A HARD-WORKING DIET. FEY 
They regarded the theory that “muscular action was 
brought about by chemical changes alone,” as having 
found such acceptance it might be said to be a 
_universally acknowledged fact. That these chemical 
changes were processes of oxidation they thought 
almost equally well established, but the exact point 
as to what element it was whose oxidation gave 
origin to muscular power was still a matter of doubt, 
demanding further experiments. They allude to the 
recognition that the mechanical work of muscles 
represented only a@ part (see p. 37) of the actual 
energy resulting from the oxidation of the carbon or 
nitrogen or whatever it was. The limits of the 
problem narrowed down practically to this—was it 
the oxidation of nitrogen or of carbon which furnished 
the store of energy? Smith’s experiments, referred 
to above (p. 20), they did not regard as a direct 
disproof that waste of tissue by the oxidation of 
nitrogenous matter was the source of power. (Refer- 
ence to Voit and Bischoff.) They proposed to them- 
selves direct experiment. Here is their own state- 
ment, with some few omissions, as rendered in English 
in the ‘ Philosophical Magazine.’ 
There is one way in which the question whether 
muscular force can be generated only by the oxida- 
tion of albuminoid compounds* might be decisively 
negatived, and that possibly by a single experiment. 
It is suggested by the following simple line of thought : 
granting that a person might accomplish a certain 
measurable amount of external labour, say m métre- 
kilogrammes, and that in so accomplishing it he 
oxidized grammes of albumen in his muscles ; 
* For composition of albumen, see p. 27. 
