58 3.13 
CARBOHYDRATES.—Numerous experiments on a man were made 
in which the diet consisted chiefly of bread, and a smaller number 
in which the effect of sugar was studied. With bread the increase 
in the metabolism was more prompt than in the experiments on the 
dog, but smaller in amount, varying from about 12 to as high as 33 
per cent., according to the amount eaten. By the end of the third 
hour the effect had nearly disappeared, but it was then followed 
by a second increase, less in amount but continuing longer, which 
the author suggests may have been due to the commencement of 
intestinal digestion. With sugar (both cane and grape) the increase 
was equally prompt, although rather less in amount, but dis- 
appeared entirely after two or three hours. None of the experi- 
ments extended over more than ten hours and usually over less, and 
the data given are insufficient for a satisfactory computation of the 
total increase for the twenty-four hours. The respiratory quotient 
was considerably raised, but did not reach 1.00 in any case. 
ProtTeips.—Experiments upon the effect of proteids on the 
respiratory exchange yielded results similar to those obtained with 
the dog, but do not permit of a satisfactory computation of averages 
for the twenty-four hours. 
Mrxep Diet.—Results with a mixed diet the ingredients of 
which are not specified have been reported by Johansson, Lander- 
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