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DR. PROUT ON CHEMISTRY. 
terial grounds, and launch into the wide ocean of metaphysics, 
all is fancy and hypothesis; and nervous power, nervous irrita¬ 
bility, morbid and healthy, nervous sympathy, and a host of 
other terms of similar character, are, for the most part, mere words 
to which no two individuals attach exactly the same meaning, 
and which often have no meaning at all, but are nothing more nor 
less than a technical gloss to cover our ignorance. 
Now between these two extremes—the purely mechanical on 
the one hand, and the purely metaphysical on the other—there 
lies an immense chasm, in which is included by far the greater 
proportion of those important changes which take place in organ¬ 
ized beings. The nature of these changes, and of the laws by 
which they are conducted, have probably no exact prototype 
among those of inanimate bodies; but they are obviously most 
nearly allied to the changes and laws of common chemistry: ac¬ 
cordingly, chemistry, from its earliest dawn as a science, has been 
eagerly pressed into the service of the physiologist; and chemists 
of the first talent have laboured most assiduously, and exerted all 
their powers, to further his views, but hitherto without the ex¬ 
pected results ; and it must be fairly confessed, that physiology 
and pathology have derived much less advantage from this branch 
of knowledge than might have been expected. The reason of 
this failure, no doubt, is to be ascribed, in part, to the difficulty of 
the subject; but it is no less true, that it has been rendered the 
more signal by the imperfect manner in which the science has 
been applied. While chemistry was little more than a branch of 
natural philosophy, and confined to those who had not studied 
physiology, what could be expected from it? The utmost that a 
mere chemist could be supposed to effect would be, to examine an 
organized body as he would a mineral one, and tell you it was 
soluble is this, and precipitated by that, and so on; all very im¬ 
portant information in its way, but unfortunately of a description 
totally useless to the physiologist, and calculated only to disgust 
him. Another fatal rock on which those have split who have at¬ 
tempted to apply chemistry to physiology and pathology has 
been, the hasty assumption, that what they found by experiment 
to be wanting or otherwise deranged in the animal economy was 
the cause of particular diseases, and that these diseases were 
to be remedied by supplying or adjusting, artificially, the princi¬ 
ple in error. Now, in general, nothing can be more absurd than 
such reasoning as this ; and the physiologist or pathologist who 
adopts facts, and reasons upon them in this manner, as a 
mere chemist would do, will be almost certainly led astray; and 
if he be given to castle-building, and construct his airy fabric on 
such a foundation, he will sooner or later have the mortification of 
