Mr H. F. Baxter on Muscular Power. Pali 
proper and fit state for healthy nutrition. Excessive secre- 
tion, as during lactation, many exhaust the vital powers 
in the same manner as excessive nerve action or mus- 
cular action, but we must bear in mind, when applying 
the principle of Conservation of Force in the explanation 
of natural phenomena, the distinction between the jorma- 
tive action by which the force is generated and the disin- 
tegrating or destructive actions by which the force is ex- 
pended. The analogy which is drawn between the steam- 
engine and the animal body is too far fetched, if we 
compare the food and fuel on the one hand and the lungs 
and the furnace on the other: the respiratory function 
is not an act by which the vital force is generated, although 
it is one by which it is maintained. We cannot say 
that the vital force of the animal is generated, or ori- 
ginates in the combustion of the carbon which takes place 
in the lungs, as the power of the steam-engine originates 
in the combustion of the fuel which generates the heat ; 
that which is primary in one is secondary in the other. 
During muscular action—the development of muscular 
power—we have heat evolved, chemical action taking place 
and electricity evolved, but we are not justified in saying 
that the mechanical power of the muscle is converted into 
chemical force, or into heat, or into electricity. It would 
be more in unison with the facts if we say that the mus- 
cular force developed and generated during the nutrition of 
the muscle is converted into mechanical power, heat, elec- 
tricity, and chemical force, during muscular action. But we 
should naturally ask, What do we mean by muscular force ? 
In what does it differ from mechanical power? And this 
shows us the impropriety of assuming what are mere pro- 
perties to be forces. The term conversion gives but an 
inadequate idea of what is intended to be conveyed, and 
consequently inappropriate. The relation which heat, elec- 
tricity, and chemical action bear to the power exerted by 
the muscle, in other words, their relative equivalents, is the 
point to be ascertained. 
Similar observations may be made in regard to nerve 
force. Nerve force is generated and maintained during 
nutrition, and expended during nerve action. Nerve action 
