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proceeded at once to determine the velocity for example, these critics of Dr. Audsley exof the prong's travel by this new method of measurement from the time it is first bowed to the close of its audible swings (four minutes), with the result as stated and given in the MICROCOSM.

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citedly declare at the close of his recent lecture that he had evidently misunderstood the authors from whom he had quoted, and that the "swiftly advancing" of Tyndall and the "very much faster" of Helmholtz, instead of meaning a swift travel of the prong, only meant " a very much greater frequency of vibration" than that of the pendulum of a clock!

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Plainly these critics had to say something in reply to this "swiftly advancing argument or at once abandon their theory, and this ridiculous assault upon Tyndall and Helmholtz as incapable of understanding the true meaning of words was manifestly the last ditch of the wave-theory.

How Tyndall, Helmholtz, Mayer, Rood, Sir William Thomson and Lord Rayleigh must have felt can only be imagined when they learned for the first time in their lives from this demonstration, that instead of the prong "swiftly advancing" and traveling very much faster" than a pendulum, it actually can be heard sounding when traveling 25,000 times slower than the hour-hand of a clock ! They must have seen from this astounding measurement that the entire air-wave system of sound-propagation had vanished into some- But as Dr. Audsley had not time to answer thing thinner than Prof. Tyndall's scientific them, we shall now bring them to a public smoke of brown paper. Yet not one of these trial that will settle them "very much writers has had the philosophical manhood faster" than they then fancied possible. To either to acknowledge the fact, or to attempt do this let them try to analyze the two to overturn our demonstration, for the reason passages quoted at the commencement of this that any open attempt, as they well know, to article in the light of their shallow interpretaquestion the substantial correctness of that tion, and see if they can make "swiftly measurement or defend the wave-theory from advancing" by Tyndall and "very much its crushing effect, would be to inaugurate a faster" by Helmholtz mean a "greater logical cataclysm of discussion that would frequency of vibration" than that of the sweep their acoustical text-books out of exist-pendulum? What sense, for example, would Hence silence to them was literally there have been in Tyndall's lecture had he golden. Notwithstanding their silence, how-meant to teach as these critics insist: "Imever, it is well known that the revelation thus agine one of the prongs of the vibrating fork" made in regard to the almost infinitely slow frequently advancing; "it compresses the air travel of the tuning-fork's prongs, hurled con- immediately in front of it, and when it resternation into the ranks of all thoughtful treats" from frequently advancing "it leaves physicists from one end of this continent to a partial vacuum behind” this great frequency the other. of vibration, the process being repeated at every subsequent” frequency of "advance and retreat,” etc.!

ence.

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It passes comprehension that learned critics do not know the difference between "swiftly advancing" and "frequently vibrating," especially when Prof. Tyndall immediately adds retreating and leaving a partial vacuum as distinct from the "swiftly advancing” which condenses the air. But almost anything may be expected from men who can accept the

But silent and sullen as have been the English and German physicists on this startling announcement, they have at last been forced, nolens volens, before the glaring foot-lights of popular investigation. The scathing criticisms of the wave-theory as set forth in Dr. Audsley's lectures before appreciative London audiences, have succeeded in calling out replies from numerous advocates of that theory at the conclusions of his lectures, with all sorts of imaginable attempts at evading | wave-theory of sound without being able to the destructive force of his arguments. They detect any of its glaring absurdities. now seem to see for the first time that some- Then next let these critics try to prove thing desperate has to be done if their un- Helmholtz a similar dunce in the use of landulatory cause is not to be ingloriously lost. guage by giving a similar interpretation to his. To let the charge pass unnoticed, that all the words. Thus: "The pendulum swings from great physicists of the world up to 1877, | right to left with a uniform motion. near when the "Problem of Human Life" first to either end it moves slowly," that is, with inappeared, were ignorant of the fact that the frequency of vibration, "and in the middle prong of a tuning-fork produces sound when fast," or with great frequency of vibration. traveling a million times slower than a clock-"Among sonorous bodies which move in the pendulum, they now see would be to stamp same way but very much faster," that is, with with doubt and unreliability all the works on very much greater frequency of vibration 66 we acoustical science up to that date. Hence, may mention tuning-forks!"

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The result of this simple analysis of the words of these two highest living authorities on sound forever settles the question that, up to the revelation made in the "Problem of Human Life" and the MICROCOSM, the wavetheory was based upon the mistaken idea of physicists that the prong and string must necessarily travel swiftly in order to produce the "condensations" essential to sound-waves. As this essential phase of the theory is here incontinently wiped out, all rational excuse for further teaching that theory has ceased. Will professors of physical science in our colleges have the manliness to acknowledge the force of this reasoning?

MATTER AND FORCE.
BY THE ASSOCIATE EDITOR.

It is seldom in the course of any investigation that we find two elements which are so closely subjoined and connected with each other, yet so absolutely different in their elemental bases, and so completely independent of each other for existence as those mentioned in the caption of this article.

It is a universally admitted scientific fact that the existence of the material world in its tangible shape is due to the action of force, and that the peculiar material formations which are manifested are given their particular characteristics by the action of the different forms of force. It is not the purpose of this article to dispute this fact, but rather to defend it. Our purpose being more to point out a constitutional difference between matter and force, and to show that while the two principles are joined together in universal and almost infinite relationship, nevertheless as pure matter and force they are not to be confounded, nor are they to be considered as primarily dependent in any sense upon each other.

emanation from force-is at once practically to deny the existence of the immaterial realm, dition of material existence, from which matmaking it instead an infinitely attenuated conter is simply the condensation, resultant from the continuous action during ages of time; while, on the other hand, to make force dewould be to strike from under Substantialism pendent for its existence upon material action the very corner stone upon which its superstructure has been reared.

From substantialists, therefore, this doctrine of a distinct line of demarkation between matter and force as substantial and independent elements in their originally crude states, may expect no semblance of disapproval, but from the generally accepted schools of scientific and philosophical teaching, whose whole systems have been founded and carried out on the supposed dependence of force upon the previous existence of matter and contrary wise, such a claim can hardly expect to be favored with even a suspicion of mercy.

Between two otherwise antagonistic schools of philosophers, there seems to be a harmony in that they regard the phenomena of matter and force as entirely dependent one upon the other for its existence, the magnitude of their dispute when reduced to its essence entering apparently upon the superior claims of either the matter or force phenomenon to prior existence.

The undulatory scientists, to whom belong Tyndall and Helmholtz, regard force universally to be simply the resultant of the molecular motions of matter which, as has been shown, had no existence before the material motion began, and can have none when the motion ceases; while, on the other hand, we have the idealists numbering among their school Hume and Spinoza, who, for their dictum, declare that matter has no reality, relegating it to a similar state of dependence upon force by their teaching that it exists only in the sensuous perceptions and conceptions, which sensuous actions are universally admitted to be simply properties of mental force.

While these two elements in their interlock- If both these schools of teaching be correct ing alliance represent the complete and eternal the inference is unavoidable, that the universe constitution of the universe, and by their is a myth, an empty state of nothingness, for combination or coalition are each endowed with the properties or characteristics which give them their differing molecular structures, and consequent usefulness or uselessness in the economy of natural requirements, yet were they by any means separated from each other neither would be annihilated or cease to exist, but would simply be relegated back to its primeval condition of crude matter or crude force.

if the position of the idealist be true that matter is dependent for its existence upon the activity of mental force, then according to the equal truth of the position of Tyndall, Helmholtz, Mayer and all other authorities on Natural Science, there can be no such thing as force, since force of all kind is dependent upon the previous presence and agitation of material molecules. When brought to their fundamentals either of these positions is as corThus, while there is an intimate relationship rect as the other, the difference between them and seeming interdependence between matter being only caused by whether they take the and force, the dependence is only apparent, as matter or force as the starting point of physical the two elements being by nature different, are being. So much has been said in the past volpossessed of the virtue of separate self-exist-umes of this journal proving the absurdity of ence. One is material, the other is immaterial, both these positions that we will not here ocand while the material is dependent for its vari-cupy space by a repetition, but will go directly ous phases and ramifications in the tangible to the effects which this principle of a separate universe upon the immaterial, and the immaterial dependent for its opportunities of manifestation upon the material, yet matter per se is not the resultant of force action, nor is force the resultant of any form of material action.

It is clear that this must be the position of the Substantial Philosophy with regard to these entities: for, to consider matter to be entirely a secondary condition of the universe-but an

and distinct existence of the material and immaterial departments of the universe will have upon the present theories of the natural forces.

There is no good reason that we can see on the basis of consideration that there are in the constitution of the universe two factors, matter and force, equally independent of each other, equally important and equally extensive, why

in their peculiar realms of existence they should not have equally the same conditions, the same manifestation of properties, and the same general reign of laws differing only in being suitable to their particular requirements. There is without doubt a structure of particles in the constitution of force as well as in matter, and as in dealing with material substances such expressions as weight, thickness, transparency, etc., etc., are simply relative terms which convey to the mind the differences between the various forms and conditions of material existence, so undoubtedly in the immaterial realm there are analogous relative differences, and thus the consequent opportunities for comparisons, which we believe upon a better understanding of the conditions prevalent in this important part of God's domain will reveal to us properties and qualities which will vie with the material portion in number, variety and adequacy in fulfilling the natural forcial conditions.

the indications would be in the shape of the electric, calorific or magnetic properties of force.

The tangibility of matter, as also the peculiar structures through which one body is gold, another silver, another coal, another diamond and another water are, of course, dependent upon the action of some one or several combined phases of force, and in the same manner the manifestation of force, as also its peculiar conditions which exhibit at one time sound, at another light, at another heat, electricity, magnetism, cohesion and adhesion, are dependent upon the conditions provided by matter. We can bring about the manifestation of any force that we desire, simply by arranging the material conditions in such a manner as previous experience has taught us will produce it; for example: we know that any two metals of differing potentials, placed together in any liquid, even water, will bring about the manifestation of electrical force. And by the same observance of material conditions we can produce heat, sound, light, cohesion, etc., etc.

This line of reasoning followed to its legitimate outgrowths, would naturally lead us to the apprehension of a world immaterial in In nearly all such cases the conjunction of its nature, and where immaterial but substan- force is essential to produce the material contial existence was possible in the full exercise ditions, and in the majority of instances such of all the faculties of mentality and conscious-assisting force properties disappear in accordness, where we could possess the same func-ance as the new property is produced. But this tions of living and thinking as at present, mod- does not necessarily prove that there has been ified only by elimination of the conditions nec- a conversion of one form into another, but essary to terrestrial affairs, and the addition may be taken just as logically and more reaof those required by a more ethereal, but nev-sonably to demonstrate that the material conertheless a positively proven, real state. We ditions having been altered, its particular propwill not, however, in this article enter into this erty being no longer provided with opportunity branch of the subject, but will leave it for the for manifestation in much the same sense as the consideration of our readers, promising in the material property of brittleness is often dissifuture to venture a few thoughts and sugges-pated by the introduction of new structural tions in connection therewith, confining this conditions, while the new force property which paper more particularly to an examination of appears simply demonstrates that soil has been the physical forces of nature in their con- provided for it. Force, in its crude or indefinite nection with material phenomena from the state, is everywhere present ready for constant standpoint above hinted at. action under all the material conditions provided, while under the differing material conditions, it manifests itself in its differing properties. All these properties arise from the same original, crude force at work, with the only difference that the work being done has taken a definite shape.

If it can be demonstrated that there is a resemblance between the world of matter and the world of force, in that both could have had independent existences in their primeval stages, as matter, however attenuated, and as force, however sublimated, it is reasonable to suppose that the developments achieved by one along its particular line would also be possible to the other in its line. Therefore, as all the phases of matter are simply properties, qualities or conditions of originally crude matter acted upon by an extraneous source, so also is it reasonable to suppose that all the various phases of force are simply properties or conditions of an originally crude force in much the same sense as brittleness, opacity, ductility, malleability, etc., etc., are simply properties of matter, and that when we speak of heat-force, sound-force, electric-force, etc., we shall understand them to be simply conditions or properties of the force-element, by which certain conditions are produced, and not original force-creations generated at the particular moment of their exhibitions. In the same sense as matter is undeniably dependent upon the action of force for its various conditions, so force is unquestionably dependent upon material conditions for its manifestations. The arrangement of the particles in a certain manner as in the vibrating tuningfork, and an opportunity for the action of force is provided which indicates itself in the manifestation of sound, while should the same piece of metal be placed under other conditions

(Continued from page 14, vol. viii.) What is Sound? The Substantial Theory versus The Wave Theory of Acoustics. BY GEORGE ASHDOWN AUDSLEY, F.R.I.B.A.

I feel I have said very little on this great subject, and that little very badly; but I must now leave argument in words for argument in experimental demonstration. Time will, however, only permit of a few experiments, and that in the direction of showing you upon what very shallow arguments and wrong conclusions the wave theory of acoustics has been supported by its greatest advocates. As I pass on you will see how perfectly the theory of substantial sound force accounts for each and every phenomenon.

By way of an introduction to my first experimental demonstration of the nature of sound, let me direct your attention to the different teaching of the old and new theories of sound.

According to the wave theory we are taught that sound-waves, mechanically generated by the vibrating or exploding body, are capable of mechanically moving, shaking or breaking other bodies against which they strike; whilst,

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cludes the Professor, "has passed through both smoke and air without carrying either of them along with it."

Now, I have no wish to be disrespectful, but I can not help asking the simple question-if any sane man can accept Professor Tyndall's experiment as a proof of the wave theory of sound, or believe his explanation of the whole matter?

I shall now perform the experiment before you exactly as Professor Tyndall performed it before his audience in the Royal Institution, in direct support of his favorite theory of sound; and then I shall conduct it as I think it ought to have been performed on that occasion, but was not, probably because its results would in no way have supported the

according to the substantial force theory, we are assured that sound force, however great its volume may be, is absolutely incapable of moving a cobweb, or any body whatever which is not in vibrational sympathy with that sound force. Or, as Dr. Hall puts it, "The differences between theoretic air-waves, according to the current theory, and pulses of sound force according to Substantialism, is this: the air-waves are supposed to be purely mechanical in their operation, striking any and all objects in their way with the same force according to resisting surface. On the contrary, pulses of sound force are supposed to act on no material object that is not in vibrational sympathy with them, any more than substantial rays of magnetism will act on a piece of wood or other body not in mag-wave theory. netic sympathy. There is no more necessity Here is a tube similar in form to that used of assuming air-waves to be sent off from the by Professor Tyndall, but much shorter. I vibrating instrument to beat against the prefer to use a short tube because the tests I tensioned string, diaphragm or flame, to cause subject the whole question to are very much its motion, than there is of assuming that more severe and conclusive with it than with the magnetism which lifts the distant iron a 15-foot tube. I place a lighted candle, with bar does it through some action exerted upon its flame immediately opposite the smaller it by the connecting atmosphere. If the im- orifice, and on clapping my hands at the other material but substantial force of magnetism end the flame instantly "ducks down." Now, can produce physical displacement of a pon- on clapping two books together the candle derable body at a distance, why can not sub-is blown out. Such were the results obtained stantial but immaterial sound force do the by Prof. Tyndall; but is there a single person present on this occasion who believes for one instant that sound had anything whatever to do with either the disturbance or the extinction of the flame? Surely not. Yet Professor Tyndall assured those who witnessed the similar experiment in the Royal Institution that both effects were caused by a sound-wave a pulse and not a puff of air." We can not help thinking that the distinguished lecturer paid a very poor compliment to the common sense of his hearers, whilst he taxed their gullibility to the utmost. I need not waste time with the part of the original experiment which ended in smoke, but may pass on to my version of the experiment.

same under a different law of nature?" Now for our first experiment.

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If you turn to the opening pages of the leading English text-book on acoustics, Professor Tyndall's "Sound," you will find, in the paragraphs devoted to the "Confinement of soundwaves in tubes," a very remarkable experiment described-the experiment I am now about to show you, just as Professor Tyndall performed it in the Royal Institution before a scientific audience, and then as I think it ought to be completed so as to get out its full teaching. Professor Tyndall thus clearly describes his remarkable experiment: "The weakening of sound, according to the law of inverse squares, would not take place if the I relight the candle and place it, as before, sound-waves were so confined as to prevent its opposite the small, conical end of the tube; lateral diffusion. By sending it through a and on the flame becoming perfectly still, I tube with a smooth interior surface we ac- proceed to test the effect, not of simply discomplish this, and the wave thus confined turbed air as in the previous case, but of may be transmitted to great distances with powerful and true sound force upon it. I now very little diminution of intensity. Into one take this horn, which is capable of yielding end of a tin tube, fifteen feet long, I whisper very loud and sudden sounds--much louder than in a manner quite inaudible to the people any that can be produced by clapping books tonearest to me, but a listener at the other end gether-and placing its bell directly opposite hears me distinctly. If a watch be placed at the larger end of the tube, I produce several one end of the tube, a person at the other end varieties of sound, loud and soft, short and sushears the ticks, though nobody else does. At tained, yet to none of these does the candle the distant end of the tube is now placed a flame "duck down" or show the slightest dislighted candle. When the hands are clapped turbance. Here, notwithstanding that the air at this end, the flame instantly ducks down at at the bell of the horn is necessarily disturbed the other. It is not quite extinguished, but it by that blown into the instrument from my is forcibly depressed. When two books are mouth, we have no sudden_concussion, no clapped together, the candle is blown out. puff of wind, as in Professor Tyndall's soundYou may," continues the Professor, "here wave version of the experiment, but simply observe, in a rough way, the speed with sound pure and simple; and this sound, or which the sound-wave is propagated. The sound force, passes through the short tube instant the clap is heard the flame is ex- and through the flame without finding anytinguished. I do not say that the time re-thing in sympathy with it, and accordingly, quired by the sound to travel through this without disturbing anything. Now what can tube is immeasurably short, but simply that the interval is too short for you to appreciate it. That it is a pulse, and not a puff of air, is proved by filling one end of the tube with the smoke of brown paper. On clapping the books together no trace of this smoke is ejected from the other end. The pulse," con

the wave theorist say regarding Professor Tyndall's original experiment and my extension of it? Is it not self-evident that if the former supports the wave theory with its mechanically set up air-waves, the latter hopelessly refutes that theory? But even Professor Tyndall's experiment goes in no

way to support his theory, simply because it was a sudden gust or puff of compressed wind which literally blew the candle out, and not sound of any kind. Any one with a grain of common sense can see this, and it seems absurd insisting on the fact.

I have here a more perfect piece of apparatus, devised by myself, for the purpose of proving, in the first place, that vibrating sonorous bodies, while sending forth sound, do not disturb the air to any appreciable distance from their surfaces, and, in the second place, that the sound they send forth is incapable of moving or in any way affecting the lightest substances, or any substances or bodies whatever, which are not in perfect sympathy with the source of the sound.

I feel that it is somewhat rash on my part to enter on so complex a subject in this short Paper, for it would require at least a full Lecture to do it justice. It is, however, quite necessary that it should be touched upon on the present occasion for the better understanding of my arguments.

this wonderful little instrument acts when sonorous vibrations reach it. Imagine the violin string vibrating 500 times in one second. The sounding-board also makes 500 vibrations in a second. The air touching the violin is set trembling with 500 tremors a second, and these tremors speed with a velocity of 1,100 feet in a second in all directions through the surrounding air. They soon reach the drumskin of the ear. The latter, being elastic, moves in and out with the air which touches it. Then this membrane, in its turn, pushes and pulls the little ear-bones 500 times in a second. The last bone, the little stirrup, finally receives the vibrations sent from the violin string, and sends them into the fluid of the inner ear, where they shake the fibers of The tuning-fork has been selected as the the auditory nerve 500 times in a second. sound-producing body, because it is the These tremors of the nerve-how we know favorite instrument in the hands of the not so affect the brain that we have the acoustician for proving the existence of sensation which we call sound." We are sound-waves, and for illustrating the mechan- further assured by this eminent scientist that ical action of those waves, as I shall show the description "just given is not that of a when I come to speak of sympathetic vibra-picture created by the imagination." We shall tion and interference of sound. The remain- see! ing portion of the apparatus consists of a wooden tube, open at both ends, and furnished with small glass windows in the center of its sides. Suspended within and between these windows is a strip of gold-leaf, almost filling up the air-way of the tube. The tube has a long slot cut in its lower side so that it can be moved over the prongs of the vibrating fork; It is probable that the illustration given by or, what is more convenient, the fork can be Professor Mayer may not at first strike one as moved, after being bowed, into the tube. containing any element of impossibility or Allowing the gold-leaf to hang perfectly still, absurdity, and if the tympanic membrane was I set the large fork into full vibration, and merely taxed to vibrate with one uniform then push it into the tube until one of its motion, at one uniform rapidity, and to prongs is quite close to the gold-leaf screen. transmit only one sensation or impression to If we are careful not to disturb the air, we the auditory nerve and brain at one time, we shall fail to observe the slightest flutter or might, perhaps, pause before boldly questionmovement of the leaf. Why is this? The ing the truth of the whole matter. But let us wave theorist is bound to maintain that all think for a moment of what the tympanic the while sound-waves are being generated by membrane is called upon to do in accordance the vibrating prong, and that they are sent with the imperative demands on the wave off, with condensations and rarefactions, 4 theory of sound, and our reason at once starts feet 4 inches long, at the uniform rate of 256 out in open revolt at the mechanical imposin each second of time, and at the velocity of sibility it is asked to recognize as fact. Have about 1,120 feet a second. The puzzle is how you, musicians, in listening to a grand Symphthese waves-potent enough, in Professor ony, performed by an orchestra of a hundred Tyndall's estimatiou, to blow out a candle-instrumentalists, tried, whilst you heard the manage to pass directly through the sensitive united harmonies of all, and whilst you easily gold leaf screen without moving it. Here I followed the sounds of each class of instru might say, in the language of our greatest ment engaged, to realise what your tympanic poet, "I pause for a reply." membranes were called upon to do according to the popular scientific hypothesis? If not, do so, and let your reason and common sense lead you to a true conclusion.

As we are taught by the undulatory theory of acoustics that the sensation of hearing is caused by sound-waves or mechanically set up air-waves striking against the tympanic membranes of our ears and bending them in and out, it is highly desirable that we should, at this point, consider this important question connected with our sense of hearing, and strive to arrive at something like a true and logical conclusion anent the office and action of the ear.

The function of the ear is thus described by Professor A. M. Mayer, America's greatest wave theorist. He says: "Sound is the sensation peculiar to the ear. This sensation is caused by rapidly succeeding to-and-fro motions of the air which touches the outside surface of the drum-skin of the air. These twoand-fro motions may be given to the air by a distant body, like a string of a violin." After briefly describing the structure of the ear, the Professor continues: "Let us consider how

As I have given you the views of one great American scientist on tympanic vibration as caused by a single violin string vibrating 500 times in a second, let me now, in preference to any imperfect words of my own, give you the views of another American authority, Professor G. R. Hand, on the other aspect of tympanic vibration. "Substantialism is thundering at the gates of Popular Science, and demanding a re-examination of the facts and proofs of the undulatory theory of sound. Tympanic vi bration opens the portals of her secret chambers and extends a cordial welcome to her auditorium. We enter for a few moments, and take hasty cognizance of the beauties and inconsistencies that press themselves upon our consideration, as the ear-drum labors with herculean efforts to convey intelligent sounds to the auditory nerve, according to the

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