Front Page Titles (by Subject) APPENDIX.—No. V.: SOURCES OF MOTION. - The Works of Jeremy Bentham, vol. 8 (Chrestomathia, Essays on Logic and Grammar, Tracts on Poor Laws, Tracts on Spanish Affairs)
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APPENDIX.—No. V.: SOURCES OF MOTION. - Jeremy Bentham, The Works of Jeremy Bentham, vol. 8 (Chrestomathia, Essays on Logic and Grammar, Tracts on Poor Laws, Tracts on Spanish Affairs) 
The Works of Jeremy Bentham, published under the Superintendence of his Executor, John Bowring (Edinburgh: William Tait, 1838-1843). In 11 vols. Volume 8.
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SOURCES OF MOTION.
Analytical Sketch of the several Sources of Motion with their correspondent Primum Mobiles.
Of Motion in general—its generation and extinction.
In the masses of matter with which man is conversant, and on which for his being, as well as his well-being, he is at all times dependent, whatsoever change is effected—this change is either itself some motion, or owes its origin to some motion of which it is the result.
Motion is the motion of some body or bodies; of some portion or portions of matter, of the aggregate mass of matter with which man is conversant.
Of this aggregate mass no particle can at any time, or in any place, in any direction, enter or be made to enter into a state of motion, without having to encounter a perpetual and indefatigable antagonist styled Resistance.
According to the commonly received distinction, this Resistance is susceptible of two different modifications; viz. 1. Counter Motion, i. e. active; and 2. vis inertiæ, or purely passive resisting force. But, perhaps, upon a closer examination it might be found, that that which presents itself in the character of a purely passive resisting force, is no other than an actively resisting force, produced by the elasticity of the mass to which the moving power is applied; that is, the repulsive power, the countermotion, or tendency to countermotion, of the particles of which the mass acted upon by the moving force is composed.
To one or other of these powers, if between them there can be any real difference, will be to be referred that cause, to the designation of which, when cessation of motion is considered as the effect of it, the word friction is applied.
For the purpose of rendering, in the best manner in which we are able, an account of the motion of such bodies as are in motion, and of the rest of such as are at rest, certain fictitious entities are, by a sort of innocent falsehood, the utterance of which is necessary to the purpose of discourse, feigned to exist and operate in the character of causes, equally real with, and distinct from, the perceptible and perceived effects, in relation to which they are considered in the character of causes.*
All bodies we are acquainted with, it is universally agreed, are compounds, as it were, of solid matter and empty space. All bodies, viz. the ultimate particles of solid matter which enter into their composition, are separated by intervals of space, in which no matter at all, at any rate none that we have any acquaintance with, is contained. To the different distances at which, in different states of its existence, the component particles of the same body are placed, are owing, in some degree, the different textures of which it is susceptible, and which, under different circumstances, it exhibits to our senses.
Take, for example, any mass of matter whatsoever: suppose an apple; the apple let it be from which Newton derived the first hint of the attraction of gravitation; the ever memorable apple which, as an object of worship to the latest posterity, ought to have been preserved from corruption in a hermetically sealed glass-case; ought to have been transmitted as an object of worship to the latest inheritors of this our globe:—the particles of solid matter of which this apple is constituted are, each of them at a certain distance from each of the several others. How happens it that they are not more distant. What is the cause of such their propinquity? The necessary fiction above spoken of provides an answer and says, the attraction of cohesion is the cause by the operation of which they are thus kept together. How happens it that they are as distant as they are? What is the cause of such their distance? Here again steps in the same useful respondent, and answers, It is by mutual repulsion that they are thus kept asunder.
It is to distinguish it from the attraction of gravity, of which presently, that the attraction, termed the attraction of cohesion, has acquired that name. Of this species of attraction, repulsion, it has been seen, is the constant companion, and antagonist; each of the opposite and mutually balancing effects have equal need of a fictitious cause. Repulsion is the generic name applicable to other cases. Attraction of cohesion is a specific one. To match with this its antagonist, the particular species of repulsion here in question requires its specific name. Repulsion corresponding to the attraction of cohesion, let this be that specific name; or rather an appellation thus multitudinously worded, being too cumbersome for use, say, the repulsion of cohesion: and though taken by itself, and without explanation, the appellative would, upon the face of it, be self-contradictory, yet by this explanation, to which by its texture it would naturally point, it may perhaps be found not altogether unfit for use. Instead of this appellation, or for variety along with it, if for attraction of cohesion, the appellation internal attraction, or intestine attraction, be employed; for repulsion of cohesion, the term internal repulsion, or intestine repulsion, may be employed.
In the Attraction of Gravity may be seen one of the fictitious entities, to the operation of which, in the character of causes or sources, the birth of motion, howsoever modified, may, as far as we are acquainted with it, be referred. To the repulsion of cohesion—to this one simple cause, will, it is believed, be found referable, with equal propriety, the death of all these several motions; which, at the conclusion of the conflict maintained by the various species of attraction, endowed with their several unequal degrees of force, remains, constituting the only force by which matter is retained in that state of composition above-mentioned, which seems essential to its existence; and by which the whole multitude of its particles are prevented from being crowded together into one mass.
To account for the difference of bodies in point of distance, a sort of nominal entity is feigned, to represent the cause of it, and Motion is the name by which this imaginary cause is designated. Motion is thereupon considered (for such are the shifts that language is reduced to) as a sort of receptacle in which bodies are lodged; they are accordingly said to be in motion, as a man is said to be in a house.*
By laying out of consideration everything that concerns the particular nature of these bodies respectively; everything, in a word, concerning them, but the difference between the distance or interval between them at the one time, and the distance or interval between them at the other, we obtain the abstract idea, for the designation of which the word motion is employed. In speaking of it, we speak of it as if it were itself a substance: a hollow mass into which the body, the really and independently existing body, whatever it be, and how vast soever it be, is capable of being put, and which is capable of being communicated to that body, and so in regard to bodies in any number.
A philosopher, says the old Greek story, denying the existence of Motion, another to refute him, got up and walked. Good for a practical joke, not so for a serious refutation. Of the existence of the faculty of locomotion, the denier of the existence of motion, was not less perfectly aware before the experiment than after it. What he denied was,—not the universally exemplified, and universally known, and acknowledged matter of fact, that the same body is at one time in one place, at another time in another, and in that sense the existence of motion—but the existence of any real entity, corresponding to the appellation motion; any entity real and distinct from the body or bodies in which the motion is said to have place.
Thus early (as appears from this story) had a conception, however narrow and inadequate, been formed of the distinction between names of real entities and names of fictitious entities;† a distinction by which much light has already been thrown, and by degrees much more will be thrown on the field of language; and through that medium, on the field of thought and action; and, in particular, on the nature of the relation between cause and effect. Cause, when the word is used in its proper signification, is perhaps in every instance the name of a fictitious entity; if you want the name of the correspondent real entity, substitute the word author, or the word instrument, to the word cause.
Rest is the absence, non-existence, or negation of this imaginary receptacle. When, after observation taken of the two bodies in question, at two different points of time, no such difference of distance is found, they are said to have been during that length of time each of them at rest. Rest is thus a sort of imaginary pillar, or anchor, to which, in the English language, they are considered or at least spoken of, as being fastened.‡
Enclosed in that receptacle, or fastened to this pillar or anchor,—one or other is at every point of time the condition of every object to which the name of body has been attached.
The truth is, that absolutely and properly speaking, in as far as observation and inference have extended, motion is the state or condition in which, at every point, every body is, and so for ever is likely to continue. Rest is not the state of our own sun, about which the planet that we inhabit moves. If a state of rest were predicable of anything, it would be of the ideal point in the expanse of space, the centre of gravity, as it is called, about which, the sun on the one part, and the planets on the other, are observed or supposed to turn. The observations and inferences thus applied, in the first instance, to our sun, have been extended to those other bodies to which, to distinguish them from those companions to our earth called planets, we give the name of fixed stars; but which, determined as they have been by these observations and these inferences, it has seemed good to our astronomers not to tie to the above-mentioned pillar, but to put all together into the above-mentioned receptacle.
So it is then, that, for the purposes of discourse, as well as of thought and action, the pillar is not less necessary to us than the receptacle. For this purpose, rest requires to be distinguished into absolute and relative. Absolutely speaking, as above, no one body is at rest; but on this our little planet, the theatre of all our little doings and sufferings, bodies in abundance are to be found, which, as between any two given points of time, having been at the same distance from each other, have, during these two points of time, together with the whole interval, if any, that has been between them, been at rest. Upon the whole, then, absolute rest is not exemplified anywhere; but, on the surface of our planet, exemplifications of relative rest may be found everywhere. These things considered, henceforward as often as rest is spoken of as having place, relative rest, and that alone, will be intended.
The motions in which the various effects, as yet observed by us to be produced by the powers of nature, modified or not modified by human art and industry, have their essential causes, are derived from various sources. Of these motions, obvious, as when once brought to view, the task of giving a list may seem to be—obvious, and, by its conduciveness to the purpose of instruction, presenting an incontrovertible claim to the notice of the institutional writer, who, for the theatre of his labours, has chosen the field of Natural Philosophy,—the task of giving such a list, hath, it is believed, as yet, been undertaken by no one. No work in which that task has been executed, or endeavoured to be executed, is as yet anywhere to be found.
Consideration had of the utter absence of all information from more competent hands, to the author of these pages, how little soever accustomed to apply his industry to this department in the field of science, it occurred that an attempt to afford, in a manner however inadequate, a supply to this deficiency, might have its use, were it only by attracting to so interesting a subject, which presents so strong a claim to their notice, the attention of those from whose more adequate learning and ingenuity it may receive more correct and complete explanation.
Of these various sorts of motions, some are, as far as we have reason to believe, in their nature perpetual, unintermitting, or, if a common figure of speech may be allowed, immortal. Others, and by far the greater number, in their nature mortal and perishable.
Of these two so materially different heads, Which come under the former? Which under the latter? In any attempt to give answers to these questions, an answer to the question concerning the existence of what is called perpetual motion, is necessarily involved.
Of the following sketch the design is, in the first place, to perform the enumeration of the several distinguishable sources of motion, considered as it is wont to be produced, or capable of being produced by human art, in some determinate direction, for the purpose of accomplishing some determinate object or end in view. In the next place, by means of a systematical sketch, to bring to view the several points of relation between these several sources of motion,—the points in respect of which they agree with one another, and those on which they differ.
By this means a facility, it is hoped, will be given to the decision on the question, whether, in the preceding enumeration all such sources, actual and possible, are included; or whether any, and what are omitted.
Primum mobile is a term already in use; and by it, in each instance, is designated that mass of matter, which, when from the particular source in question, motion is considered as derived, is considered as being of all the bodies by which the motion is experienced, which, at the time in question, issues from that source, the first in which it has place. Accordingly, corresponding to every distinguishable source of motion, a primum mobile will be to be brought to view.
Of the two expressions, viz. sources of motion, and primum mobiles; the latter is the one, principally, if not exclusively, in use. To the other the preference has, notwithstanding, here been given, and that on several accounts.
1. It is only in as far as it points to the source whence it is derived, that the question, what or which is the first mover? (the body which, on the occasion in question, is of all the bodies in which the motion is observed to have place, the first in which it makes its appearance,) is an object of regard. In the class of objects designated by the generic word motion, men behold the cause of every effect, desirable or undesirable, which they perceive to take place. But various are the sources whence this important agent is seen to be derived. An object of anxious and continual research cannot but be, the determining, on every occasion, from which of all these sources, the article thus in universal demand, may be derived to most advantage.
Of this inquiry, source is the only direct and intrinsically important object: the primum mobile is so no otherwise than either in respect of its affording indication of the source, or, in respect of the need there is of commencing with this article, the plan of the operations instituted, for the deriving down to the ultimate object, whatsoever supply there may be occasion to draw from this source.
2. In many instances in which the source is sufficiently distinguishable to admit of a separate name, the primum mobile is altogether undiscernible; or, to speak more properly, a primum mobile is a thing that has no existence,—two bodies, or sets of bodies, move each of them towards the other, both beginning at the same instant of time; as is plainly the case, for example, in all those minute motions or dances of atoms, which belong to the experience of the chemical branch of science.
In a word, of the phrase, source of motion, the applicability will be seen to be universal; that of primum mobile, very confined; so much so that it is only in deference to usage, that any notice is here taken of it.
Sources of motion, enumerated with their corresponding Primum Mobiles: a sketch supposed to be all-comprehensive, and now, for the first time, attempted.
By the appellation Attraction of Gravity, stated also simply Gravitation, is designated the species of force by which, as far as observation or induction have extended, all particles of matter, without exception, are drawn towards one another: the heavenly bodies, commonly termed in contradistinction to planets, fixed stars, (they being comparatively such,) among the rest our sun, not excepted.
On this our earth a body is said to fall, when it is understood to come nearer to the centre of the earth than it was before. When to any mass of matter in the liquid state, it happens to fall otherwise than by means of the removal of some mass of matter in the vessel or state which had served for the support of it, in such case, antecedently to such its fall, it has by some assignable cause been made to rise. The only constantly, and regularly, and universally operating cause by which, on this our earth, water is raised, is the action of the moon. The mass of matter contained in that secondary planet, the motions of which are principally determined by those of that which we inhabit, operating in virtue of the universal principle of gravitation upon the whole mass of matter contained in ours. But in our planet, that part of its mass which is in a state of liquidity, or in a gaseous state, is free and able to yield, while that which is in the state of solidity, being kept together by another source of attraction, called Attraction of Cohesion, is not able to yield, any otherwise than the whole of it together. Hence, as the moon moves, while the solid part of the earth’s substance remains relatively and apparently stationary, the fluid part of the mass is perpetually in a state of relative motion, which is determined by that of the moon, and which, bating the disturbance it receives from winds, of which further on, would be a perfectly regular one.
In these circumstances, as it rises, any solid body floating on its surface is made to rise with it, and, as it falls, to fall; and thence in both cases, to operate with a force proportioned to its weight upon any body with which it is connected; and thus, from body to body, through any series of bodies, till the motion thus produced reaches that body or assemblage of bodies, on which, for the purpose of the practical use in question, the ultimately serviceable impression is intended to be made, to the end that the form adapted to that use may be given to it.
Laying out of the account temperature, and changes of temperature,—i. e. the quantities of perceptible heat in particular places,—viz. in the air, or other bodies, by which these places are respectively occupied;—laying out of the account temperature, and those other meteorological circumstances by which the fall of water, as will presently be mentioned—the fall of water in the shape of rivers—is produced, it is only by the attraction of gravitation, that has place between the earth and the moon, that this source of motion is afforded. Selenic or Selenigenous, is, therefore, a term which, if employed for the designation of this source of motion, will serve to indicate the characteristic nature of it.
Corresponding Primum Mobile, in this case the Moon: Secundum mobile, the water so made to rise and sink: Tertium mobile, the solid body which, floating on the water, is made to rise and sink with it: Quartum mobile, that part of any system of machinery with which the Tertium mobile is in immediate communication. The system of machinery in which use is made of this source of motion, and its corresponding Primum Mobile, is called a Tide-Mill.
A river is a mass of falling water—i. e. a mass of ice which, by mixture of a certain proportion of the matter of heat, is brought into a liquid state, and having, in such its liquid state, or at first in its state of solid ice, been dissolved in the air of the atmosphere and so raised aloft, is by means of a diminution in the proportion of caloric mixed with it, changed from the gaseous state into a liquid state, and by the attraction which, in common with all matter stationed at the surface, it has for the centre, of the earth, runs down till it arrives at a spot at which it finds its further immediate descent prevented by such portions of the matter of the earth as are in the solid state. In so doing, it acts and presses upon all bodies opposed to it, in such manner as to communicate, or tend to communicate, to them a quantity of motion not greater than that which it of itself possesses.
Corresponding Primum Mobile, in this case the falling water. Secundum Mobile, any moveable solid body placed, as in the case of the mainwheel of a water-mill, in such sort as to receive the motion which it is capable of communicating; and, therefore, to communicate it onwards according to the nature of the practical effect which, by the use of the water-mill, is intended to be produced.
Stereopiptic* source of Motion.
If, as in the case of water, any portion of that part of the earth’s surface which is in the solid state were by any regularly operating cause disposed to detach itself from the rest, and like the sand in an hour-glass, in obedience to the law of gravitation, approach nearer to the centre of the earth; if, for example, as in Africa and elsewhere, there are seas of sand, the fall of matter thus having place in a solid state might, as well as the fall of matter in a liquid state, in the way of communicating motion for the purpose of producing useful changes in the condition of bodies, be put to use.
But of any such fall regularly produced by the unassisted powers of Nature, no instance has ever been known; nor forasmuch as nature furnishes not for other substances, any such regularly operating causes of elevation as she does in the case of water, could it anywhere be of long continuance. It is, therefore, only for the purpose of illustration that, in the catalogue of sources of motion, motion thus produced is inserted.
But when, by human art and industry, for any particular purpose, in the instance of any mass of matter, whether in a liquid or in a solid state, a fall or descent has been produced, in this case, there is a source of motion which, by economy, may be turned to account. On this head, see No. 15, Economistic source of Motion.
Anemistic, or Aeropnutic source of Motion.
Considered in a state of motion, and in such quantity, and with such velocity, as to be capable of producing a considerable quantity of effect, any body, when in the gaseous state, is called wind. Of all bodies in a gaseous state, the only species which exists in a quantity sufficient to operate with regularity, in the character of a source of motion, is that in which by far the greater part of the contents of the atmosphere consist, viz. the mixture of oxygen gas and azote, with the occasional addition of carbonic acid gas, in considerable quantities, and many others in minute quantities.
Corresponding Primum Mobile in this case, the air considered as being in motion, and in whatsoever direction it may happen, viz. the wind. Secundum Mobile, any body which, for the purpose of receiving such quantity of motion as the wind is able to communicate, is opposed to it; for example, the sails of a windmill, and the sails of a ship.
Barometrical source of Motion.
Independently of the Motion, which, as in the case of wind, the air is liable to receive, from various causes, principally belonging to the head of temperature, i. e. change in the quantity of the matter of heat in a free state mixed with it, a motion in one particular direction, viz. a vertical one, and that as it may happen sometimes in the way of rise, i. e. increase of distance from the centre of the earth; sometimes in the way of fall, i. e. decrease of distance from the centre of the earth is almost continually impressed† upon all matter and, accordingly on all liquid matter, lying under it. If, while the quantity superincumbent on a certain portion of matter in a liquid state increases, the quantity superincumbent, on a portion of the like matter communicating with it, is kept from receiving increase, the consequence is, that the quantity of air thus insulated and detached from the rest, (being in a state of pressure determined by the altitude of the whole column of air, from the solid or fluid part of the earth’s surface in that spot, to the extreme limits of the atmosphere, while the other non-insulated portion was left free to receive the increase of quantity, and accordingly did receive it,) will yield to the greater pressure, and thus suffer the liquid matter to rise in the vessel in which the air has thus been kept in an insulated state.
The nature of things will scarcely admit of the applying of this source of motion with advantage, comparison being made with the other sources of motion which have been, and those which remain to be brought to view; so great is the quantity necessary to be kept in the insulated state; so great accordingly the expense of the receptacle in which it is to be kept, compared with the smallness of the quantity of motion capable of being thus produced, and the uncertainty at what time, and for what length of time, any motion at all will be thus producible. But, in the way of curiosity, a machine of this sort was once produced, and formed one of the articles comprised in the museum, called from the maker, Cox’s Museum, and disposed of in the way of lottery, under a special act of Parliament, in and by which this product of mechanical ingenuity was exempted from the operation of the law by which lotteries, made on account of individuals, stood prohibited.
In these circumstances, the air operates somewhat in the manner of the water in a tide-mill. Corresponding Primum Mobile, in this case, the air of the atmosphere considered in the state of simply vertical ascent and descent.‡
In all cases in which it is produced in any considerable quantity, Motion, when, by an exertion of will produced in an immediate way, or in any part of the body of a living animal, is, as far as the powers of observation extend, found to be produced by the shortening of a mass of muscular fibres.
For a long time, in all the cases in which, by the will of men, motion is to any purpose produced, for an indefinitely long period in the history of man this was the only source of motion drawn upon and employed; and in those assemblages of human beings which continue in the state of savage life, this is still the only source of motion that is employed.
In most cases, for the production of the effect ultimately in view, the motion derived from this source is employed in a direct way, and without the intervention of any such apparatus of bodies as is designated by the word instrument or machinery, employed for the gaining of power: machinery not being so much employed in giving direction or quality to motion derived from this source, as in giving direction or quality to motion derived from the above-mentioned and other more powerful sources.
But neither are instances by any means wanting, in which, even with the intervention of very elaborate and complicated systems of machinery, this source of motion is the only source employed; the machinery having for its object the production either of the particular direction desired or of velocity or time, at the expense of labour, or of quantity of matter put in motion at the expense of time, or of steadiness and regularity at the expense either of time, of labour, or of both.
By the mere contraction of muscular fibres, the greatest quantity of force employed, is that in which the animal force of some animal stronger than man—such as a horse, an ox, or an ass—is employed. In this case there are two different wills employed: that of the human being, and that of the inferior animal, whose will receives its impulse and direction from its human ruler. The will of the inferior animal is employed for giving birth to the motion; the will of the superior for giving direction to it.
Corresponding Primum Mobile, in this case psychological, the fictitious entity called the will; Secundum Mobile, the mass of muscular fibres thereby shortened; Tertium Mobile, the unbending parts of the animal machine, viz., the bones, according to the limb or other member on which the motion is impressed; Quartum Mobile, the external moveable body to which the motion thus generated is communicated in the first instance.
Parallactico-Suncrotic, or Alternate Gassification and Digassification Source, or Steam-Engine Source.
Elasticity, i. e. that property by which, while in virtue of the universally operating principle gravitation, these, as well as all other particles of matter, are attracted towards the common centre, and thence towards one another, they are (while in this state by the introduction of the matter of heat) made to repel one another. In the case of every body, so long as it remains either in a solid or in a liquid state, the field of the operation of this property has its limits, and those comparatively very narrow ones. In the case of the same body, when in the gaseous state it has no determinate limits: and the quantity of matter of all other sorts contained in the body being given, the degree of this elasticity, and thence the quantity of motion communicated by it to any body which stands opposed to it, increases with the quantity of the matter of heat mixed with it.
When without any such change in its external texture, as among Chemists is designated by the word decomposition, a quantity of matter is by the mere intermixture of a quantity of the matter of heat transformed from the liquid into the gaseous, i. e. the indefinitely elastic state, in this case by the mere abstraction of the quantity of heat by which this effect has been produced, it is reconverted to the liquid, i. e. to the definitely elastic state. When, by and during the intermixture of a certain quantity of caloric, it has by the continuance of its unlimited elasticity, been generating and communicating a proportionate quantity of motion, if in a closed receptacle, by the application of a mass of matter in which a less quantity of caloric in a free state, is intermixed, it be divested of its extra quantity of caloric, and thus reduced to its definitely elastic or liquid state, it is then in a condition ready to be, by the same means, as before, converted anew into the gaseous state; and in this state, to be employed in the generation of a quantity of motion, which, if generated under the same circumstances, will be exactly equal to that generated in the first instance: and, in this way, by the alternate conversion and reconversion of the same mass of matter, the alternation between a state of liquidity and a state of gas, between the liquid and the gaseous state, a proportionate quantity of motion may for any length of time be generated.
If, in the form of a parallelopiped, or that of a cylinder, (the most commodious, on several accounts, is that of a cylinder,) the receptacle in which the liquid (say, as being cheapest, the water) is thus converted into the gaseous, and reconverted into the liquid state, be kept to such a degree close, as that no portion of it, either while in the liquid or while in the gaseous state, can make its escape, at the same time that a mass of solid matter, one of the boundaries of which forms one of the boundaries of this receptacle, is as free to move in any direction backwards and forwards, (the most convenient is the vertical, because in that case after the occasionally generated motion, generated by elasticity, has been expended, the constantly existing force of gravity suffices to produce a correspondent quantity of motion.* )
If, of the mass of matter, while in the gaseous state, any portion make its escape, the larger the quantity which thus escapes, the larger the quantity of indefinitely elastic matter which, expending its motion upon bodies other than those to which it is intended that the motion should be communicated, is thus expended in waste.†
The system of machinery in and by which motion derived from this source is employed, is called the Steam-Engine. Steam being the name by which water (till comparatively of late years, the only species of matter which was clearly seen to be alternately interconvertible for any length of time from the liquid into the gaseous form, and vice versá) was alone in its gaseous form designated.
Primum Mobile, in this case, the water while operating in its gaseous or indefinitely elastic state. Secundum Mobile, the mass of solid matter (called, in the steam-engine, the piston) to which the force thus continually generated is communicated.
Some thirty or forty years ago a source of motion, which may be considered as analogous in some respects to the barometrical, and in others to the parallactic source, presented itself to the imagination of the writer of these pages. An instrument by which application was made of it might be styled the Flash-Pump or Rarefaction-Pump.
Compared with the steam-engine, it has the advantage of being capable of being so employed as to generate within a given time, and, as it were, by one stroke, a much greater quantity of motion than within the same time, and at one stroke, could be raised by any steam-engine. But whether the advantage thus gained could, by any circumstances, be rendered such as to overbalance or balance the advantage possessed by the steam-engine in the article of quickness of reciprocation, is a question, the answer to which must be left to any person whose positive knowledge of the subject may dispose him, whilst it qualifies him, to make the requisite calculations.
The principle may be thus explained. Out of a hollow cylinder open at both ends, and in a vertical position stationed in an open reservoir of water, a portion of the air being driven out by the sudden application of heat in a manner analogous to that employed in the Montgolfier or rarefied air balloon, a correspondent portion of the water being thus made to rise and occupy its place, may, by running out, perform the office of a primum mobile.
For speediness of combustion a match composed of tubes open at both ends, such as would be afforded by reeds or straws, the longer the better, cut at each end close to the knot, and, after being dipped in a solution of nitre, would, whatsoever may be the case in regard to economy, at least be as well suited as any others which the nature of the case could furnish. Matters must be so ordered, as that, when the rarefication thus produced by the combustion of this match has attained its maximum, a cover shall apply itself to the top of the cylinder: and the more the degree of closeness wants of that perfection, for the designation of which the name of hermetical is wont to be employed, the less, of course, will be the rarity of the included air, and the less the quantity of water raised by the pressure of the air on the water of the reservoir. Matters must likewise be so ordered, as that, when the height of the column of water thus raised has attained its maximum, it shall be prevented from sinking through the same channel through which it rose, and shall, by this means, be forced to fall in the direction in which, while falling it will perform the function of a primum mobile.
To give continuance to the effect, matters would require, to be so ordered, as that, as soon as the effect produced by the first match has ceased, a second shall take its place; and so on: and, for the accension of each match, the place of human reason might be supplied by some one or other of the expeditious modes of accension already in use. While that part of the water which is performing the function of a primum mobile, is for that purpose descending gradually, a partition sliding horizontally must separate it from that part which is to descend suddenly to make room for the reascent.*
Compared with any which is employed in the steam-engine, the species of fuel would, of course, be in a very high degree, more expensive; whether by the superiority of the quantity of water thus raised by a given weight of the fuel, that inferiority would be counterbalanced, is another point which must be left to calculation in the hands of any person in whose eyes the labour may present itself as capable of yielding a compensation.
If, upon calculation, this source of motion should, in inexperienced hands, be found to afford no promise of being in comparison of the steam-engine, capable, in any situation, of being employed to advantage, it will in this respect, stand upon a footing with the Barometrical source, the Magnetic source, and the Electric and Galvanic sources.
Aplosyncrotic, or Simple-Explosion source.
When not without decomposition, the conversion from the non-gaseous into the gaseous state is effected, reconversion cannot, by the abstraction of the extra quantity of caloric, as above, be made to take place.
By the art of the Chemist, bodies in great variety have been discovered, in the instance of which, they being, all of them, in the solid state, by the application of a certain quantity of caloric, accumulated for the moment, in a portion of matter, be it ever so small, the whole mass, be it ever so large, is with an almost instantaneous rapidity, converted from the solid, without passing into the liquid, into the gaseous state, and thereby a quantity of motion generated, proportioned to the quality and quantity of the matter in the mass thus suddenly transformed, and capable of being employed in the generation of motion, as in the steam-engine, closed or open, as above.
Of these compounds, the one most known, and that which being, in respect of cheapness, most advantageous, or the only one thus employed in general practice, is gunpowder.
In this way, viz. in the case where, antecedently to the gassification, the matter in question is not in the liquid but in the solid state, by the gassification of a given quantity of matter, a much greater degree of elasticity, and in this way a much greater quantity of motion can, in a given space of time, be produced, than by the conversion of a quantity of matter without decomposition from the liquid into the gaseous state.
But, forasmuch as in this way, instead of being employed an indefinite number of times, the mass of matter thus employed in the generation of motion cannot be made to serve more times than one, hence in cases in which, in one and the same receptacle, the generation of motion is required to be kept up without interruption for a constancy, and for an indefinite length of time, this mode of simple explosion cannot be employed with advantage.
In the cases in which it is employed, such as that of the destruction of solid bodies, dead or living, at great distances, the preservation of the gassified matter not being possible, and the quantity of motion producible by a given quantity of it, being so much greater than could, by the gassification of the same quantity of water, be produced by a steam-engine, hence it is, that to these destructive purposes, the costly matter, gunpowder, and not the cheaper matter, water, and coal for heating it, are employed.
In the case where, in a ship of war endeavouring to escape from an enemy’s ship, stern-chase guns are fired, over and above the principal effect, the taking the chance for impeding the advance of the enemy’s ship by damage to the ship and crew, some advantage is said to be obtained in the shape of acceleration given to the course of the ship from which these guns are fired.
Some fifty years ago, or more, a person of the name of Moore, a linen-draper in Fleet Street or Cheapside, formed a plan for giving motion, upon this same principle, to a carriage by land. By the description of a carriage which was to go without horses, under which was to be understood the going without the application of muscular force, the particular means proposed to be employed being kept secret, great expectation was excited, or endeavoured to be excited, as if it were an invention applicable to general use. No trial of it could naturally be made without demonstrating at the same time the possibility of the achievement, and its inapplicability to any generally useful purpose. By persons unacquainted with the general principles of mechanics and chemistry, a matchless degree of velocity was expected, and at length announced to be thus attainable. Wagers, to a considerable amount, were, at the time, said to be laid upon the subject of it. If at any time an actual trial of it were made, the project was, of course, thereby shown to be abortive. Had gunpowder been mentioned as the source trusted to, its inutility would not, to any person tolerably well versed in mechanics and chemistry, have afforded matter for any the smallest doubt. But the nature of the source not being divulged, a man who for this or some other purpose, happened to take a comprehensive view of the whole list of possible sources of motion, would scarcely, on the first mention, have ventured to have pronounced the impossibility of the results declared to be expected.
After the man, the horse, the wind-mill, the water-mill, and the steam-engine, considered with a view to general and extensive use, all other sources of original motion dwindle into insignificance.
Other sources of original motion, however, still remain, which in the way of curiosity, and in a logical view, are necessary to complete the inventory of the distinguishable sources of motion, which, as being known to be in existence or in prospect, present a claim to notice.
Magnetism, Electricity, Galvanism—to one or other of these heads, it is believed, may be referred all the other distinguishable sources of motion with which we are as yet, or have any prospect of becoming acquainted.
In Magnetic attraction may be seen a source of motion, which, of a first view, is not unapt to present the idea of an inexhaustible one. To magnetized iron, power (attractive force) has, and therefore can, at any time be given superior to that of any other motive power which, for a constancy, the muscular power of man is capable of creating: a magnet never tires; and from diuturnity of action, instead of decrease, magnetic power derives increase.
Unfortunately, of any motion derivable from this source, the death is immediate and not less certain than the birth. The contact produced—the contact which it has, in a manner, for its object—all motion is at an end.
For concealing the source of motion, and in that way affording the pleasure of surprise to uninitiated minds, the use of this instrument is well enough known. If motion could for a continuance be produced by it, no source of motion could be so economical a one: but of this there are unhappily no hopes.
Contrivances, whereby to the same magnetized bar a number of plates might be presented in a circularly recurring succession, are sufficiently obvious; and that in such manner that contact never taking place between the bar and any of these plates, the magnetic appetite might still remain unsatisfied. A brass wheel, for instance, in a vertical position, turning on a fixed axis, is, say at the end of each spoke, furnished with an iron plate; up to this wheel, on a plane forming a tangent to the circumference of the wheel, a magnetized bar is slid till it arrives at the spot at which the attraction between itself and one of the plates rising from the wheel, in a position exactly vertical, becomes perceptible. By being fixed to the wheel, this plate is prevented from coming in contact with the bar, and thus satisfying the magnetic appetite. If by the action of the bar upon the plate first presented to it, the wheel with the plate on it could be brought so far round, as, after coming a proportionate way under the bar, to present to it a second plate, and so on, the circuit would thus be completed; and if once completed, would, by the operation of the same causes, be continually renewed, and thus the problem of the perpetual motion would be accomplished. Unfortunately, between the action of the magnet on the second presented plate, in a direction tending to continue the revolution of the wheel and its action on the first presented plate, after its descent, in a direction tending to prevent such continuance, an equilibrium would, at some point or other in the circle, take place; and at that point the revolution would stop.
For the prevention of this catastrophe, to a mind better furnished with practical mechanical experience than with sound theory, the resources of mechanic art might suggest a variety of expedients,* of which the insufficiency would, it is believed, be proved by experiment in each instance. But the nature of things would, it is believed, be inexorable. The track of the subject is not, however, to such a degree beaten, but that, in any institutional work on the subject of mechanics, a demonstration on this ground might, it is supposed, have its use.
That the list may not be justly accused of being an imperfect one, this source of motion must be inserted in it. But compared with those that have been already mentioned, its radical inutility will be altogether obvious.
Of those which appertain to the cognizance of the Chemist, no decomposition, composition, or recomposition, can have taken place but motion must have been produced. But in all those cases the quantity of motion is at the source, by much too small, and confined within too narrow limits to be capable of being communicated to any exterior body, in such sort as to be productive of any serviceable or even so much as sensible effects.
In so far indeed as, in virtue of any such decomposition or composition, any change of matter from a solid or a liquid state into a gaseous state has place, motion in a sensible degree is produced: but, in so far, what has place in this way comes under a head already brought to view, viz., that of the aplosyncrotic source.
Similar in this respect to the magnetic, the electric attraction extends over a space not limited, as in the case of chemical attraction, between particle and particle of a mass in the liquid state, by the sphere of attraction of cohesion. It is even, as in the case of thunder and lightning, capable of operating in the character of a source of motion with great force and through a great extent of space.
Unfortunately, in as far as it is under command, the quantity of motion derivable from this source is by far too small to be in comparison of any of those ordinary sources above-mentioned, of any the smallest use; and when the quantity of motion produced by it is considerable enough to be put to use, were it but under command, it is altogether incapable of being put under command; and by this dilemma, it is completely withdrawn from use.
By the same consideration by which the obligation of inserting in the character of sources of motion the Electric power, the like obligation in relation to the Galvanic is created.
Already by application made of the species of physical power thus denominated has been produced a motion of long continuance, a motion which presents the idea of, and falls little if any short of, the character of a perpetual one. Though in a perpetuity so curious, and in that respect so desirable, a solution of continuity seems liable to be ever and anon produced by an untoward state of the atmosphere.
But by the irreversible laws of nature, the utmost that in the case of generating motion can be done by application of that species of power, is, in comparison with what can be done by motion derived from the ordinary sources, so completely in miniature, that all the achievements capable of being performed by power of this description, seems irrevocably doomed to be confined within the field of curiosity without ever extending themselves over any part of the field of use.
In one laboratory, twenty thousand Galvanic dishes have been, it is said, and probably at this moment are at work; and for a fruit, and at the same time a proof of their labours, a peal of bells kept ringing by them. But scarcely by a hundred times as many, could the sum of their action be brought to bear upon one point,—could any quantity of motion applicable to any purpose of vulgar use be produced.
Antactive, or rcactive source: the source of the application of which the use of springs furnishes an example.
In some instances when, in consequence of external pressure applied to it by another body, a portion more or less considerable of the whole mass of a body has been forced into a portion of space different from that which, antecedently to such pressure, was occupied by it, (the remaining part continuing fixed,) the part that was so removed returns into its antecedent position; in as far as this restitution has place, the body is said to be an elastic body, and a correspondent fictitious entity, a property, a quality—the property or quality of elasticity is said to belong to it.
An instrument to which, by appropriate configuration this property has purposely been bestowed, is termed a spring.
A spring may be defined a reservoir of motion. With reference to motion, it performs exactly the office which a reservoir or receptacle of any kind performs with reference to matter.*
A reservoir of any kind—a reservoir, suppose of water—cannot, for any purpose, supply any quantity of matter greater than has been introduced into it: a spring cannot supply any quantity of motion greater than has been introduced into it, viz. by what may be called the pre-active or tensive force.
In general the greatest quantity of matter which, for any purpose, a reservoir can furnish is not quite as great as the greatest quantity of matter—say of water—which, having been introduced to it, has been contained in it at one and the same time: by the attraction of cohesion, a portion more or less considerable is detained by the matter of which the boundaries of the receptacle are composed, and remains in contact with them; in like manner, the greatest quantity of motion which, for any purpose, a spring can furnish is probably not quite as great as the quantity of motion, or capacity of motion, which, having been introduced into it, remains in it; by means of the phenomenon for the designation of which, the word friction has been employed, a portion more or less considerable of whatsoever motion had, for the purpose in question, been infused into the spring, has been absorbed, as it were, and destroyed.
To actual motion, the sort of capacity for motion, for producing those perceptible phenomena, for the designation of which the word motion is wont to be employed—in a word, the sort of capacity for motion which is in this way kept in store, may be considered as bearing a relation similar to that which in the case of heat, what is called latent heat bears to sensible heat; it is nothing more than a capacity of affording sensible heat; and the substance with which it is combined, and in which it is, as it were, enclosed and imprisoned, may, in virtue of it, be considered as a reservoir of sensible heat.
The action and efficiency of a spring is produced by, and its efficiency depends upon, and is proportioned to the elasticity of the matter of which it is composed: the extra elasticity, that is, what may be called the repulsion correspondent to the attraction of cohesion; or, for shortness, the repulsion of cohesion; the repulsion by which in correspondency with the antagonizing force, viz. the attraction of cohesion, the texture of the substance is determined.
To introduce, into the substance designed to serve as a spring, the quantity of latent motion desired, some external force is and always must be applied, in such manner as to counteract and overpower the repulsion of cohesion, in virtue of which, at the spot at which the external force is made to act, the particles of the body are kept at a distance from each other. If, upon the removal of their external pressure, no other obstacle being opposed to the action of the repulsion of cohesion, the particles of matter in the spot in question arrange themselves exactly in their former places, and thence at their former distances from each other, the matter of which the spring is made, is restored to a form exactly the same as that in which it was, before the pressure. In this case the body is said to be perfectly elastic. If in any part, after the removal of the pressure, the form of the substance is different from what it was antecedently to the application of the pressure, in as far as the form is thus changed, in so far in the parts in question has a correspondent quantity or degree of the repulsion of cohesion been destroyed. In this case the body is imperfectly elastic; the degree of imperfection being in correspondency with the quantity of the repulsion in question destroyed, and the magnitude of the permanent change, which the form of the body has undergone.
The mode in which the latent motion is introduced into the reservoir, may be either pressure (impulse) or tension (distension.) For pressure, (impulse,) no more than one fixed point is necessary; for tension, two at least are necessary. In the case of the bow and the catapult there are three.
In the case where the latent motion is produced by tension, is it by the repulsion of cohesion alone, or by that and the attraction of cohesion together, that the reaction and consequent reinstatement is produced? Answer. It should seem by the repulsion of cohesion alone. Why? Because, in as far as the distension has place, the particles are removed from one another to a distance at and beyond which the incapacity of the attraction of cohesion to act, might be proved by juxtaposition in an exhausted receiver.
Of whatsoever sort the spring may be, and to the production of whatsoever ultimate effect meant to be applied, it cannot be put to use any further than as, whether by impulse or distension, as above,—a quantity of latent motion has been treasured up in the matter of which it is composed. In as far as any such quantity of latent motion has been injected into it, the spring may be said to be charged. As the spring is put to use, the motion thus treasured up is expended, or, as it were, consumed. The expenditure may be either sudden or gradual. It may be termed sudden when the time occupied in the expenditure is not determinately greater than the time that had been occupied in the infusion of it. If it be gradual, it is so in consequence of the retardation which it experiences from some opposing and gradually yielding counterforce.
The term at which the expenditure or consumption, whether sudden or gradual, is destined to take place, may be either immediately upon the termination of the winding up or other operation by which the motion is infused, and the spring charged,† or any subsequent instant of time: in the former case, the spring may be termed a spring for immediate action; in the other case, a spring for predestinated action.
In the case of the ordinary time-piece, the spring is a spring for immediate action; and the expenditure of the injected latent motion gradual.
When the expenditure is gradual, in the course of it, and before any fresh supply is injected, it may be employed according to the quantity of it, in the production of any effects (quantity consumed by friction deducted) to which the same quantity of original motion could be applied within the field of motion within which the process is confined. Of these effects, the most in use to be produced are the two sorts of clocks termed an Astronomical clock and a Musical clock.
An Astronomical clock is nothing more than an ordinary time-piece applied to the indication of a greater number of points of time, in the same length of time, than in the case of an ordinary clock or watch.
In a Musical clock, a system of tubes being provided, into each of which, the air being drawn at a certain aperture, a particular sound is thereupon emitted, and a constant stream of air being injected into a box (for example by a pair of bellows) in which these tubes terminate, matters are so ordered that, at pre-appointed times, the aperture necessary to produce the intended succession of sounds shall be opened, and, when the quantity of time allotted, in each instance, to the sound in question has elapsed, shall thereupon be instantaneously closed.
In the case when the general expenditure being gradual, as in a time-piece, a particular effect not announced is predestined to be produced at a distant point of time, the purpose in view, howsoever in other respects susceptible of being diversified, consists in the production of surprise. In this case the expenditure applied to this particular purpose may, as well as the general expenditure, be of the gradual kind. But, generally speaking, it is rather a sudden than a gradual expenditure that is the best adapted to this purpose.
Of the sort of machine, in the construction of which the motion produced by the spring being predestinated, is instantaneous, the purpose, and that a very variable and extensive one, is the production of surprise.
Under the denomination of mischief, in some shape or other, may be included the only practical purpose to which a machine of this nature, complicated and expensive as it cannot but be, seems likely to be applied:* and for the prevention of any such mischief, divulgation, antecedent to the attempt, divulgation the more extensive the better, affords the only chance which the nature of the case admits of.
Clocks, it is said, have been made, in the instance of each of which, by means of one winding up, the motion has been continued for a twelvemonth; many a one in which, at a predestined time, a door flew open, disclosing some object or objects in motion, or at rest.
The accusation of some individual guilty or innocent; the announcement, true or false, of some catastrophe, natural or supernatural, past or future, affecting this or that individual class, neighbourhood, or whole nation, written in characters of fire; it is only in semi-barbarous society that a contrivance of this sort could be productive of any permanent bad effect. But by the combustion of a quantity of combustible matter, lodged in the machine for that purpose, a conflagration might be produced in any edifice in which, without due examination of its contents, a case containing a machine of this sort, should have been retained.
Under the name of the Torpedo, for the purpose of maritime warfare, in the war now so happily terminated, the Americans employed, or had it in contemplation to employ, a machine for the producing of subaqueous explosion or conflagration. Of a destructive machine of this sort, a time-piece would naturally be a component part.
At the siege of Troy, had this application of the spring to the production of predestinated effects, at predetermined points of time, been known, a destructive machine of this sort, instead of a party of armed men, would have constituted the stuffing of the Trojan horse.
For the purpose of a security against depredation, predestinated destructive movements have been inserted in receptacles destined for the preservation of articles of value against attempts on the part of depredators; a contrivance, for example, whereby, on the opening of the receptacle by any person who is not in the secret, a loaded pistol is discharged. In this case no demand, it is evident, has place for a time-piece. Of the latent motion, by which the purpose is effected, either the expenditure alone, or first the infusion and thereupon the expenditure is performed by the muscular exertion, by which the aperture of the receptacle is effected or attempted. For such a purpose, the spring would probably be found, in every case, a convenient instrument, though cases may be conceded in which it would not be an absolutely indispensable one.
Upon an estimate, if correctly and completely formed, of the effects of both sorts, beneficial and mischievous, in all shapes, expectable from any eventually destructive machine of this description, the probability seems to be that it is on the side of mischief that the balance would be found; and, on this supposition, it would seem that, besides treating all persons knowingly concerned in the fabrication of any such machine, on the footing of co-delinquents in respect of any mischief eventually produced by it, for the purpose of timely prevention, a lesser penalty might be attached to the mere act of him who knowingly, as above, or with just grounds of suspicion before his eyes, shall have engaged or co-operated in the fabrication of it.
In the case of the ball employed in pastime, the lateral injection or impulse is the operation by which the lateral motion is infused; and the motion is instantaneous. Primum Mobile, in the case in which the bound is produced by a single fall or drop, the ball itself. Secundum Mobile, the earth which thereupon reacts upon it, and drives it up again. Primum Mobile in the case in which it is struck, the instrument with which it is struck; or rather, the Primum Mobile, by which, in action, that instrument is moved: for example, when it is by human will that the stroke is produced, the muscular fibres, by the shortening of which the stroke is made.
In the case of the ball the whole instrument is, in every part, a spring.
When a spring enters into the composition of another instrument, it has either a single fixed point, or a number of fixed points. Of the latent motion when injected, these fixed points may, for the purpose of nomenclature, be considered as the seats, and then we have single-seated springs and double-seated ones, as in the case of the time-piece spring.
In the case of the common lock-spring, it has but one fixed point: impulse is the operation by which, in this case, the latent motion is infused; this species of spring may be called the single-seated spring.
In the case of the archer’s bow, it has two fixed points, both permanent. Distension is the operation by which, in this case, the latent motion is infused.
At the instant preceding that of the expenditure, an additional quantity of latent motion is infused by distension, applied at a third point between the two, and with most advantage exactly in the midway between the two.
Sound is a collateral effect producible, in certain circumstances, by the expenditure of the latent motion of a spring. It results incidentally, and without design, from the use made of an arched bow.
When the spring is applied to the production of musical sounds, this collateral effect becomes the principal one.
In the case of the Jew’s harp and the musical pitchfork, the spring is of the single-seated kind.
Not long ago an instrument was constructed, a species of pianoforte, in which, instead of a string, a pitchfork was allotted to each note. No such instrument having come into use, the experiment must have been an unsuccessful one. The inventor was a musician of the name of Claget.
In the case of the violin, with its different enlargements,—in the case of the harpsichord and the pianoforte,—the spring is of the double-seated kind. The occasional additional tension is effected either by gradual friction, as in the case of the violin, by impulse of a plectrum passing beyond the string, as in the case of the harpsichord, or by a hooked plectrum, drawing the string and letting it go, as in the case of the harp, the lute, and the guitar, or by a hammer striking against it, and not going beyond it, as in the case of the pianoforte.
In the case of the Æolian harp, the office of an impelling plectrum is performed by the wind. All the strings are all of them tuned to the same note, and the succession of notes is left to Æolus, who in such circumstances is unable to produce any other notes than those of which the combination called the common chord is composed.
In an organ, could a stop exhibiting any pleasing variety of intonation be composed by the application of the principle of the Æolian harp? The air, by the escape of which from the common reservoir such note is formed, suppose it to strike against a string tuned to that same note?
The Pedal spring.—By this appellation may be designated the sort of spring by which a continued motion is rendered capable of being produced by the alternating tread of the human foot. The spring is in this case a single-seated one. To the fore end is attached an end of a cord,—by the other end of which motion is given to any system of mechanism to what purpose soever applied. A turning-lathe, diversified according to the infinite diversity of purposes to which this instrument is applicable, presents the application most commonly exemplified. The machine for grinding tools is one of them.
The use of the spring here is only after the fore end of it has been pressed down by the foot by one tread, to bring itself up to its former position, that it may be in readiness, without change of posture, to receive another tread, and so toties quoties.
In the action thus carried on by the foot, the force produced by the muscular action receives, or may occasionally be made to receive, more or less of addition from the attraction of gravity operating on the body.
In the case of the carriage-spring for diminishing jolts, the object is not to treasure up or direct motion, but to destroy the effect of it.
Mode in which this effect is produced.—By being communicated along the substance of the spring, the motion produced by the stereopiptic effect of the attraction of gravity, is as it were impalpably pulverised. The quantity of matter being the same, the motion is divided into as many motioncules as there are particles of matter in a line measuring the altitude of the fall; and throughout the line it is encumbered by the repulsion of cohesion, by the expenditure of the latent motion infused by itself into this spring, as into a ball, as above.
To the aggregate of the exemplifications made, and capable of being made, to practical use, of the instrument of reactive motion called the Spring, the application of the bifurcately exhaustive mode of division may, if the mode should afford a promise of being useful, be made by any student by whom any such promise shall have been desired: and of such a labour the discovery of this or that new and useful application of the instrument might possibly be the fruit. As to the author of these pages, having already travelled in this track to a length sufficient for marking out the course to any such person as may happen to feel inclined to pursue it further, to their industry he leaves it.
It must be for Technology, and not here that the application of the generalisative mode of considering the subject must be reserved.
A source of changes infinitely diversified is the terminal cause which, from British Chemists, received the name of Elective Attraction, an expressive and correctly designative name; in the place of which the appellation affinity has, not only by French Chemists, but to a great degree even by British, been employed.*
Limited as is the field of action belonging to this source, confined within limits not distinguishable from those by which the field of attraction of cohesion is circumscribed,—limited, and that to such a degree as to be manifestly incapable of affording, on any occasion, a quantity of motion large enough to be employed to a mechanical purpose, to any advantage, still in a catalogue all-comprehensive of sources of motion, it is not the less strictly entitled to a place.
To enable it to match with the others, it will require a Greek appellation, eclectic, suppose, or eclectico-spastic, be that name.
XIII. In some instances, when, upon the application of caloric, a body is made to pass out of the solid into the liquid form, in one word, upon its melting, say rather (to distinguish this mode of liquefaction from solution in a body already in the liquid form) on its being smelted, its dimensions are on all sides contracted, and this without any such change in its composition as that which has for its cause the species of attraction called elective attraction, as above. But, without intestine motion in some shape or other, no such change, it is evident, can take place.
Of this motion, the result being that, upon the whole, the particles of the body are nearer than they were before, attraction, and not repulsion, is, it should seem, the head to which it must be referred.* Texigenous, or, for shortness, tictic, present themselves as the names by either of which, if the word (idea) be put into a Greek dress, this source of motion may be designated.
XIV. In some instances the like contraction is the result, when, upon the expulsion or absorption of caloric, the body passes out of the liquid into the solid form. For designating the source of the motion which has place in this case, the appellation Stereosigenous, or Stereotic, might, with corresponding propriety, be employed.
In the opposite direction, viz. expansion, very considerable has been the effect produced by or on the passing of a body out of the liquid into the solid form. On the freezing of an enclosed mass of water, a thick mass of iron, in the form of a bomb-shell, has been burst.—This, for curiosity. Applied to fissures, for the purpose of detaching smaller pieces from the huge masses of stone, so denominated, motion from this source has been employed in practice in the character of an economical substitute to mechanical fissures. Thus much for illustration in this place. But, as repulsion, rather than attraction, seems to be the genus to which this effect properly belongs, it is under that head alone that its proper place will be to be found.
The most copious and efficient of all sources from which it is in the power of man to derive any quantity of motion, for which he has a demand, is that which has place, when in the instance of water, a mass of water is made to pass out of the liquid into the gaseous or pneumatic state. In the word pneumatic, or rather pneumatistic, we have, accordingly, an epithet by which this source of motion may be designated. But repulsion and not attraction is the genus to which, in this as in the last-mentioned case, the source of motion here in question seems properly to belong.
When once, by the passing of a body out of the liquid into the gaseous state, in a confined space, a quantity of motion has been generated, a correspondent and equal quantity of motion may be generated, if, in the same confined space, the same mass may be made to pass back again out of the gaseous into the liquid state. If, for designating the source of the motion which has place in the case last mentioned the term pneumatistic be employed, for the designation of that which has place in this present case, some such term as anapneumatistic or catapneumatistic might be employed.
But, to the head or genus here in question, viz. attraction, neither can this source, any more than that other, be referred. But for the motion which immediately precedes this recurrent motion would not have place; and when it does take place, it is not in any local and intestine attraction, but only in the cessation of the intestine repulsion, and the consequent sole dominion of the universally acting attraction—the attraction of gravity, that it has its nominal cause.
To no one body or assemblage of bodies can change of any sort take place, but in some mass of matter or other, in some direction or other, motion must take place. In the case of vegetation those changes take place, by which a small seed is converted into a lofty tree. Narrow as is the field of these motions at each given instant, yet, by means of them, effects have been produced similar to, and not less than those already spoken of, as producible by the conversion of a mass of water from the liquid into the solid state. By the progress of a mass of matter, with the requisite accessions, from the state of the small seed into the state of the tree, fissures and separations have been made, not only in artificial masses of solid matter called walls, but in the natural ones called rocks.
Of the motion thus produced it seems difficult, if not impossible, to say in what proportion, if in any, it has attraction, and in what, if in any, it has repulsion for its nominal source or nominal cause.
To whichsoever of these two heads the cause here in question may be deemed to belong, or phytobiogenous, emphyteutic, present themselves as names, by the one or the other of which it may be designated.
Thus much as to that species of life which is considered and spoken of as having place in the case of vegetation.
Over and above these motions, of which so many exertions of the faculty of the will are the continually and universally experienced sources, there are others, viz. those on which the continuance of life more immediately and essentially depends, in the production of which the will bears no part.
In this case it seems altogether as difficult, if not impracticable as in any of the preceding ones, to say in what proportion, if in any, to attraction, and in what, if in any, to repulsion, the motions which in such infinite variety, as well as profound obscurity, have place, are referable. Whether it be referable to the one, to the other, or to both, epizoic or zoobiogenous present two adjective denominations, by the one or the other, or by both of which, it may, for the purpose of matching with emphyteutic or phytobiogenous, be designated. With the nominal source above designated by the term eclectico-spastic, or elective attraction, a source productive of effects so conspicuously different can scarcely be considered as identical; but to that source it seems to bear a closer analogy than to any others that have been, or to any that remain to be, brought to view.
Magnum rectigal est parsimonia,—Economy is itself a great revenue,—was the saying of a Roman monarch, whose principles in this respect might, with so much advantage to subjects, be adopted by so many other sovereigns.
To motion, considered as a source of mechanic power,—to motion, applied to the humble purposes of mechanics, it may be applied with no less propriety than to the purposes of government.
In this way, in several instances, it has been known to be applied; and the ulterior instances in which it is capable of being applied with advantage, but in which, for want of being present to the mind, it has failed of being applied, are, in number and variety, believed not to be inconsiderable.
It consists in watching for and applying to use all such quantity of motion, and all capacity for affording motion, as within the reach of the person in question, (afforded, either by the spontaneously exerted powers of nature, or by human industry, in the case where, in pursuit of other objects, it is occupied in giving direction to the powers of nature,) is obtainable from any of the original sources above brought to view. In it may accordingly be seen,—in the field of possibility, though not in the field of actual use,—a branch corresponding to each one of all these several original sources.
By that source of motion which is afforded by the attraction of gravity, is afforded, as will soon be seen, the most considerable part of the field in which economy can be employed in this shape.
On a slight glance at the several classes on that list, it will be evident that the Stereopiptic, the Hydropiptic, and the Thelematic, are the only ones from which, under the head of this source of motion, unless the Selenio should be considered as an exemplification of it, any considerable portion of practical use promises ever to be derived.
Of the uses derivable in this shape from falling water and from wind, every one is sufficiently aware.
Of an occasional use capable of being made of the Stereopiptic source, the following mementos may afford an exemplification:—
1. When from a quarry of any kind, situated on an eminence, you are conveying its contents, if circumstances be favourable, so order matters that, whatsoever sort of carriage is employed, the descent of one carriage, when loaded, shall, without the employment of any other force, produce the ascent of an empty or less loaded one.
For this purpose, all you have to do is to fix in the middle of the breadth of the road a post or a series of posts, furnished with horizontal pulleys, at the elevation of the line of draught. In these pulleys plays a rope, attached at one end to the front of the empty carriage, which is to be drawn up hill, and the other end to the back of the loaded carriage, which, by the force of gravity, is to be suffered to run down hill.
When circumstances admit, this expedient, it is believed, is in common, though probably not in universal, use.
2. When, up one and the same ascent, you have occasion to cause to be drawn a loaded carriage, such a number of times that the saving of labour made in this way will be sufficient to compensate the quantity of labour, and wear and tear of the materials necessary to the construction of an apparatus similar to the above, instead of setting your man or men, beast or beasts of draught, to walk up the slope, set them to walk down it; whereupon, by means of the rope playing on the pulley as they descend, the loaded carriage will ascend. In this way the weight will be acting in cooperation with, instead of opposition to, the muscular force employed.
In a mine one bucket is, doubtless, commonly on the above principle, employed in the drawing up an unloaded or less loaded one.*
Supposing any the least attention applied to the establishing of a balance between the descending and the ascending weights, a loaded carriage could, in this way, be conveyed up a declivity, beyond comparison steeper than any up which it would be possible for animals of draught to draw a carriage, even in an unloaded state.
3. When for any economical purpose, within a limited space, such as that of a mine, a manufactory, or ship, or an edifice during the process of erection, men are in the habit of ascending and descending, and at the same time of carrying to the superior level masses of considerable weight, the weight of whatsoever persons or things have to descend may, in the same way, be employed to advantage: the weight to be raised being by means of a rope, moving on a pulley, fixed above the highest point, up to which it is proposed to convey any weight: and the saving thus produced in the article of labour, will be equal to the labour of conveying to the superior spot in question, in each instance, a quantity of matter equal in weight to that the descent of which is connected with the ascent of the antagonizing mass; deducting that which corresponds to the quantity lost by friction.
Analagous to this is the expedient of saving, for the purpose of thus serving in the aggregate, in the character of a primum mobile, portions of water too minute to be separately applicable to any serviceable purpose. They are conducted into a bucket, which, when a quantity sufficient for the purpose has been received into it, descends, and, in its descent, raises an empty one.
The several known Sources of Motion exhibited in systematic order, in the bifurcate and exhaustive mode of division and arrangement.
The remaining task consists in the ranging these several distinguishable sources of motion in systematic order, in such sort that it may be seen in what particulars they respectively agree, and in what particulars they differ.
Archaic or original, and Antactic or non-original.—Applied to the word designative of source, the adjunct original disaffirms the generation of motion from any other source as a necessary condition: by the adjunct antastic or reactive it is affirmed; and from whatsoever original source the original first motion be derived, the antastic is equally capable of manifesting itself. Being exemplified in the sort of instrument or mechanical power called in English a Spring, the antastic or reactive source of motion may also be termed the Spring source.
Purely Physical or Physiurgic; purely Psychical or Thelematic; and mixed Physico-psychical, Anthropophysiurgic or Psychothelematic. Under one or other of these heads will all original sources of motion, it is believed, be found to be comprehended.
Geogenous, Esoteric, or Indigenous; and Exogenous, or Exoteric; indigenous with reference to the earth, the planet in which the motion in question is produced. To the head of Exogenous (Exoteric,) belongs the source above designated by the name of Selenic or Lunar.
In respect of texture, as depending upon, and constituted by, the result of the conflict betwixt or amongst the principles of internal attraction and repulsion, all matter to which we have access, as far as we are able to judge, is at all times in one or other of these states: viz. 1. the solid; 2. the liquid; 3. the gaseous state; and the liquid and the gaseous states are included under one common denomination, viz. the fluid state.
To each of these three states corresponds a natural (purely physical) source of motion: to the solid state, the Stereopiptic; to the liquid, the Hydropiptic; to the gaseous, the Aerogenous. In as far as it is set at work simply by the hand of nature, without assistance or direction given by the hand of man, it may, to distinguish it from the case in which the hand of man is occupied in the giving birth or direction to it, be termed æropnutic, i. e. a source of motion afforded by the wind.
Delo-diathetic or Phanero-diathetic; and Crypto-diathetic. Under one or other of these appellatives may every source of motion, which belongs to the Psychico-physical class, be designated. Under the head of Delo-diathetic or Phancro-diathetic, may be arranged those sources of motion which are produced by the powers of human invention, under the direction of human will, operating upon any one or more of the natural sources of motion above enumerated: in all which cases the motion is the result of those powers with which, at all times, and in his rudest state, man has been familiarly acquainted: viz. the powers corresponding to the different states, in all of which, as above, all matter is apt to place itself, or found capable of being placed.
Of that same Psychico-physical class of sources of motion, under the Crypturgic or Crypto-diathetic branch, are here arranged those sources of motion which correspond to so many different powers or sources of motion with which, in comparison with that which we have with those others, our acquaintance is of recent date, and, in respect of extent and clearness of comprehension, is still comparatively imperfect. Of these, the list will presently be brought to view. There are—1. The Magnetic or Magnetico-spastic. 2. The Electric or Electrico-spastic. 3. The Galvanic or Galvanico-spastic.
In this case, the source from which the division is drawn is not any property belonging to the objects themselves, but the relations which the present state of our own power bear to them respectively.
On this occasion the natural philosopher, in his character of chemist employed in the service of the mechanician, is glad to have recourse to the same shift as that which, in the instance of the class Cryptogamia, was employed by the natural philosopher, acting in the character of botanist,—making the most of everything, and deriving profit to science, in some sort, even from his own ignorance.
In the case in which the Crypto-diathetic branch of the Psychico-physical branch of the sources of motion is employed, the state in which the matter or matters in question is employed in the character in question, viz. that of a source of motion, is either a state in which at the time, during which they are put in action, they had already been placed by the hand of Nature: or a state in which, for the purpose, they are placed by the hand of Art: in the first case, is that source of motion for the designation of which the appellation of Barometrical is here employed: in the other, are the two sources of motion for the designation of which the two appellations Parallactico-suncrotic and Aplo-suncrotic are here employed. Parallactico-syncrotic, when, as in the instance of the water, which, in the case of the steam-engine, is the primum mobile employed,—to produce the effect ultimately desired, it is necessary that the same portion of matter should, a number of times successively, pass alteruately from the liquid to the gaseous state, and vice versâ: aplo-syncrotic, when to produce the alternate effect ultimately desired, no more than one such transition, viz. that from the liquid to the gaseous state, is necessary: which transition is all that the nature of the species of matter in question admits of.
In the first case, for the purpose of their being placed in, and forming part of, a systematic sketch, Ametamorphotic; in the other case, Metamorphotic, is the appellation by which these several branches of the Psychico-physical division of the aggregate system of sources of motion may be designated.
1. The magnetic or magnetico-spastic; 2. the electric or electrico-spastic; 3. the galvanic or galvanico-spastic:—these, of each of which an explanation has been given above, may be considered as so many sources comprehended under the class for the designation of which the terms Crypturgic and Cryptodiathetic have been employed: itself, as above, a branch of the psychico-physical class.
These last, and themselves undivided classes or sources, three in number, are placed upon a one line as they present themselves without any attempt to apply to them the bifurcate mode of division. Their relations to one another are as yet too little understood to admit of their being thus put under subjection by the arranging hand.
As to that source of motion which, under the name of the Economistic, has been brought to view, by the account which on that same occasion was given of it, it is represented as not to be in itself a distinct one; distinct from all or any of the others. It cannot, therefore, without impropriety, be brought under any such plan of division as the one here attempted to be exemplified. But the task of bringing it to view, for which purpose it was necessary that a distinct name should be given to it, presenting itself as one that might be productive of practical advantage, it is therefore, in the character of an appendage, placed at the end of the list of the distinguishable sources of motion, on which the bifurcate and exhaustive mode of division has here been, in the least imperfect manner which the power of the workman admitted of, exemplified.
By the above arrangements, the conception formed of the matters contained in them was in the author’s own instance facilitated, and, as it seemed to him, clarified; in as far as in the instance of any other minds the like good effects shall have been produced, payment for the labour thus expended will have been made.
Detecting, and, if practicable, remedying the imperfections from which it was not in the author’s power, at least with the quantity of time which he could afford to allow to the task, to clear it, might afford an exercise, and, it is imagined, one not altogether unuseful, to the juvenile vigour of the studious mind.
If from the labour thus bestowed in this field, any fruit should come to be reaped by any other mind, it may be referred to the improvement made upon an attempt to exhibit, in the form of a systematic tree, such as is here subjoined,* the arrangement made in his Hermes, by James Harris, of the grammatical parts of speech, and of the view thereby taken of the delusions into which, by his devotion to the ancients, the author, with all his ingenuity, was on that occasion found to have been led.†
On this ulterior subject, a few loose hints are all that the writer can at present afford,—all that he can hope to find the readers, to whom he looks, disposed, on this occasion, to bestow any further portion of their notice.
To reduce to one and the same expression the description of the several sorts of instruments, which are in use to be included under the common name of the mechanical powers, seems to have been an object of desire, and, in some respects, of endeavour, with the authors of institutional works.
In any such desire, in any such endeavour, at least the notion of the practicability of the work is included.
That it may be practicable to reduce to a single expression some certain property, or certain properties common to all these several instruments, is a proposition which I see no reason, nor feel any disposition, to dispute.
But it is only in respect of the uses which they are capable of being put to, that for any purpose but that of barren speculation and solitary amusement or curiosity, they have any of them any claim to the attention of the ingenious, or any other part of mankind.
Now, howsoever it may be in regard to this or that speculative property, in regard to the practical applications made of them—those applications in respect of which alone they can lay any claim to the property of being of use—in reference solely to this property, what may be asserted with confidence is—that they are not capable of being reduced to any such common denomination.
Instruments for gaining force, at the expense of velocity, or velocity at the expense of force, were this a property belonging to all of them, the problem of reducing to one expression the advantage gained by them, might be a not unsolvable one. But out of the six or seven, it is to three only that this common property can justly be ascribed, viz. the lever, the axis in peritrochio, and the pulley or combination of pulleys: to the inclined plane, the screw, and the wedge, it is not applicable. In all these instances, the use derived from the instrument in practice depends upon other sources: upon properties in which the three before-mentioned powers do not any of them partake.
In the case of the lever, the axis in peritrochio and the pulley, the power of the machine finds not an assistance, but, in so far as it operates an impediment; whereas, in the case of the screw and the wedge, were it not for the power of friction, the effect aimed at would not, generally speaking, be produced.
Of the screw, though it certainly may be and actually is employed as well as the lever, axis in peritrochio, and pulley in the raising of weights, yet, the use to which it is applied with much greater frequency, and with a correspondent amount of advantage is that of connexion: binding for an infinity of different purposes, two or more masses of matter in a solid form into one.
So again the inclined plane. It is not for gaining force at the expense of velocity or velocity at the expense of force, that the instrument thus denominated is commonly, if ever, applied: it is for modifying direction; it is for producing in a certain direction certain results, which but for this instrument could not, in certain circumstances, by all the force obtainable by any of these instruments, be obtained.
Suppose a natural rock, or an artificial erection, having for its altitude that of one of the Egyptian pyramids, and for the boundaries of its upper surface, as well of those of its under surface, those of that same pyramid. By the application of force on one side of the paralleli-pedon with all the levers, wheels, and pulleys that could be collected, a man would not communicate the power of either himself mounting to the top of it, or causing a block of stone so to do. Applying an inclined plane to it, making an angle coinciding with any one of the angles made with its base, and the plane at the vertex of the pyramid by one of its present sides, the man may mount upon it, or the block of stone may be drawn up to it.
On this head the theoretical conclusion is, that in pursuing without sufficient scrutiny, and hence with too undeviating an adherence, the path chalked out by the ancients, and by them pointed out by the collective appellation of the mechanical powers,—the five or the six mechanical powers,—the progress of science has in this part of the field, as in so many others, been retarded.
So much for the theoretical conclusion: and the practical which corresponds to it, and is deduced from it, is, that some other principle of arrangement should be looked out for, and that a more comprehensive one—a principle which will afford an opportunity of placing upon the list many species of instruments which, though actually invented and in use, are not as yet put upon the list; many instruments actually known, and known to be in use, and, peradventure, other instruments which by a more correct and complete conception of the subject may continually be brought to light. What is the principle? It consists in substituting to the present arrangement, an arrangement which shall bear reference to the several distinguishable purposes or uses, for which mechanical contrivance is in demand; in one word, in substituting the idea of uses to that of powers. Gaining force at the expense of velocity,—gaining velocity at the expense of force,—are but two of those purposes,—are but two items in an indefinitely, in an hitherto indeterminately ample catalogue; changing direction is a third; forming connexion is a fourth; dissolving connexion is a fifth; and so on. But here, on pain of losing myself altogether in a field foreign to the present purpose, I must make an end.
In the history of the generation and extinction of the birth and death of motion, is involved the question of perpetual motion.
One species of motion there is, which, as far as we can judge, may, with good reason, be pronounced perpetual. It is that by which the bodies which compose the perceptible part of the universe, are kept whirling in their orbits. Perpetual, as far as we can judge, it must be presumed to be. Why? Because there can be discerned no cause, the operation of which should tend to make it cease. This, however, supposes the spaces in which they respectively move to be so many vacuums: for suppose them occupied with matter in any shape,—in the shape of a gas how rare soever,—in the resistance opposed by friction, by the gaseous repulsion of the particles of which it is composed, in that resistance, how distant soever the term may be, may be seen a cause fully adequate to the production of its effect.
In the instance of the stereopiptic source, numerous, it is believed, have been the contrivances produced by the hope of converting a source of short-lived motion into a perpetual one.
One consisted of a wheel, in which, along a spiral channel, a quantity of mercury was to find its way in its fall from the axis to the circumference; the longer the semi-diameter of the wheel, the longer the lever with which, when arrived at the circumference, the mass of mercury would act upon any body situated nearer to the centre. Make the diameter of your wheel infinite, and the force you will thus acquire will be the half of an infinite force. But, long before you had been at the trouble of giving to it any such inconvenient extent, you would have acquired force enough to pump up into the annular reservoir contiguous to the axle-tree a supply of mercury sufficient to continue the motion, and thus your motion would be a perpetual one. Somewhat in this strain seems to have been the reasoning that gave birth to this contrivance.
By the time it had reached the circumference, subtraction made of the force destroyed by friction, the mercury would have produced an effect equal to the effect produced by the same mass of mercury in falling from its position near the axis to its position near the circumference, without the trouble of taking any such sweep.
In the course of its transit from the one end of the spiral to the other, it would have to make a number of descents, as also a number of ascents, proportioned to the number of convolutions or threads in the spiral: the descents would be so many motions having for their adequate cause the attraction of gravity; the ascents would be so many motions, none of which would have any adequate cause; friction sufficing of itself to prevent the cause which in the preceding descent they respectively had from being an adequate one.
All perpetual motions having for their source the attraction of gravity, would, it is believed, be found resolvable into this mercurial one.
Some five and forty years ago, Dr Kenrick, most known by an attack made by him on Dr Johnson the Great, in an 8vo volume entituled Lexiphonis, took in hand the subject of the perpetual motion, and on this subject read, and afterwards published, a few lectures of which the effect, if any, was to render the subject somewhat more obscure than he found it. The object was to render probable the possibility of the existence of this rival of the philosopher’s stone. One of the proofs consisted in some mention that was made of a certain mysterious wheel invented and manufactured by a person of the name of Orphyonis. By this wheel great were the wonders wrought; but, unhappily, the instrument being with prudent caution kept constantly enclosed in an opaque and well-locked box, the invention died with the inventor, and was thus lost for ever to the world.
Not being known to the world by any other work, the inventor, Orphyonis, has somewhat the air of having been in the way of eponthesis, derived from Orpheus.
If any such wheel was ever made, it may be affirmed, without much danger of mistake, that the principle upon which it was constructed, was either the mercurial principle just explained, or the magnetic, of which the idea has been already given.*
By the perpetual motion is designated a motion, which, how ill-grounded soever, has on various occasions been espoused, by men not altogether unconversant either with the practice or with the principles of mechanics. On this part of the field, one true use of science is to render clear, and hold up to view the delusiveness of all expectations entertained on this ground, and thereby prevent the disappointments and pecuniary losses with which all such expectations can scarcely in the event of their being acted upon fail of being productive.
For any motion of any mass or masses of matter, situated within the reach of human agency, to be in the literal import of the word perpetual, it would require that the masses of matter in question should be in every part indestructible, and the particles of which they are composed, unsusceptible of being, any one of them, by means of the motion or otherwise, separated from any other. A notion to any such effect being in opposition to universal and continual observation and experience, can scarcely be supposed to have ever found admittance into any human breast.
But, independently of the operation of any such manifestly and universally operating cause, by the word friction as above explained, is moreover designated a cause, in which no imaginable motion, from whichsoever of the above sources proceeding, can fail of experiencing, within a very short space of time, unless renewed, its inevitable death.
But in any case, in which the motion can be said to be renewed, the motion, when the case is more clearly looked into, will be seen not to be one and the same: it is a continually successive creation of fresh motions: viz. in the case of falling water, falling earth, or wind, the motions of fresh and fresh parcels of matter, receiving motion one after another, though in the same direction; in the case of motion produced by muscular exertion, fresh and fresh exertions of the will, and contraction of the same or other muscles, produced in consequence.
If in the import of the words perpetual motion, were included the idea of any internal source of motion, by which different particles of matter, after having in any never-interrupted series been put successively in motion, were so to continue without end, then and in such case there would at all times be as many perpetual motions as there are distinguishable purely physical sources of motion (meaning individual sources, not species of sources) operating and producing motion, as above. But, in no one of the cases, in which a perpetual motion has been said to be invented, or said to be capable of being invented, does any such state of things appear to have been in view.
[* ] The necessity to which we are subjected by the imperfection of the instrument for the purposes of discourse, the necessity of mixing falsehood with truth, on pain of being without ideas, as well as without conversation, on some of the most interesting of the subjects that lie within the pale of our cognizance, is productive but too abundantly of misconception and false reasoning; and this not only in the physical department of the field of thought, discourse, and action, but also in every other. On pain of having some of the most interesting subjects of thought, discourse, and action undiscoursed of, and even unthought of, we set to work the powers of our imaginations in the creation, as it were, of a multitude of imaginary beings, all spoken of as if they belonged to the class of bodies or substances; and on the occasion, and for the purpose of this creation, we attach to them a name or sign, called a part of speech: viz., a species of word, termed a noun substantive; the same species of word as that of which, in the character of a common name, we make use for the designation of real entities, appertaining strictly and properly to the class of substances. Beholding at a distance, in the dress of a man, sitting and playing upon an organ, an automaton figure, constructed for that purpose by the ingenuity of the mechanist, to take this creature of human art for a real man, is a sort of mistake which, at a certain distance, might happen for a time to be made by the most acute observer. In like manner, beholding a part of speech cast in the same mould with the name of a real entity, a really existing substance, no wonder if, on a variety of occasions, to the mental eye of a very acute observer, this fictitious entity thus accoutred, should present itself in the character of, and be regarded and treated as if it were a real one. How should it be otherwise, when on every occasion on which, and by every person by whom it is spoken of at all, it is spoken of as if it were a real entity? and thus in a manner an universal attestation is given to the truth of a set of propositions, the falsity of which when once brought to view, cannot in any instance fail to be recognised.
[* ] The idea of motion is capable of being deduced from difference of position, without any difference of distance, as well as from difference of distance; but being much more complicated, the description of that case is, on that account, omitted.
[† ] See this division discussed at length, under the head of Ontology, in this volume.—Ed.
[‡ ] Not so in every language, in the French, for example, (en repos) rest, is also a receptacle.
[* ] [Selenic.] From a Greek word which signifies the moon.
[† ] [Selenigenous.] From two Greek words; the first of which signifies the moon, the other, originating in, or sprung from.
[‡ ] [Hydropiptic.] From two Greek words, the first of which signifies water, the other falling.
[§ ] [Chemico-mechanical.] Because, in this case, it is only by means of the chemical operations of solution and precipitation that the mechanical power is produced.
[* ] [Stereopiptic.] From two Greek words; the first of which signifies solid; the other, falling, as above.
[† ] By the mere increase of the quantity resting on any given portion of the solid part of the earth’s surface.
[‡ ] [Barometrical.] From the instrument called the Barometer: an appellation derived from two Greek words; the first of which signifies weight, (viz. of the air) and the other a measure, or instrument for measuring. In respect to principles of construction, as in the text, that instrument and the one here described are the same. Only in the case of the Barometer, the object being not to generate motion, but merely to indicate the changes in the height, and consequent weight and pressure, of the column of air superincumbent on the place or portion of space in question at different times, no greater quantity of matter of all kinds is employed than the small quantity necessary for this latter purpose.
[* ] [Thelematic.] From a Greek word, which signifies the will.
[† ] [Myiobrachiatic.] From two Greek words; one of which signifies a set of muscular fibres; the other, shortening.
[* ] This sentence is incomplete: what was meant to be announced was, probably, that by this construction the force generated is economised.—Ed.
[† ] Some thirty or forty years ago, an Hungarian of the name of Kempel, applied to me to consult with me about an invention of his which he regarded as an improvement on the steam-engine. It consisted in the omission of the piston, in such sort, that the steam, as fast as generated, and without being recondensed, should operate immediately, and in the open air, upon the float-boards of a water-wheel: in which case, before it had time to lose all its extra caloric, and with it all its elastic force, some small quantity of motion, though comparatively a very small one, might occasionally be expected to be generated. It might be termed an open steam-engine. Will it be believed? This was the same Kempel by whose inventions of the automaton chess-player, and the automaton speaking-child, the curious were in most parts of Europe so much surprised and gratified.
The chess-player in the character of a Turk was beaten by very few Christians; and I know not whether the contrivance by which the motion was communicated from the directing mind to the chessman was ever divulgated or discovered.
The child, though at the time when I saw it, it had not, by a good deal, gone through the alphabet, yet pronounced a number of intelligible words, in the composition of which consonants as well as vowels were included. To produce the sounds, he worked with both his hands at a time, concealed in a sort of satchel or leather bag.
[* ] For the purpose of this separation, attached to the cylinder, during a sufficient portion of its altitude, may be a hollow paralellepedon of correspondent diameter, one side of it being constituted by the sliding partition in one piece, or as many pieces as may be found most convenient.
[* ] For instance, making the angle made by each plate with the circumference vary at different parts of the round, or the whole plate drop and form a tangent to the circumference of the wheel, instead of standing up at right angles to it.
[* ] To the inhabitants of classical antiquity, the use of springs seems scarcely to have been known. Neither in Latin nor in Greek has any word been found that seems to have been employed in the designation of it.
In any one of the instruments found in any one of the buried cities, is any example of a spring to be found?
[† ] When into an electric jar an extra quantity of electric power has been infused, the jar is said to be charged. By analogy, a spring, when the quantity of latent motion, on which its action depends, has been infused into it, may be said to be charged.
[* ] Alarm-clocks are innoctious and useful applications of this kind.—Ed.
[* ] [Affinity.] Unhappily chosen surely, was this appellation. Instead of being expressive, (so far from being characteristic,) it seems to be not merely inexpressive but misexpressive. 1. In other cases, in the only cases which, when application of it to this purpose was first made, could have been in view, affinity was employed to designate the bond of connexion which has place amongst members of the same family, and, as such, designated by one common name. According to this analogy, all acids, for example, being of the same family, and designated by one common name, it is amongst these that affinity should be said to have place: amongst all these, saline bodies, how great soever may be their number; and so in regard to alkalies; and no as between one acid, or all acids, on one part, and an alkali, or all alkalies, on the other.
2. In this case, for employing the term attraction, the same reason has place as in any of those other cases; by the term, electric attraction, this analogy is expressed. By the term affinity, if the word be used in those other cases, or any of them, it is virtually disaffirmed.
3. By the epithet elective, intimation is given of those preferences: that prodigiously complicated system of preferences, as between element and element, by which this species of relation is so conspicuously distinguished. Of this system, by the word affinity, not any the slightest intimation is conveyed.
[* ] In a still greater degree this contraction takes place in several instances in the case of solution as just explained; but being smelted, what is it but being dissolved in caloric?
[* ] In the case of the streets, for example, which run at right angles between the river Thames and the Strand, if, during a certain part of the twenty-four hours, the exclusive use of the street could be secured to the coal-dealers, by whose carts coals are conveyed from the river to their destination, in the several adjacent streets and roads of the metropolis and its neighbourhood, considerable saving in the article of horses might thus, it is supposed, be made. In the way of apparatus, the rope and pulley excepted, nothing more would be necessary than a line of strong uprights, in number proportioned to the length of the street, each of which, stationed in the middle of its breadth, and turning on a hinge, might, in a direction parallel to its length, be lowered and placed in a horizontal position, on the expiration of the portion of the twenty-four hours allotted to this service.
Of these coal-carts, every one that went up full, would have to come down empty: here, then, would be an occasion in which the draught upwards might have for its assistance, if time could be made to suit, not only the weight of such horses, as belonging to that same carriage had been sent up the declivity for the purpose of drawing it up as they descended, but the weight of an empty and returning carriage, with the horses employed in drawing it.
So in regard to other goods at large, generally speaking, and bating the effect of any particular goods by which the natural equality between the weight of goods exported from, and that of goods imported to, a mass of water used for conveyance, may happen to be disturbed, for every ton of goods conveyed up the declivity, there would be a ton of other goods conveyed down it; and thus to the assistance afforded by the descending carriages would be added that afforded by the descending goods. In this way, then, supposing the circumstances to admit of the requisite agreement, amongst the several proprietors of goods, and other parties interested, calculation would soon show the multitude of horses which might by this means be saved.
In the case where no animal is employed in the draught, it has not unfrequently happened to me to be an eye-witness of the exemplification of this principle of economy. In the case where, in the production of this same effect, animal draught is employed, it has never happened to me to see or hear of any instance of its being put to use in this country. In Russia, in the year 1756, under the direction of my brother, Sir Samuel Bentham, with whom, for anything that either of us know or knew to the contrary, the idea had originated, I saw it put in practice; and it was pleasing to observe in how high a degree, while the quantity of matter conveyed up the declivity was increased, the toil of the horses was diminished.
About the year 1793, I remember his communicating the idea, by word of mouth, to the intelligent and useful servant of the public, Mr Samuel More, then Secretary to the Society of Arts; but I have not heard that, in practice, any application has been ever made of it.
[* ] This tree has not been found among the MSS.
[† ] Viz. the adverb represented as having an import distinct from that of the other parts of speech, and thereby from that of the preposition, that of the noun substantive, and that of the noun or pronoun adjective: whereas, in every case the import of it is resolvable into the several imports of those three parts of speech taken together: take, for example,
[* ] At that time, and for a good many years afterwards, there existed a sort of philosophical club, composed at first of but a small number of members, which, at different periods of its existence went, I believe, by different names, two or more, no one of which is at present in my memory. At that time, the number of its members was small, but antecedently to its extinction, its members, as well as its celebrity, had received considerable increase. Sir Joseph Banks, the late Dr Solander, John Hunter the surgeon, Myln the architect, the still existing and celebrated Mr Richard Lovel Edgeworth, Dr George Fordyce the physician, Jesse Ramsden the optician, Conyers the celebrated watchmaker and writer on that subject, another Conyers, Arabic Professor somewhere in Scotland, and perhaps one or two more members. I had myself, at that time, the honour of being, in this way, an associate of so many ingenious and illustrious men, together with the shame of being a very ignorant and altogether an unprofitable one. Curiosity drew to these lectures of Dr Kenrick several members of that club: two whom I recollect as being of the number, were Mr Edgeworth and the watchmaking Conyers. It was by Dr Fordyce that I was introduced.