Conservation and Innovation : Helmholtz's Struggle with Energy ...

" ...the quantity of force in nature is just as eternal and inalterable as
the quantity of matter. Expressed in this form, I have named the general law 'The
Principle of Conservation of Force'." 314.
Clausius is clearly and explicitly praised for the first expression of the
second principle, a principle that does not contradict the law of conservation of
force :
"Only when heat passes from a warmer to a colder body, and even then
only partially, can it be converted into mechanical work" 315.
After giving credit to Carnot and W.Thomson, to the latter also for the
problem of thermal death, Helmholtz abandons mathematical-mechanical
developments and instead of giving "a glance at the narrow laboratory of the
physicist" gives " a glance at the wide heaven above us, the clouds, the rivers, the
woods and the living beings around us" 316.
An extraordinary series of applications of the great law now takes
place, ranging from a reassessment of the Kant-Laplace hypothesis (with a
calculation of the heat produced by the assumed condensation of the bodies of
our system from scattered nebulous matter) to the evaluation of the heat produced
by the speed of the meteors, and to the comparison of the heat coming to the
surface of the earth from within, with that reaching the earth from the sun. The
conservation of force is then applied to organic bodies : we can calculate from
the mass of the consumed nutritive material how much heat, or its equivalent
work, is generated in an animal body; the influence of the sun explains why the
combination of the animal and vegetable organic realms does not produce
perpetual motion. There is thus a specific sense in which we can all consider
ourselves to be "as the great monarch of China, sons of the sun"! 317 The ebb and
flow of tides are explained too, through the combined action of the sun and the
moon. The motions of the tides, as already done by Mayer 318, are connected to
the law of conservation of force: they "produce friction, all friction destroys vis
viva, and the loss in this case can only affect the vis viva of the planetary
system." Finally the thermal death of the sun is discussed.
314 Helmholtz "Interaction" p.501
315 Helmholtz "Interaction" p.502
316 Helmholtz "Interaction" p.503
317 Helmholtz "Interaction" p.511
318 Helmholtz "Interaction" p.512