Popular Science Monthly/Volume 10/April 1877/Correspondence

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CORRESPONDENCE.
 

THE NATURE AND CAUSE OF FERMENTATION AND PUTREFACTION.

To the Editor of the Popular Science Monthly.

I HAVE read with no ordinary interest the lecture by Prof. Tyndall, published in your issue of December, upon the subject of "Fermentation and its Bearings upon the Phenomena of Disease;" and I desire, with your permission, to submit some points suggested to my mind upon which, according to my own conception, there remains some doubt, and which I should like to see explained. It is not my intention to dwell upon the general subject of the nature and causes of fermentation, but merely to touch upon it, confining myself rather to the question of the causes of putrefaction.

In fermentation and the production of alcohol, the presence of bacteria seems to be constant. Prof. Tyndall holds that the changes resulting in the formation of beer and the production of alcohol are due to the action of these microscopic germs, which, seizing upon the grain, or fruit, elaborate the spirit. Now, it does not seem to me perfectly clear that the changes which take place in the fruit may not be purely chemical, and that a portion of the component elements of the fruit, not requisite to form the chemical combination of alcohol, becomes a suitable soil in which the air-germs can take root and grow. It is a question of cause and effect.

Again, a certain amount of moisture is necessary to the production of mould. It may be asked: Is it quite certain that the moisture is not the agent of a chemical decomposition, and that the growth of mould is due to the deposit of seed in soil furnished by this decomposition? May it not be that a dry and cold atmosphere prevents or retards chemical decomposition in devitalized organic matter, while heat and moisture cause or facilitate it? Why should we disregard the chemical forces in the decomposition of organic matter deprived of vitality? Or, does Prof. Tyndall wish us to regard all organic matter as possessed of vitality until it is decomposed? Indeed, he says: "Cherries, apples, peaches, etc., are composed of cells, each of which is a living unit;" and "the living cells of fruit can absorb oxygen and breathe out carbonic acid, exactly like the living cells of the leaven of beer." We know that the seed of fruit possesses vitality; but is it proof of vitality in the cells, that certain changes take place between the constituents of the cells and the external air, and that other changes take place when the fruit is excluded from the air? Granting it is, then shall we say that all vegetable products, although long since uprooted but undecomposed, are possessed of life? Are the cells which compose the well-worn oak-beams of the few remaining wooden walls of Old England still endowed with vitality, and constantly engaged in a struggle for life with the low forms of animated Nature? Then, if this be conceded, might we not assume that fructification of germs is likewise essential to the decomposition of minerals? If the decay of an old boot is dependent upon the growth of mould, may we not suppose that the rusting of an old axe is due to similar influences; and that the erosion of rock, which in time forms abundant soil for vegetation, is the work of microscopic germs, although commonly supposed to be due to physical forces?

Prof. Tyndall says that "some of the numberless air-germs produce acidity, some putrefaction." But when acidity takes place rapidly, as in a frozen apple just thawed, and with an unbroken skin, are we still to regard it as the result of bacteria? With regard to putrefaction, Prof. Tyndall cites a number of experiments with beef-tea. Now, to make these perfectly satisfactory, it seems to me that the fluid ought to be exposed to not a limited quantity of pure air, but a free change of air from which all motes had been removed.

I now come to the subject of putrefaction in connection with the living body, and the antiseptic treatment of wounds as taught by Prof. Lister, of Edinburgh. Prof. Tyndall says that he has obtained "a specific against putrefaction and all its deadly consequences." This statement might lead the public to believe that the teachings of Prof. Lister were generally accepted by the medical profession. Such, however, is by no means the case, notwithstanding his practice has been thoroughly tried in most if not all the principal hospitals of Europe and America. While a certain number have adopted his method, the majority have rejected it, with the conviction that other treatment less troublesome is quite as, if not more, successful. That Prof. Lister's theories and practice are not believed in by the representative surgeons of the United States, was clearly demonstrated at the late International Medical Congress, at Philadelphia. Prof. Lister was chairman of the surgical section, and he was courteously allowed all the time and opportunity he desired, which was a good deal, to fully explain his views. But, after all, the section refused to indorse his mode of treating wounds. The presence of germs in the air was not denied; the views of Pasteur were not disputed; but the question was, Have these theories, facts if you please, any necessary connection with putrefaction? The question was and is: Is it true, or not true, that putrefaction cannot take place without the presence of air-gems? Is it true that animal organic matter, when deprived of vitality, will remain undecomposed for an unlimited time unless bacteria seize upon it; or will it not, by a purely chemical process, decompose? Decomposing organic matter, we know by daily observation, is the abode of low, degraded animal life, and the soil in which low forms of vegetable life take root and grow; but are we to regard this as the cause or the result of putrefaction? If it be admitted that putrefaction may, under any circumstances, in the absolute absence of bacteria, take place as a chemical process, is it not begging the question to assert that their presence is ever necessary? Every surgeon knows that putrefaction does often take place in the body beneath an impervious skin. This fact was accounted for by Prof. John T. Hodgen, of the St. Louis Medical College, who was the surgical reporter at the recent congress, upon the subject of antiseptic surgery, on the supposition that the bacteria reached the place of putrefaction through the lungs, or stomach, and the blood. He also declared that bacteria had been found in wounds beneath Prof. Lister's most elaborate and carefully-prepared dressings; and that they must have found their way there through the blood. But Prof. Lister took occasion to repudiate this doctrine. He did not believe the germs arrived at the wound by way of the blood-vessels; and we can understand why he should reject this theory. The writer of this communication then pointed out the uselessness of Prof. Lister's antiseptic dressing externally, if bacteria could enter by another way. Prof. Lister not only denied this theory, but admitted that putrefaction did sometimes take place independently of bacteria as a chemical process. The writer then submitted, and it is submitted now, that if putrefaction ever takes place without the influence of bacteria, it is impossible to prove that it, in any case, depends upon their presence.

It is no uncommon experience of surgeons to see wounds heal rapidly without putrefaction, although no steps are taken to place a barrier to the entrance of air-germs, or to destroy those which may have lodged in the part. Undoubtedly the air is, sometimes, especially in badly-ventilated hospitals, loaded with germs of a specific and poisonous nature, which will contaminate any wound, as the poison of erysipelas, but that common unadulterated air is inhabited by organisms whose existence and operation are essential for putrefaction, remains unproved. The value of carbolic acid and similar agents is generally acknowledged by the medical profession. They are in constant use, but not with the view of destroying germs. They are found to possess the property of arresting or preventing putrefactive chemical decomposition—just as common salt has in preserving meat—and hence their usefulness in the treatment of wounds.

When Prof. Tyndall "passes the bounds of surgery and enters the domain of epidemic disease," and points out the analogy between contagium and fermentation, he gives utterance to views long held by the medical profession. That small-pox, scarlet fever, etc., are developed in the system by "indefinite self-multiplication of germs (zymosis) introduced from without," is a commonly-accepted doctrine.

In support of the statement that Prof. Lister's antiseptic method is not regarded as essential to the successful treatment of wounds, one fact may be given, although more might be furnished. Prof. Spencer, who occupies the chair of surgery in the Edinburgh University, and who is therefore a colleague of Prof. Lister's, and likewise the author of a highly-esteemed work on surgery, continues to treat wounds without reference to Lister's theories, with results quite as satisfactory as any claimed by Prof. Lister.William Canniff, M. D.

Toronto, December 12, 1876.

 

 
INSECTS AND FLOWERS IN COLORADO.

To the Editor of the Popular Science Monthly.

Allow me to express my thanks to Prof. Gray, and Mr. Putnam, in so kindly furnishing the facts I asked for in regard to the insects of Colorado. Since my inquiry was written, Prof. Gray has defined his position in the January number of the American Agriculturist. He does not contend for the general necessity of cross-fertilization as Lubbock, Wallace, and others have done, but simply that an occasional cross is beneficial. When flowers are not visited by insects, they generally self-fertilize. "'Cross-fertilize if you can, self-fertilize if you must,' is Nature's golden rule for flowers." Of course this narrows the question to the benefits of an occasional cross, and renders much that I have written no longer of account. Of this character is this question of the quantity of insects in Colorado. If plants can "generally" fertilize themselves without insect aid, simply preferring cross-fertilization through insect agency when they can get it, the abundance or partial absence of insects there is of little consequence in the argument.

The question being purely entomological, and no longer of importance to the botanist, I should feel sorry for having put Mr. Putnam to the trouble of writing his letter, only that I know facts are always welcome to the lover of science, though they may have no immediate bearing on questions under discussion.Thomas Meehan.

Germantown, Pa., February 22, 1877.

 

 
THE MATHEMATICAL CONTROVERSY.

To the Editor of the Popular Science Monthly.

Sir: You will doubtless be gratified to find that the premise upon which you have rested a charge of disingenuousness against a gentleman no longer living is mistaken. The case is this: You find that the negatively-quantitative geometry of Spencer's first edition of his "Classification of the Sciences" must have been that branch of mathematics which has grown up under the name of "Descriptive Geometry;" and you find the late Mr. Chauncey Wright disingenuous in representing that' Spencer had reference to those technical methods of geometrical construction to which engineers apply the name. But Wright, like you, understood Spencer to refer to Monge's descriptive geometry; and it was just that which he characterized as a mathematical art having no place among the abstract sciences.

Permit me to add that I used to talk with Wright, daily, while he was writing the article in which this matter is discussed; and I declare that nothing could less describe his method than to say that he "was hunting through Spencer's various books in search of flaws." On the contrary, no critic ever studied his author more conscientiously; and very few have succeeded as well as he did in comprehending thought remote from the channel of their own. The present case illustrates this, for Wright seemed to detect that Spencer had two very different things confounded together in his mind, viz., descriptive geometry and positional geometry. The second edition of Spencer's book makes it pretty clear that this is so; for some of his warm disciples maintain that he still means the former, while to the mathematician his present words describe with tolerable accuracy the latter.

No doubt, Wright greatly under-estimated the importance of Herbert Spencer's philosophy. This was natural, because he found in Spencer's fundamental doctrine of the universality of evolution a proposition radically opposed to his own theory that there is only an ebb and flow, in this respect, and no unending progress. But such sharp antagonism only serves to make his criticisms all the more instructive. Whatever there may be of extravagance in the claims which are made for Spencer will be overthrown in the course of the discussion which is sure to go on, and which he himself would be among the very last of men to deprecate. It would be strange, indeed, if it were to turn out that an encyclopedic system of philosophy had been produced, so perfect in its details as to satisfy specialists. But disputation clears the philosophic air, and can only serve to bring into the light and to sharpen the outline of all that is to abide in Spencer's system. In this point of view, I cannot agree with you that Mr. Spencer's distinguished candor has done him any harm, or has postponed the knowledge of the truth for which he is striving.

Mr. Wright occupied a position opposed to that of most modern mathematicians, in maintaining that positional geometry is not quantitative. This, however, is not a question of mathematics, but of logic: and it goes very deep into the theory of logic, too. But, while it does not concern the "mathematical expert," as such, one does not perceive that Mr. Spencer has proved himself so supremely the master of the philosophy of mathematics that we need be greatly anxious lest Mr. Cayley should have ventured to express himself on the subject, without proper study of what Spencer has said.

You well say that we here "encounter a difficulty which always arises when knowledge outgrows old definitions." Prof. Peirce, in his "Linear Associative Algebra," offers a definition of mathematics, the acceptance of which would not necessarily involve any decision of the question whether that geometry which is not metrical is quantitative or not. Although linear associative algebra is certainly not popular science, perhaps you will find his remarks of sufficient general interest for insertion. He says:

"Mathematics is the science which draws necessary conclusions.

"This definition of mathematics is wider than that which is ordinarily given, and by which its range is limited to quantitative research. The ordinary definition, like those of other sciences, is objective; whereas this is subjective. Recent investigations, of which quaternions is the most noteworthy instance, make it manifest that the old definition is too restricted. The sphere of mathematics is here extended, in accordance with the derivation of its name, to all demonstrative research; so as to include all knowledge strictly capable of dogmatic teaching. Mathematics is not the discoverer of laws, for it is not induction; neither is it the framer of theories, for it is not hypothesis; but it is the judge over both, and it is the arbiter to which either must refer its claims; and neither law can rule, nor theory explain, without the sanction of mathematics. It deduces from a law all its consequences, and develops them into the suitable form for comparison with observation; and thereby measures the strength of the argument from observation in favor of a proposed law, or of a proposed form of application of a law.

"Mathematics, under this definition, belongs to every inquiry, moral as well as physical. Even the rules of logic, by which it is rigidly bound, could not be deduced without its aid. The laws of argument admit of simple statement; but they must be curiously transposed before they can be applied to the living speech and verified by observation. In its pure and simple form, the syllogism cannot be directly compared with all experience, or it would not have required an Aristotle to discover it. It must be transmuted into all the possible shapes in which reasoning loves to clothe itself. The transmutation is the mathematical process in the establishment of the law. Of some sciences it is so large a portion that they have been quite abandoned to the mathematician, perhaps not altogether to the advantage of philosophy. Such is the case with geometry and analytic mechanics. But in many other sciences, as in all those of mental philosophy and most of the branches of natural history, the deductions are so immediate, and of such simple construction, that it is of no practical value to separate the mathematical portion and subject it to isolated discussion.

"The branches of mathematics are as various as the sciences to which they belong, and each subject of physical inquiry has its appropriate mathematics. In every form of material manifestation there is a corresponding form of human thought, so that the human mind is as wide in its range of thought as the physical universe in which it thinks. The two are wonderfully matched. But where there is a great diversity of physical appearance, there is often a close resemblance in the processes of deduction. It is important, therefore, to separate the intellectual work from the external form. Symbols must be adopted which may serve for the embodiment of forms of argument, without being trammeled by the conditions of external representation or special interpretation. The words of common language are usually unfit for this purpose, so that other symbols must be adopted, and mathematics treated by such symbols is called algebra. Algebra is, then, formal mathematics." I am, etc.,C. S. P.

 

We cheerfully give place to the foregoing, prompted as it is by the generous desire of the writer to speak for one who can no longer speak for himself. Yet it hardly appears how our correspondent has much improved his friend's case. He objects, on the strength of intimate acquaintance with Mr. Wright and the spirit of his work, to our remark that he "was hunting through Spencer's various books in search of flaws." We certainly are not entitled to speak of Mr. Wright's motives, any further than they can be fairly gathered from his writings. No fair-minded person, acquainted with Herbert Spencer's labors, can deny that Mr. Wright's criticism upon him, in the North American Review of 1865, was a very prejudiced piece of work. C. S. P. admits that he greatly under-estimated the importance of Spencer's philosophy, which he accounts for by the natural bias of one who entertains rival views in the same field. Yet the article was far less a judgment of the philosophy, of which but a single volume had then appeared, than an estimate, gathered from an examination of Spencer's various productions, of his competency to produce a philosophy. He undertook to measure the man, and, as we now understand, with a predisposition to underrate him. He, therefore, could not have approached his works in an impartial or judicial temper, but rather in a state of feeling which interested him in their defects. At any rate, if he was not in quest of flaws, it is difficult to see how it was that he found nothing else. Six years before Mr. Wright wrote, and before Mr. Spencer had published a word of his philosophy, several of the ablest men in England joined in an appeal to the Government to secure for him a position of trust, on the ground that he was eminently the man to do a great and special work for the advancement and organization of knowledge that should be a national honor; and now, a dozen years after Mr. Wright wrote, the sixth volume of his philosophical system is awaited with eagerness by the leading minds of the foremost countries in the world. That is to say, he is doing the work that English philosophers predicted long ago (on the basis of what he had already published) that he would do. His works must, therefore, have had some excellences, some elements of strength, which it was the duty of candid criticism to recognize. But Mr. Wright seems to have seen in them little except evidences of "ignorance," "incompetency," "confusion," "inconsistency," "perverted terminology," "fanciful discriminations," and, massing together these faults, he winds up his article with the inference of Spencer's "incompetency for the further development of his encyclopedic abstractions." This looks very much to us like "picking flaws," under the inspiration of a not very creditable purpose. As to the special case there can be no doubt that Mr. Wright made a charge of ignorance against Mr. Spencer, founded on misrepresentation. He says that in his mathematical classification Spencer "has given a prominence to descriptive geometry which might be regarded as arising from the partiality of the civil engineer for a branch of his own art, were it not that he says, 'I was ignorant of the existence of this, as a separate division of mathematics, until it was described to me by Mr. Hirst.'" The insinuation is that Spencer, though educated as a civil engineer, was unacquainted with the branch of mathematical art that is especially familiar to engineers. That this imputation was groundless may be proved by referring to the Civil Engineer and Architects' Journal for 1839-40, where will be found conclusive evidence of Mr. Spencer's early and thorough familiarity with the subject. Among other original papers in the field of descriptive geometry there published will be found a beautiful original theorem which dates back to the time when Spencer was but seventeen. He was not, then, so ignorant as Mr. Wright intimated, and certainly not so grossly ignorant as to confound a practical art with an abstract science, as erroneously represented by his critic. Although the arts grow into the sciences, so that both often pass under the same name, it requires no great discrimination to separate them; and if a question could arise as to which is meant, the character of the discussion would sufficiently determine it. Mr. Wright was no more justified in assuming that, by "Descriptive Geometry," as he was dealing with it, Mr. Spencer meant "certain methods of geometric construction, useful in engineering," than that by "geometry" he meant the art of earth-measuring instead of the science, or by "chemistry" the art of manufacturing paints and dyes, instead of its scientific principles. By the term "descriptive geometry," employed, as it was, in its scientific significance, Mr. Spencer did not mean Monge's "Géometrie Descriptive" of a hundred years ago, in which theorems and their applications to drawing were mingled together, but he meant the branch of mathematical science which has since grown up under this title, while omitting all mention of the practice that gave it the name of Descriptive Geometry, and for which the title Geometry of Position is now substituted. As Mr. Wright suggests the alternative that Mr. Spencer may have meant something else than what he imputed to him as the basis of a charge of ignorance, it is fair to infer that he did not know what he meant; and if he had not been animated by a predisposition to make out a bad case, he would have abstained from taking up the point, or would have dealt with it in a different spirit. We desire to do no injustice to the memory of Mr. Wright, but, as his works are now brought forward in a collective and permanent form, they are the proper objects of criticism, and we have commented upon one part of them, solely in what we consider the interest of truth.