HIS ESSAY ON THE SKIN AND LUNGS.
"It is madness and a contradiction to expect that things which were never yet performed should be effected, except by means hitherto untried."—Bacon, Nov. Org. Aph. 6.
When we consider the object which the distinguished Author had in view, in the immortal Work whence we have taken the foregoing simple but instructive aphorism, we cannot but perceive how highly suggestive it is to those engaged in scientific researches, or how necessary to be borne in mind by those who are really aware of the present state of Medicine and Surgery, and desirous of seeing them become a definite science. Nor does it appear inappropriate to the consideration of Abernethy's experimental inquiries into the functions of the skin and lungs. An extended investigation—of which his paper on these subjects contains an excellent type, and is in part a practical application—would be a great step towards the creation of a real science, and would certainly fall within the "means untried" of Lord Bacon.
Although the latter part of the last century, and the first half of the present, have been very remarkable for the number of distinguished men who have flourished during that period, in almost every branch of knowledge; yet neither the bar nor the senate, neither literature nor any of the sciences, can boast of greater men, nor lay claim to more positive improvement, than Chemistry.
If we only consider that interval between the discovery of oxygen by Priestley, in 1774, and the conclusion of Sir Humphrey Davy's labours, Chemistry almost seems like a new science; and it continues to advance with such rapidity, and is daily opening out so many new questions, that the most accomplished chemist of one year is never sure how much he may have to learn the next; nor, unless he reasons with great caution, how much he may have to unlearn.
To a physiologist, who requires assistance from all branches of science, Chemistry must always be an interesting study. When we lay aside all speculations as to what is the abstract nature of Life, and study that which is the proper object of philosophy—that to which it seems the faculties of man are limited—namely, the laws in obedience to which the phenomena in nature occur; and apply the knowledge thus obtained to the occurrences which take place in the human body; we soon discover that, whatever the abstraction "Life" may be, we live proximately, in virtue of certain changes in various forms of matter; as food, air, the various constituents of our bodies, &c.; and that these consist of multiplied separations and rearrangements of their respective elements, which it is the special province of Chemistry to examine.
If we investigate the changes of the living, or the structure of the dead, with these objects,—we shall be in no danger of perverting Chemistry to purposes to which it is inapplicable. When, however, we proceed a step further, and seek to give a chemical expression to various uses and relations of different parts of the body, the greatest caution is required.
In the first place, in a machinery which is a practical application of a great many sciences, it is to the last degree improbable that they can be expressed by any one.
Again, to estimate the true meaning—the physiological interpretation of many changes which might be in their proximate sense chemical,—a greater familiarity with the phenomena of disease is necessary than usually falls within the inquiries of the most scientific chemist.
To a person acquainted only with the ordinary phenomena of health, or who is not even something also of a philosophical pathologist, Chemistry is for ever suggesting tempting analogies, which are constantly tending to mislead him to conclusions on insufficient data; and to examine and rest too much on the chemical facts deducible from one or other function, without sufficiently attending to the physiological relations of that function with all others.