A HARD-WORKING DIET. 115 
Daily variations, even during health, in the amount 
of fibrin (No. 2), fat (No. 4), and albumen (No. 9), are 
often considerable, as the “storage” referred to on p. 
21 fluctuates. The fact of such fluctuations is familiar. 
For example, it can be observed with some exactness 
by those who during the training of the University 
crews watch the daily accounts of weights as given in 
all the newspapers, or by those who at Turkish baths 
keep records of their own fluctuations. 
The amount of phosphate of lime (No. 3), probably 
nearly constant, depends mainly on the dimensions 
(partly the density) of the bones, and heredity, feeding, 
habits, and atmosphere, determine this during the first 
eighteen or twenty years of life. The amount of 
fluoride of calcium (No. 12), and phosphate of mag- 
nesia (No. 13) differ from the same cause of individual 
structure. i 
Such a table cannot of course be taken as an exact 
account of the composition of all men of the size, 
weight, and age mentioned. 
The chemical analysis is given first in compounds 
and then as elements. 
COMPOUNDS. 
Ibs. ozs. grs, 
1. Water, which is found in every tissue and 
secretion, and amounts altogether to iN, stOO) G. .O 
2. Fibrin, and similar substances, forming the 
chief solid material of muscular flesh, and 
also occurring in blood ee 5c 5 1) © 
3. Phosphate of Lime, in all tissues and liquids, but 
chiefly in the bones and teeth = ad SulZa. 0 
4. Fat,a mixture of three chemical compounds, 
distributed throughout the body... st eS 0 
Carried forward Ps si, 3 1B7> 54) 0 
