354 
DR. PHILIP ON THE POWERS OF LIFE. 
into a healthy chyme, the formation of which, it appears from direct experiments, 
depends on the healthy state of the influence supplied by the brain and spinal 
marrow*. In like manner, the healthy action of the intestines, as appears from a 
thousand observations, can only be maintained when their healthy stimulant has 
been duly prepared by the chemical processes which take place in the duodenum ; 
which also depend on the influence supplied by the brain and spinal marrow. It 
is evident that all the other functions just enumerated are of a chemical nature. 
It thus appears that all the nervous functions are chemical processes, and conse- 
quently that there may be an expectation of finding an agent in inanimate nature 
capable of them. 
It was found that in proportion as the nervous influence, properly so called, is 
withdrawn, all these processes fail. It is evident therefore that on this influence the 
changes observed depend. Whatever therefore that influence may be, all its functions 
in their general nature are identical with the effects of the chemical agent, whatever 
that agent may be, which operates in inanimate nature. This step therefore appeared 
to be gained. Further reasoning however was unnecessary, because it was not diffi- 
cult to submit the question to the test of direct experiment. 
I was thus led to consider what power of inanimate nature it was most probable 
might be successfully substituted for the nervous influence. 
An important point had been ascertained. It had been found that of all the powers 
of inanimate nature, voltaic electricity is most capable of the excitement of the mus- 
cular fibre, that is, of one of the functions of the nervous influence. This indeed went 
but a short way towards establishing the identity of the two powers, so many other sti- 
mulants being capable of exciting that fibre. It is not to be overlooked, however, that 
feeble as this argument is towards proving the identity of the nervous influence and 
voltaic electricity, it is powerful respecting the general nature of that influence ; be- 
cause on the supposition of the nervous influence being a vital power properly so 
called, we have here a vital power possessing a property in common with a thousand 
inanimate agents. Is there any unequivocal instance in which any of the properties 
of a vital principle, properly so called, is not essentially different from those of any of 
the principles of inanimate nature ? On the whole, the property in question was 
sufficient to suggest the trial how far voltaic electricity is capable of the other func- 
tions of the nervous influence. 
No hope of success of course could be entertained unless the artificial agent were 
employed under the same circumstances, under which the nervous influence operates ; 
that is, while the structure of the organs is entire, and their vital properties unim- 
paired. 
Under such circumstances I substituted it for the nervous influence in the various 
functions of secretion and assimilation with success. It was admitted by those who 
* Philosophical Transactions for 1815 and 1822, and Inquiry into the Laws of the Vital Functions, Part II. 
