by Grant Allen
The coincidence came about in this way. My friend Edward Clodd submitted to me in the summer of 1885 the first rough sketch of his recent work ‘The Story of Creation.’ In discussing with him the outline of that book, and especially certain points connected with his conception of Force as there embodied, I found he had lighted upon some of the self-same fundamental difficulties which had originally led me to the views set forth in this little volume. In the course of our conversations on these moot questions I ventured very gently to hint at my own heresies, while disclaiming any desire to poison his mind with them: indeed, so anxious was I not to mislead my friend in this matter that it was with great reluctance I at last consented to lend him the old and crumpled manuscript of my early essay. On reading it over, he told me it had entirely dissipated his difficulties, and had set the whole question for him in a new light. Furthermore, to my unfeigned dismay and distress, he announced that he intended to embody the theory in outline in the dynamical portion of his forthcoming work. Much alarmed, I endeavoured to dissuade him from so rash a course, seeing that like myself he was no physicist, and that the doctrine was new, strange, and heterodox: but so great was his confidence in the truth of the theory that my protests fell flat upon unwilling ears. He incorporated the heretical conception in ‘The Story of Creation,’ and, as I feared beforehand, suffered not a little for his generous rashness at the hands of the critics.
A monomaniac who has found one other person to share his monomania might perhaps have been excused for jumping to the conclusion that the rest of the world would probably give him a fair hearing. But I was far too afraid of mathematical opinion to venture even so upon publishing my probably crude and incorrect ideas. I still refrained from any attempt to print my book, till I saw that the attacks upon Mr. Clodd’s position almost made it a point of honour for me to lay the facts in their integrity before the judgment of the scientific world. It was not right my friend should suffer for my own transgression. Criticism was levelled at the necessarily brief and bald abstract he had given of what I may venture to call our joint opinion: I thought it only proper, in justice to him, that the theory as a whole should be put in evidence for the jury of experts to examine and decide upon. I don’t for a moment suppose they will take the trouble to look into it at all: but at any rate I have now discharged my duty — liberavi animam meam — the evidence is here, and who will may consider it.
Nobody could be more sensible than I am how little likely it is that a mere amateur should hit upon a true generalisation in science missed by the recognised leaders of physical thought. For this reason, I would never have published my treatise at all (profoundly as I myself believe in it) had it not been for Mr. Clodd’s intervention, with its remoter consequences. As it is, however, I may plead in extenuation this further excuse. The thoughts one entertains, says the greatest of living English thinkers, are as children born to one which one may not willingly let die. There can be no harm, therefore, in putting them forth to the world, in a tentative way, with all due modesty, provided always it is clearly understood that they are put forth as suggestions alone, for wiser heads to accept or reject at leisure. If perchance it should happen that one has indeed hit almost by accident upon a true and luminous principle, one owes it to humanity to set that principle forward at once, in spite of the natural fear of criticism and ridicule. The would-be discoverer is probably wrong: but when by any stroke of luck he chances to be right, it is for the good of the world that he should publish his discovery. In this light, therefore, I venture to beg the professional critic to examine my work. It pretends to be no more than a suggestion, an aperçu, an attempt at a theory: I ask for it nothing better than honest consideration: for if this counsel or this work be of men, it will come to nought: and I have no desire to aid in the promulgation or diffusion of error.
For the same reason, I will not apologise for the seemingly dogmatic mould in which the treatise itself is cast. Being nothing more than an endeavour to express in words the fundamental dynamical constitution of the universe, as it envisages itself to a particular inquirer, I have thought it best to use the purely impersonal form, and to state each proposition as simple fact, leaving the reader to bear in mind for himself throughout, that the whole is suggestion or conception merely.
At the same time, I sincerely trust scientific readers (if I am fortunate enough to attract any) will approach the theory with an unbiassed mind, and instead of rejecting it offhand at the first glance, because its conceptions do not agree with those to which they are already accustomed, will do me the justice to read it through before deciding, and to place themselves as far as possible in sympathy with my point of view. I grant at once that the idea of Energy they will here find embodied is not at all the idea hitherto framed by men of science. It is a new idea; and that is exactly why I have written this little treatise. If I am right (as I probably am not) our concepts of Energy will have to undergo a considerable revision. That being just the question at issue here, I hope readers will duly consider it, instead of taking the current view dogmatically for granted, and crushing me by pointing out that mine does not coincide with it. A petitio principii is no refutation.
The long time I have kept this treatise by me unpublished ought to supply sufficient proof of the extreme timidity with which I myself regard it. That timidity may perhaps be allowed to protect me from harsh, unkindly, and contemptuous criticism. If I am wrong, of course, I shall expect to be frankly told so: I shall accept demonstration of my mistakes and misconceptions with a good grace. Naturally, I shall continue still to think myself right: it is not in human nature to do otherwise: the theory has too long interwoven itself into all my conceptions of the physical world to be easily rooted out of the fibres of my brain now after so many years. But having once consented to trot out my little heresy unwillingly before the eyes of the world, I shall drop it in public henceforth and for ever. I will make no angry replies to authoritative expositions of my blunders or errors: I will abstain from imitating the common paradox-monger, who, hardened in his obliquity, sees only unfair attacks and unworthy motives in demonstrative criticism. ‘I’m not a-arguin’ with you; I’m only a-tellin’ of you,’ said a pothouse politician to an obtuse friend. I don’t expect to be argued with: I shall be satisfied to be told.
Under these circumstances, and in consideration of previous good conduct, I earnestly trust the court of scientific opinion will let me off with a caution or a nominal fine. My promise never to recur to the subject again may surely in such a case be counted to me for righteousness. At a certain college examination, where proof of age was required from all intending candidates, a certain colonial-born undergraduate brought with him perforce his only documentary evidence, a certificate of baptism. The examiner, a well-known heterodox don, glanced at the ecclesiastical certificate curiously. ‘How’s this?’ he asked in a hurried voice. ‘How’s this? You’ve been baptised, sir?’ The luckless undergraduate timidly stammered out that it was a mistake due to the imperfect registration system of his native land. ‘H’m,’ snorted the examiner: ‘oh, very well, then: as you were baptised by mistake, it won’t be allowed to tell against you.’ May I venture to express a humble hope that on this occasion too a heresy extorted from me under such peculiar circumstances will not be allowed to tell against my character?
Part I.
ABSTRACT OR ANALYTIC
CHAPTER I.
POWER.
A POWER is that which initiates or terminates, accelerates or retards, motion in one or more particles of ponderable matter or of the ethereal medium.
Power, as here understood, is thus the widest of all possible dynamical conceptions. It cannot be defined by genus and differentia, because it is itself the summum genus of dynamical science. Accordingly, it will be observed that no attempt is made above to assign it to any higher class, such as things, entities, or concepts. Nothing would be gained, for example, by saying that a power is the tendency to initiate or terminate motion: it is best described by
the indefinite statement given at the head of this chapter. It is simply that which produces or destroys, increases or lessens, motion in any particle or particles of any substance whatsoever cognisable by man.
Powers are of two sorts, Forces and Energies, the differences between which will be fully set forth in subsequent chapters. Meanwhile, as a help to the provisional comprehension of the nature of Power, which can scarcely be grasped at first in the abstract terms of our formal definition, it may be mentioned that amongst the varieties of Power are such Forces as Gravitation, Cohesion, and Chemical Affinity, besides such Energies as Heat, Electricity, and Light. These expressions are here employed in their popular sense, merely as guides to the sort of concept provisionally set forward for the term Power, until the subsequent investigation has rendered possible a more rational and comprehensive notion in the mind of the reader.
CHAPTER II.
FORCE.
A FORCE is a Power which initiates or accelerates aggregative motion, while it resists or retards separative motion, in two or more particles of ponderable matter (and possibly also of the ethereal medium).
All particles possess the Power of attracting one another — in other words, of setting up mutually aggregative motion — unless prevented by some other Power of an opposite nature. Thus a body suspended freely in the air is attracted towards the earth by the Force (or aggregative Power) known as Gravitation. A piece of sugar, held close over a cup of tea, attracts into itself the water of the tea-cup, by the Force (or aggregative Power) known as Capillarity. A spoon left in tea grounds or a foot planted on the moist sand similarly attracts the neighbouring drops. A piece of iron or coal exposed to free oxygen (each at a certain fixed temperature) attracts the particles of oxygen by the Force known as Chemical Affinity. In every case there must be an absence of counteracting Energies (or separative Powers) sufficient to prevent the union of the particles, as will be shown hereafter: but for the present it will be enough to notice that every particle attracts every other particle in some one of various ways, unless prevented by other Powers.
Not only, however, do all particles thus attract one another, but they also resist all attempts to separate them from one another. A weight suspended in the air falls to the ground: but it also resists any attempt to remove it from the ground, which can only be done by the employment of a proportionate Energy (or separative Power). The water which the sugar has absorbed can only be drawn from it by the Energy of suction. The oxygen with which the iron has united can only be driven off by the Energy of heat: while the carbonic anhydride and water which resulted from the burning of the coal yield only as a rule to the separative Energy of light or electricity. In every case the Force which brought two or more particles together in the first instance keeps them united ever after, and must be neutralised by an equal Power of an opposite description before they can be disjoined.
CHAPTER III.
ENERGY.
An Energy is a power which resists or retards aggregative motion, while it initiates or accelerates separative motion, in two or more particles of ponderable matter or of the ethereal medium.
All particles, or aggregates of particles, not actually in contact with one another in stable equilibrium at the absolute zero of temperature, are kept apart by an Energy or separative Power of some sort, which prevents them from aggregating as they would otherwise do under the influence of the Forces inherent in them. Thus the moon is prevented from falling upon the earth, and the earth from falling into the sun, by the Energy of their respective orbital motions. A ball shot from a cannon into the air is prevented from falling by the Energy of its upward flight. A red-hot poker has its particles kept apart by the Energy of heat. In every case, so soon as the Energy is dissipated (as hereafter explained) the ball yields to the aggregative Power of Gravitation, and the poker contracts to its ordinary dimensions; while there is no reason to doubt that under similar circumstances the moon and the earth will aggregate with the sun. The particles of water are kept in the liquid state by the Energy known as latent heat, and so are those of steam: when the ‘latent heat’ is dissipated, the steam condenses and the water freezes. There are many apparent exceptions; but they will be considered at later stages of the argument. For the present, the reader must be content to understand the word Energy (when used in this treatise) only in the sense here given to it of a Power which resists or retards aggregation.
Energies also initiate separative motions. Thus, a cannon ball is raised by Energy to a distance from the main mass of the earth which usually holds it bound by Gravitation on its surface. A poker placed in the fire has its particles separated from one another by the Energy of Heat. When ice melts or water is converted into steam, the same Energy similarly severs their particles from one another and places them in positions of relative freedom. In the electrolysis of water the Energy of the galvanic current tears asunder the atoms of hydrogen and oxygen from their close union in the compound molecule. In short, wherever we see masses or particles in the act of separating from one another, we know that the separation is due to some Energy.
CHAPTER IV.
THE SPECIES OF FORCE.
Forces may be most conveniently divided according to the nature of the particles or bodies in which they initiate and accelerate aggregative motion or resist and retard separative motion. Of these, there are four principal kinds known to us or conjectured by us. The first kind is the Mass or visible aggregation of particles, which admits of mechanical separation into minor masses. The second kind is the Molecule, or ultimate mechanical unit, which does not admit of subdivision, except by resolution into its chemical components. The third kind is the Atom, or ultimate chemical unit, which does not admit of subdivision by any known means, though it may perhaps be resoluble hereafter into some simpler and more primitive units. The fourth is the Electrical Unit, whose nature is very inadequately known to us, but which must be considered for our present purpose as in some way the analogue of the others, though we have no sufficient warrant for giving it any material properties.
The Force which aggregates Masses and resists the separation of Masses is known as Gravitation. When any two Masses are left free to act upon one another without the counteracting influence of an Energy, they aggregate in obedience to this Power. When the cannon ball falls upon the earth, it is Gravitation which draws them together. When an aërolite comes within the circle of the earth’s attraction, it is Gravitation which makes them leap towards one another. If the moon were to lose its orbital Energy, Gravitation would pull it to the earth; and if our planet in her turn were suddenly checked in her course, Gravitation would cause her to plunge into the sun, while the sun in return would make a slight bound to meet her. Again, when any two Masses are in a state of aggregation, the Force of Gravitation resists any attempt to sever them. If the cannon ball lies upon the ground, it cannot be raised without an expenditure of Energy, and the amount of the Energy required to lift it to a given height (or distance from the surface of the earth) is the measure of the resistance offered by Gravitation. Similarly, when the Masses are not in actual contact owing to the existence of an Energy which keeps them apart, as in the case of the earth and her satellite, or the sun and the planets, Gravitation resists any attempt to sever them beyond their actual distances. It would be impossible to remove the moon a hundred miles from the earth, or the earth a hundred miles from the sun, except by the employment of an adequate Energy; and, as in the simpler case, the amount of Energy required would be the measure of resistance offered by Gravitation.
The Force which aggregates Molecules and resists the separation of Molecules is known as Cohesion. When any two Molecules are left free to act upon one another without the counteracting influence of an Energy, they aggregate in obedience to this Power. But the cases are much more difficult to illustrate than those of gravitation, because while masses attract one another powerfully at very conspicuous distances, Molecules (practically speaking) only attract one another at infinitesimal distances. The
difference, however, which is purely relative, may thus be illustrated and explained. An aërolite is not drawn on to the earth unless it approaches the earth very closely, because otherwise the earth’s attraction, though causing a deviation in its course, does not suffice to overcome the aërolite’s energy and the combined attractions of surrounding bodies. But if it be near enough to be more powerful than all of them put together, the aërolite either circles round the earth as a satellite or even falls at once upon its surface. Similarly with Cohesion. If two pieces of uneven iron be laid upon one another, the molecules do not approach near enough to exert any conspicuous mutual influence: but if the two pieces be planed to an absolute smoothness, so that the several molecules can come within the sphere of their mutual attraction, they will cohere perfectly, and it will be impossible to tear them asunder. Again, in other cases, Cohesion can only be effected by such a molecular motion (or heat) as will cause the Molecules to approach one another closer than they can be induced to do by mechanical means: just as an aërolite which would not under ordinary circumstances come (practically speaking) within the sphere of the earth’s attraction, might do so if it were given an oscillating motion from side to side, so as to cross or closely approach some portion of the earth’s orbit. Thus, two pieces of iron, if heated, will cohere with one another. Furthermore, the molecular motion inherent in the liquid form is often sufficient for this purpose: thus, two masses of dough, which will not cohere in the dry condition, can be made to do so by the addition of moisture. In the practice of gumming and glueing, we make use of this device in everyday life. A further account of these phenomena will be given in the chapter on Liberating Energies. The second property of Cohesion, that of resisting the separation of Molecules actually aggregated, is much more familiar to us. If two Molecules or bodies of Molecules are in an aggregated condition — that is, are not rendered plastic or liquid or gaseous by some form of Energy — we cannot separate them without a considerable expenditure of Energy. The Energy may be in the form of a mechanical action, as when we tear or break a cohering substance; or of heat, as when we melt lead; or of the contained motion of liquids, as when we dissolve a lump of sugar. But in any case Energy must be expended to counteract the aggregative Force of Cohesion in solid bodies.
