1864.] Carpenter on Correlation of Physical and Vital Forces. 77 
generation ; that, namely, which, whilst fully accepting the logical 
definition of the cause of any phenomenon, as ‘‘ the antecedent, or 
the concurrence of antecedents on which it is invariably and uncon- 
ditionally consequent” (Mill), draws a distinction between the dyna- 
mical and the material conditions; the former supplying the power 
which does the work, whilst the latter affords the instrumental means 
through which that power operates. Thus, if we inspect a Cotton- 
factory in full action, we find it to contain a vast number of machines, 
many of them but repetitions of one another, but many, too, present- 
ing the most marked diversities in construction, in operation, and in 
resultant products. We see, for example, that one is supplied with 
the raw material, which it cleans and dresses ; that another receives the 
cotton thus prepared, and “cards” it so as to lay its fibres in such an 
arrangement as may admit of its beimg spun; that another series, 
taking up the product supplied by the carding machine, twists and 
draws it out into threads of various degrees of fineness; and that this 
thread, carried into a fourth set of machines, is woven into a fabric 
which may be either plain, or variously figured, according to the con- 
struction of the loom. In every one of these dissimilar operations, 
the force which is immediately concerned in bringing about the result, 
is one and the same; and the variety of its products is dependent 
solely on the diversity of the material instruments through which it 
operates. Yet these arrangements, however skilfully devised, are 
utterly valueless without the force which brings them into play.* All 
the elaborate mechanism, the triumph of human ingenuity in devising, 
and of skill in constructing, is as powerless as a corpse, without the vis 
viva which alone can animate it. The giant stroke of the steam-engine, 
or the majestic revolution of the water-wheel, gives the required im- 
pulse ; and the vast apparatus which was the moment previously in a 
state of death-like inactivity, 1s aroused to all the energy of its 
wondrous life,—every part of its complex organization taking upon 
itself its peculiar mode of activity, and evolving its own special product, 
in virtue of the share it receives of the one general force distributed 
through the entire aggregate of machinery. 
But if we carry back our investigation a stage further, and inquire 
into the origin of the force supplied by the steam-engine or the 
water-wheel, we soon meet with a new and most significant fact. At 
our first stage, it is true, we find only the same mechanical force 
acting through a different kind of instrumentality ; the strokes of the 
piston of the steam-engine being dependent upon the elastic force of 
the vapour of water, whilst the revolution of the water-wheel is main- 
tained by the downward impetus of water en masse. But to what 
antecedent dynamical agency can we trace these forces? That agency, 
in each case, is Heat; a force altogether dissimilar in its ordinary 
manifestations to the force which produces sensible motion, yet capable 
of being in turn converted into it and generated by it. For it is 
from the Heat applied beneath the boiler of the steam-engine, that the 
non-elastic liquid contained in it derives all that potency as elastic 
* In going through a manufacturing town, I have often been struck with the 
announcements of ‘ Power to Let.” 
