NITROGEN BALANCE.—_Underhill._

Nitrogen Output.

Taken in. Nitrogen in Urine. Weight of Fæces (dry).

June 1 6.787 grams. 5.96 grams. 10 grams.

2 6.060 5.81 10

3 7.024 7.30 25

4 7.173 6.78 6

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51 grams contain 5.81 % N.

27.044 25.85 + 2.963 grams nitrogen.

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27.044 grams nitrogen. 28.813 grams nitrogen.

Nitrogen balance for four days = -1.760 grams.

Nitrogen balance per day = -0.442 grams.

Average Intake.

Calories per day 1785.

Nitrogen per day 6.73 grams.

* * * * *

Dr. Arthur L. Dean, Instructor in Plant Physiology in the Sheffield

Scientific School, twenty-five years of age, and weighing 64 kilos,

likewise became a subject of study in this investigation. He is a man of

strong physique, and as an undergraduate student at Harvard University

trained for various athletic events. He began on the experiment October

13, 1903, and continued until April 3, 1904. From October 13th to October

27 he followed his usual dietary habits, simply reducing in some measure

the amount of food consumed. During this period of fifteen days, the

average excretion of nitrogen per day through the kidneys was about 12

grams. On the 28th of October he began to reduce in still greater measure

the amount of proteid food eaten, and gradually diminished the extent of

his proteid metabolism, although not to the same degree as the preceding

subjects. He had full freedom of choice in the character and quantity of

his diet, but his food was characterized by a predominance of vegetable

matter, with an almost complete exclusion of meat.

For a period of nearly six months, or more exactly, from October 28

to April 3, the average daily output of nitrogen through the kidneys

amounted to 8.99 grams, while the average daily output of uric acid was

0.386 gram. This daily excretion of 8.99 grams of nitrogen implies a

metabolism of 56.18 grams of proteid. This, to be sure, means a reduction

in proteid metabolism of about 50 per cent, as compared with the Voit and

other standards, but does not show an economy equal to that practised

by the preceding subjects. It is to be noted, however, in Dr. Dean’s

case, that the body-weight did not show at any time in the experiment a

tendency to diminish. In fact, all through the experiment his body-weight

was a little higher than at the beginning.

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