Consolations in Travel Part 4

_The Unknown_.--They proved to me, at least, that not merely the oxygen dissolved in water, but likewise a part of the azote, was absorbed in the respiration of this animal.

_Eub_.--So that your researches confirm those of the French savants and Alexander von Humboldt, that in the respiration of animals which separate air from water, both principles of the atmosphere are absorbed.

_Phil_.--I have heard so many and such various opinions on the nature of the function of respiration during my education and since, that I should like to know what is the modern doctrine on this subject. I can hardly refer to better authority than yourself, and I have an additional reason for wis.h.i.+ng for some accurate knowledge on this matter, having, as you well know, been the subject of an experiment in relation to it which, but for your kind and active a.s.sistance, must have terminated fatally.

_The Unknown_.--I shall gladly state what I know, which is very little.

In physics and in chemistry, the science of dead matter, we possess many facts and a few principles or laws; but whenever the functions of life are considered, though the facts are numerous, yet there is, as yet, scarcely any approach to general laws, and we must usually end where we begin by confessing our entire ignorance.

_Eub_.--I will not allow this ignorance to be entire. Something, undoubtedly, has been gained by the knowledge of the circulation of the blood and its aeration in the lungs--these, if not laws, are at least fundamental principles.

_The Unknown_.--I speak only of the functions in their connection with life. We are still ignorant of the source of animal heat, though half a century ago the chemists thought they had proved it was owing to a sort of combustion of the carbon of the blood.

_Phil_.--As we return to our inn I hope you will both be so good as give me your views of the nature of this function, so important to all living things; tell me what you _know_, or what you _believe_, or what others _imagine they know_.

_The Unknown_.--The powers of the organic system depend upon a continued state of change. The waste of the body produced in muscular action, perspiration, and various secretions, is made up for by the constant supply of nutritive matter to the blood by the absorbents, and by the action of the heart the blood is preserved in perpetual motion through every part of the body. In the lungs, or bronchia, the venous blood is exposed to the influence of air and undergoes a remarkable change, being converted into arterial blood. The obvious chemical alteration of the air is sufficiently simple in this process: a certain quant.i.ty of carbon only is added to it, and it receives an addition of heat or vapour; the volumes of elastic fluid inspired and expired (making allowance for change of temperature) are the same, and if ponderable agents only were to be regarded it would appear as if the only use of respiration were to free the blood from a certain quant.i.ty of carbonaceous matter. But it is probable that this is only a secondary object, and that the change produced by respiration upon the blood is of a much more important kind.

Oxygen, in its elastic state, has properties which are very characteristic: it gives out light by compression, which is not certainly known to be the case with any other elastic fluid except those with which oxygen has entered without undergoing combustion; and from the fire it produces in certain processes, and from the manner in which it is separated by positive electricity in the gaseous state from its combinations, it is not easy to avoid the supposition that it contains, besides its ponderable elements, some very subtle matter which is capable of a.s.suming the form of heat and light. My idea is that the common air inspired enters into the venous blood entire, in a state of dissolution, carrying with it its subtle or ethereal part, which in ordinary cases of chemical change is given off; that it expels from the blood carbonic acid gas and azote; and that in the course of the circulation its ethereal part and its ponderable part undergo changes which belong to laws that cannot be considered as chemical--the ethereal part probably producing animal heat and other effects, and the ponderable part contributing to form carbonic acid and other products. The arterial blood is necessary to all the functions of life, and it is no less connected with the irritability of the muscles and the sensibility of the nerves than with the performance of all the secretions.

_Eub_.--No one can be more convinced than I am of the very limited extent of our knowledge in chemical physiology, and when I say that, having been a disciple and friend of Dr. Black, I am still disposed to prefer his ancient view to your new one, I wish merely to induce you to pause and to hear my reasons; they may appear insufficient to you, but I am anxious to explain them. First, then, in all known chemical changes in which oxygen gas is absorbed and carbonic acid gas formed, heat is produced. I could mention a thousand instances, from the combustion of wood or spirits of wine to the fermentation of fruit or the putrefaction of animal matter.

This general fact, which may be almost called a law, is in favour of the view of Dr. Black. Another circ.u.mstance in favour of it is, that those animals which possess the highest temperature consume the greatest quant.i.ty of air, and, under different circ.u.mstances of action and repose, the heat is in great measure proportional to the quant.i.ty of oxygen consumed. Then those animals which absorb the smallest quant.i.ty of air are cold-blooded. Another argument in favour of Dr. Black's opinion is the change of colour of blood from black to red, which seems to show that it loses carbon.

_The Unknown_.--With the highest respect for the memory of Dr. Black, and for the opinion of his disciple, I shall answer the arguments I have just heard. I will not allow any facts or laws from the action of dead matter to apply to living structures; the blood is a living fluid, and of this we are sure that it does not burn in respiration. The terms warmth and cold, as applied to the blood of animals, are improper in the sense in which they have been just used; all animals are, in fact, warm-blooded, and the degrees of their temperature are fitted to the circ.u.mstances under which they live, and those animals, the life of which is most active, possess most heat, which may be the result of general actions, and not a particular effect of respiration. Besides, a distinguished physiologist has rendered it probable that the animal heat depends more upon the functions of the nerves than upon any result of respiration. The argument derived from change of colour is perfectly delusive; it would not follow if carbon were liberated from the blood that it must necessarily become brighter; sulphur combining with charcoal becomes a clear fluid, and a black oxide of copper becomes red in uniting with a substance which abounds in carbon. No change in sensible qualities can ever indicate with precision the nature of chemical change. I shall resume my view, which I cannot be said to have fully developed. When I stated that carbonic acid was formed in the venous blood in the processes of life, I meant merely to say that this blood, in consequence of certain changes, became capable of giving off carbon and oxygen in union with each other, for the moment inorganic matter enters into the composition of living organs it obeys new laws. The action of the gastric juice is chemical, and it will only dissolve dead matters, and it dissolves them when they are in tubes of metal as well as in the stomach, but it has no action upon living matter. Respiration is no more a chemical process than the absorption of chyle; and the changes that take place in the lungs, though they appear so simple, may be very complicated; it is as little philosophical to consider them as a mere combustion of carbon as to consider the formation of muscle from the arterial blood as crystallisation. There can be no doubt that all the powers and agencies of matter are employed in the purposes of organisation, but the phenomena of organisation can no more be referred to chemistry than those of chemistry to mechanics. As oxygen stands in that electrical relation to the other elements of animal matter which has been called electropositive, it may be supposed that some electrical function is exercised by oxygen in the blood; but this is a mere hypothesis. An attempt has been made founded on experiments on the decomposition of bodies by electricity to explain secretion by weak electrical powers, and to suppose the glands electrical organs, and even to imagine the action of the nerves dependent upon electricity; these, like all other notions of the same kind, appear to me very little refined. If electrical effects be the exhibition of certain powers belonging to matter, which is a fair supposition, then no change can take place without their being more or less concerned; but to imagine the presence of electricity to solve phenomena the cause of which is unknown is merely to subst.i.tute one undefined word for another. In some animals electrical organs are found, but then they furnish the artillery of the animal and means of seizing its prey and of its defence. And speculations of this kind must be ranked with those belonging to some of the more superficial followers of the Newtonian philosophy, who explained the properties of animated nature by mechanical powers, and muscular action by the expansion and contraction of elastic bladders; man, in this state of vague philosophical inquiry, was supposed a species of hydraulic machine. And when the pneumatic chemistry was invented, organic structures were soon imagined to be laboratories in which combinations and decompositions produced all the effects of living actions; then muscular contractions were supposed to depend upon explosions like those of the detonating compounds, and the formation of blood from chyle was considered as a pure chemical solution. And, now that the progress of science has opened new and extraordinary views in electricity, these views are not unnaturally applied by speculative reasoners to solve some of the mysterious and recondite phenomena of organised beings. But the a.n.a.logy is too remote and incorrect; the sources of life cannot be grasped by such machinery; to look for them in the powers of electro-chemistry is seeking the living among the dead: that which touches will not be felt, that which sees will not be visible, that which commands sensations will not be their subject.

_Phil_.--I conclude, from what you last said, that though you are inclined to believe that some unknown subtle matter is added to the organised system by respiration, yet you would not have us believe that this is electricity, or that there is any reason to suppose that electricity has a peculiar and special share in producing the functions of life.

_The Unknown_.--I wish to guard you against the adoption of any hypothesis on this recondite and abstruse subject. But however difficult it may be to define the exact nature of respiration, yet the effect of it and its connexions with the functions of the body are sufficiently striking. By the action of air on the blood it is fitted for the purposes of life, and from the moment that animation is marked by sensation or volition, this function is performed, the punctum saliens in the ovum seems to receive as it were the breath of life in the influence of air. In the economy of the reproduction of the species of animals, one of the most important circ.u.mstances is the aeration of the ovum, and when this is not performed, from the blood of the mother as in the mammalia by the placenta, there is a system for aerating as in the oviparous reptiles or fishes, which enables the air freely to pa.s.s through the receptacles in which the eggs are deposited, or the egg itself is aerated out of the body through its coats or sh.e.l.l, and when air is excluded, incubation or artificial heat has no effect. Fishes which deposit their eggs in water that contains only a limited portion of air, make combinations which would seem almost the result of scientific knowledge or reason, though depending upon a more unerring principle, their instinct for preserving their offspring. Those fishes that sp.a.w.n in spring or the beginning of summer and winch inhabit deep and still waters, as the carp, bream, pike, tench, &c., deposit their eggs upon aquatic vegetables, which by the influence of the solar light constantly preserve the water in a state of aeration. The trout, salmon, hucho, and others of the Salmo genus, which sp.a.w.n in the beginning or end of winter, and which inhabit rivers fed by cold and rapid streams which descend from the mountains, deposit their eggs in shallows on heaps of gravel, as near as possible to the source of the stream where the water is fully combined with air; and to accomplish this purpose they travel for hundreds of miles against the current, and leap over cataracts and dams: thus the Salmo salar ascends by the Rhone and the Aar to the glaciers of Switzerland, the hucho by the Danube, the Isar, and the Save, pa.s.sing through the lakes of the Tyrol and Styria to the highest torrents of the Noric and Julian Alps.

_Phil_.--My own experience proves in the strongest manner the immediate connection of sensibility with respiration; all that I can remember in my accident was a certain violent and painful sensation of oppression in the chest, which must have been immediately succeeded by loss of sense.

_Eub_.--I have no doubt that all your suffering was over at the moment you describe; as far as sensibility is concerned, you were inanimate when your friend raised you from the bottom. This distinct connection of sensibility with the absorption of air by the blood is, I think, in favour of the idea advanced by our friend, that some subtle and ethereal matter is supplied to the system in the elastic air which may be the cause of vitality.

_The Unknown_.--Softly, if you please; I must not allow you to mistake my view. I think it probable that some subtle matter is derived from the atmosphere connected with the functions of life; but nothing can be more remote from my opinion than to suppose it the cause of vitality.

_Phil_.--This might have been fully inferred from the whole tenor of your conversation, and particularly from that expression, "that which commands sensation will not be their subject." I think I shall not mistake your views when I say that you do not consider vitality dependent upon any material cause or principle.

_The Unknown_.--You do not. We are entirely ignorant on this subject, and I confess in the utmost humility my ignorance. I know there have been distinguished physiologists who have imagined that by organisation powers not naturally possessed by matter were developed, and that sensibility was a property belonging to some unknown combination of unknown ethereal elements. But such notions appear to me unphilosophical, and the mere subst.i.tution of unknown words for unknown things. I can never believe that any division, or refinement, or subtilisation, or juxtaposition, or arrangement of the particles of matter, can give to them sensibility; or that intelligence can result from combinations of insensate and brute atoms. I can as easily imagine that the planets are moving by their will or design round the sun, or that a cannon ball is reasoning in making its parabolic curve. The materialists have quoted a pa.s.sage of Locke in favour of their doctrine, who seemed to doubt "whether it might not have pleased G.o.d to bestow a power of thinking on matter." But with the highest veneration for this great reasoner, the founder of modern philosophical logic, I think there is little of his usual strength of mind in this doubt. It appears to me that he might as well have asked whether it might not have pleased G.o.d to make a house its own tenant.

_Eub_.--I am not a professed materialist; but I think you treat rather too lightly the modest doubts of Locke on this subject. And without considering me as a partisan, you will, I hope, allow me to state some of the reasons which I have heard good physiologists advance in favour of that opinion to which you are so hostile. In the first accretion of the parts of animated beings they appear almost like the crystallised matter, with the simplest kind of life, scarcely sensitive. The gradual operations by which they acquire new organs and new powers, corresponding to these organs, till they arrive at full maturity, forcibly strikes the mind with the idea that the powers of life reside in the arrangement by which the organs are produced. Then, as there is a gradual increase of power corresponding to the increase of perfection of the organisation, so there is a gradual diminution of it connected with the decay of the body.

As the imbecility of infancy corresponds to the weakness of organisation, so the energy of youth and the power of manhood are marked by its strength; and the feebleness and dotage of old age are in the direct ratio of the decline of the perfection of the organisation, and the mental powers in extreme old age seem destroyed at the same time with the corporeal ones, till the ultimate dissolution of the frame, when the elements are again restored to that dead nature from which they were originally derived. Then, there was a period when the greatest philosopher, statesman, or hero, that ever existed was a mere living atom, an organised form with the sole power of perception; and the combinations that a Newton formed before birth or immediately after cannot be imagined to have possessed the slightest intellectual character. If a peculiar principle be supposed necessary to intelligence, it must exist throughout animated nature. The elephant approaches nearer to man in intellectual power than the oyster does to the elephant; and a link of sensitive nature may be traced from the polypus to the philosopher. Now, in the polypus the sentient principle is divisible, and from one polypus or one earthworm may be formed two or three, all of which become perfect animals, and have perception and volition; therefore, at least, the sentient principle has this property in common with matter, that it is divisible. Then to these difficulties add the dependence of all the higher faculties of the mind upon the state of the brain; remember that not only all the intellectual powers, but even sensibility is destroyed by the pressure of a little blood upon the cerebellum, and the difficulties increase. Call to mind likewise the suspension of animation in cases similar to that of our friend, when there are no signs of life and when animation returns only with the return of organic action. Surely in all these instances everything which you consider as belonging to spirit appears in intimate dependence upon the arrangements and properties of matter.

_The Unknown_.--The arguments you have used are those which are generally employed by physiologists. They have weight in appearance, but not in reality. They prove that a certain perfection of the machinery of the body is essential to the exercise of the powers of the mind, but they do not prove that the machine is the mind. Without the eye there can be no sensations of vision, and without the brain there could be no recollected visible ideas; but neither the optic nerve nor the brain can be considered as the percipient principle--they are but the instruments of a power which has nothing in common with them. What may be said of the nervous system may be applied to a different part of the frame; stop the motion of the heart, and sensibility and life cease, yet the living principle is not in the heart, nor in the arterial blood which it sends to every part of the system. A savage who saw the operation of a number of power-looms weaving stockings cease at once on the stopping of the motion of a wheel, might well imagine that the motive force was in the wheel; he could not divine that it more immediately depended upon the steam, and ultimately upon a fire below a concealed boiler. The philosopher sees the fire which is the cause of the motion of this complicated machinery, so unintelligible to the savage; but both are equally ignorant of the divine fire which is the cause of the mechanism of organised structures. Profoundly ignorant on this subject, all that we can do is to give a history of our own minds. The external world or matter is to us in fact nothing but a heap or cl.u.s.ter of sensations; and, in looking back to the memory of our own being, we find one principle, which may be called the _monad_, or _self_, constantly present, intimately a.s.sociated with a particular cla.s.s of sensations, which we call our own body or organs. These organs are connected with other sensations, and move, as it were, with them in circles of existence, quitting for a time some trains of sensation to return to others; but the monad is always present. We can fix no beginning to its operations; we can place no limit to them. We sometimes, in sleep, lose the beginning and end of a dream, and recollect the middle of it, and one dream has no connection with another; and yet we are conscious of an infinite variety of dreams, and there is a strong a.n.a.logy for believing in an infinity of past existences, which must have had connection; and human life may be regarded as a type of infinite and immortal life, and its succession of sleep and dreams as a type of the changes of death and birth to which from its nature it is liable. That the ideas belonging to the mind were originally gained from those cla.s.ses of sensations called organs it is impossible to deny, as it is impossible to deny that mathematical truths depend upon the signs which express them; but these signs are not themselves the truths, nor are the organs the mind. The whole history of intellect is a history of change according to a certain law; and we retain the memory only of those changes which may be useful to us--the child forgets what happened to it in the womb; the recollections of the infant likewise before two years are soon lost, yet many of the habits acquired in that age are retained through life. The sentient principle gains thoughts by material instruments, and its sensations change as those instruments change; and, in old age, the mind, as it were, falls asleep to awake to a new existence. With its present organisation, the intellect of man is naturally limited and imperfect, but this depends upon its material machinery; and in a higher organised form, it may be imagined to possess infinitely higher powers. Were man to be immortal with his present corporeal frame, this immortality would only belong to the machinery; and with respect to acquisitions of mind, he would virtually die every two or three hundred years--that is to say, a certain quant.i.ty of ideas only could be remembered, and the supposed immortal being would be, with respect to what had happened a thousand years ago, as the adult now is with respect to what happened in the first year of his life. To attempt to reason upon the manner in which the organs are connected with sensation would be useless; the nerves and brain have some immediate relation to these vital functions, but how they act it is impossible to say. From the rapidity and infinite variety of the phenomena of perception, it seems extremely probable that there must be in the brain and nerves matter of a nature far more subtle and refined than anything discovered in them by observation and experiment, and that the immediate connection between the sentient principle and the body may be established by kinds of ethereal matter, which can never be evident to the senses, and which may bear the same relations to heat, light, and electricity that these refined forms or modes of existence of matter bear to the gases. Motion is most easily produced by the lighter species of matter; and yet imponderable agents, such as electricity, possess force sufficient to overturn the weightiest structures. Nothing can be farther from my meaning than to attempt any definition on this subject, nor would I ever embrace or give authority to that idea of Newton, who supposes that the immediate cause of sensation may be in undulations of an ethereal medium. It does not, however, appear improbable to me that some of the more refined machinery of thought may adhere, even in another state, to the sentient principle; for, though the organs of gross sensation--the nerves and brain--are destroyed by death, yet something of the more ethereal nature, which I have supposed, may be less destructible. And I sometimes imagine that many of those powers, which have been called instinctive, belong to the more refined clothing of the spirit; conscience, indeed, seems to have some undefined source, and may bear relation to a former state of being.

_Eub_.--All your notions are merely ingenious speculations. Revelation gives no authority to your ideas of spiritual nature; the Christian immortality is founded upon the resurrection of the body.

_The Unknown_.--This I will not allow. Even in the Mosaic history of the creation of man his frame is made in the image of G.o.d--that is, capable of intelligence; and the Creator breathes into it the breath of life, His own essence. Then our Saviour has said, "of the G.o.d of Abraham, of Isaac, and of Jacob." "He is not the G.o.d of the dead, but of the living." St. Paul has described the clothing of the spirit in a new and glorious body, taking the a.n.a.logy from the living germ in the seed of the plant, which is not quickened till after apparent death; and the catastrophe of our planet, which, it is revealed, is to be destroyed and purified by fire before it is fitted for the habitation of the blest, is in perfect harmony with the view I have ventured to suggest.

_Eub_.--I cannot make your notions coincide with what I have been accustomed to consider the meaning of Holy Writ. You allow everything belonging to the material life to be dependent upon the organisation of the body, and yet you imagine the spirit after death clothed with a new body; and, in the system of rewards and punishments, this body is rendered happy or miserable for actions committed by another and extinct frame. A particular organisation may impel to improper and immoral gratification; it does not appear to me, according to the principles of eternal justice, that the body of the resurrection should be punished for crimes dependent upon a conformation now dissolved and destroyed.

_The Unknown_.--Nothing is more absurd, I may say more impious, than for man, with a ken surrounded by the dense mists of sense, to reason respecting the decrees of eternal justice. You adopt here the same limited view that you embraced in reasoning against the indestructibility of the sentient principle in man from the apparent division of the living principle in the polypus, not recollecting that to prove a quality can be increased or exalted does not prove that it can be annihilated. If there be, which I think cannot be doubted, a consciousness of good and evil constantly belonging to the sentient principle in man, then rewards and punishments naturally belong to acts of this consciousness, to obedience, or disobedience; and the indestructibility of the sentient being is necessary to the decrees of eternal justice. On your view, even in this life, just punishments for crimes would be almost impossible; for the materials of which human beings are composed change rapidly, and in a few years probably not an atom of the primitive structure remains yet even the materialist is obliged in old age to do penance for the sins of his youth, and does not complain of the injustice of his decrepit body, entirely changed and made stiff by time, suffering for the intemperance of his youthful flexible frame. On my idea, conscience is the frame of the mind, fitted for its probation in mortality. And this is in exact accordance with the foundations of our religion, the Divine origin of which is marked no less by its history than its harmony with the principles of our nature. Obedience to its precepts not only prepares for a better state of existence in another world, but is likewise calculated to make us happy here. We are constantly taught to renounce sensual pleasure and selfish gratifications, to forget our body and sensible organs, to a.s.sociate our pleasures with mind, to fix our affections upon the great ideal generalisation of intelligence in the one Supreme Being. And that we are capable of forming to ourselves an imperfect idea even of the infinite mind is, I think, a strong presumption of our own immortality, and of the distinct relation which our finite knowledge bears to eternal wisdom.

_Phil_.--I am pleased with your views; they coincide with those I had formed at the time my imagination was employed upon the vision of the Colosaeum, which I repeated to you, and are not in opposition with the opinions that the cool judgment and sound and humble faith of Ambrosio have led me since to embrace. The doctrine of the materialists was always, even in my youth, a cold, heavy, dull, and insupportable doctrine to me, and necessarily tending to Atheism. When I had heard, with disgust, in the dissecting-rooms the plan of the physiologist of the gradual accretion of matter, and its becoming endowed with irritability, ripening into sensibility and acquiring such organs as were necessary, by its own inherent forces, and at last rising into intellectual existence, a walk into the green fields or woods by the banks of rivers brought back my feelings from nature to G.o.d; I saw in all the powers of matter the instruments of the Deity; the sunbeams, the breath of the zephyr, awakened animation in forms prepared by Divine intelligence to receive it; the insensate seed, the slumbering egg, which were to be vivified, appeared like the new-born animal, works of a Divine mind; I saw love as the creative principle in the material world, and this love only as a Divine attribute. Then, my own mind, I felt connected with new sensations and indefinite hopes, a thirst for immortality; the great names of other ages and of distant nations appeared to me to be still living around me; and, even in the funeral monuments of the heroic and the great, I saw, as it were, the decree of the indestructibility of mind. These feelings, though generally considered as poetical, yet, I think, offer a sound philosophical argument in favour of the immortality of the soul. In all the habits and instincts of young animals their feelings or movements may be traced in intimate relation to their improved perfect state; their sports have always affinities to their modes of hunting or catching their food, and young birds, even in the nest, show marks of fondness which, when their frames are developed, become signs of actions necessary to the reproduction and preservation of the species. The desire of glory, of honour, of immortal fame, and of constant knowledge, so usual in young persons of well-const.i.tuted minds, cannot, I think, be other than symptoms of the infinite and progressive nature of intellect--hopes which, as they cannot be gratified here, belong to a frame of mind suited to a n.o.bler state of existence.

_The Unknown_.--Religion, whether natural or revealed, has always the same beneficial influence on the mind. In youth, in health, and prosperity, it awakens feelings of grat.i.tude and sublime love, and purifies at the same time that it exalts; but it is in misfortune, in sickness, in age, that its effects are most truly and beneficially felt; when submission in faith and humble trust in the Divine will, from duties become pleasures, undecaying sources of consolation; then it creates powers which were believed to be extinct, and gives a freshness to the mind which was supposed to have pa.s.sed away for ever, but which is now renovated as an immortal hope; then it is the Pharos, guiding the wave- tost mariner to his home, as the calm and beautiful still basins or fiords, surrounded by tranquil groves and pastoral meadows, to the Norwegian pilot escaping from a heavy storm in the north sea, or as the green and dewy spot gus.h.i.+ng with fountains to the exhausted and thirsty traveller in the midst of the desert. Its influence outlives all earthly enjoyments, and becomes stronger as the organs decay and the frame dissolves; it appears as that evening star of light in the horizon of life, which, we are sure, is to become in another season a morning star, and it throws its radiance through the gloom and shadow of death.

DIALOGUE THE FIFTH. THE CHEMICAL PHILOSOPHER.

I had been made religious by the conversations of Ambrosio in Italy; my faith was strengthened and exalted by the opinions of the Unknown, for whom I had not merely that veneration awakened by exalted talents, but a strong affection founded upon the essential benefit of the preservation of my life owing to him. I ventured, the evening after our visit to the cave of Adelsberg, to ask him some questions relating to his history and adventures. He said, "To attempt to give you any idea of the formation of my character would lead me into the history of my youth, which almost approaches to a tale of romance. The source of the little information and intelligence I possess I must refer to a restless activity of spirit, a love of glory which ever belonged to my infancy, and a sensibility easily excited and not easily conquered. My parentage was humble, yet I can believe a traditional history of my paternal grandmother, that the origin of our family was from an old Norman stock; I found this belief upon certain feelings which I can only refer to an hereditary source, a pride of decorum, a tact and refinement even in boyhood, and which are contradictory to the idea of an origin from a race of peasants. Accident opened to me in early youth a philosophical career, which I pursued with success. In manhood fortune smiled upon me and made me independent; I then really became a philosopher, and pursued my travels with the object of instructing myself and of benefiting mankind. I have seen most parts of Europe, and conversed, I believe, with all the ill.u.s.trious men of science belonging to them. My life has not been unlike that of the ancient Greek sages. I have added some little to the quant.i.ty of human knowledge, and I have endeavoured to add something to the quant.i.ty of human happiness. In my early life I was a sceptic; I have informed you how I became a believer, and I constantly bless the Supreme Intelligence for the favour of some gleams of Divine light which have been vouchsafed to me in this our state of darkness and doubt."

_Phil_.--I am surprised that with your powers you did not enter into a professional career either of law or politics; you would have gained the highest honours and distinctions.

_The Unknown_.--To me there never has been a higher source of honour or distinction than that connected with advances in science. I have not possessed enough of the eagle in my character to make a direct flight to the loftiest alt.i.tudes in the social world, and I certainly never endeavoured to reach those heights by using the creeping powers of the reptile who, in ascending, generally chooses the dirtiest path, because it is the easiest.

_Eub_.--I have often wondered that men of fortune and of rank do not apply themselves more to philosophical pursuits; they offer a delightful and enviable road to distinction, one founded upon the blessings and benefits conferred on our fellow-creatures; they do not supply the same sources of temporary popularity as successes in the senate or at the bar, but the glory resulting from them is permanent and independent of vulgar taste or caprice. In looking back to the history of the last five reigns in England, we find Boyles, Cavendishes, and Howards, who rendered those great names more ill.u.s.trious by their scientific honours; but we may in vain search the aristocracy now for philosophers, and there are very few persons who pursue science with true dignity; it is followed more as connected with objects of profit than those of fame, and there are fifty persons who take out patents for supposed inventions for one who makes a real discovery.

_Phil_.--The information we have already received from you proves to me that chemistry has been your favourite pursuit. I am surprised at this.

The higher-mathematics and pure physics appear to me to offer much more n.o.ble objects of contemplation and fields of discovery, and, practically considered, the results of the chemist are much more humble, belonging princ.i.p.ally to the apothecary's shop and the kitchen.

_Eub_.--I feel disposed to join you in attacking this favourite study of our friend, but merely to provoke him to defend it. I wish our attack would induce him to vindicate his science, and that we might enjoy a little of the sport of literary gladiators, at least, in order to call forth his skill and awaken his eloquence.

_The Unknown_.--I have no objection. Let there be a fair discussion; remember we fight only with foils, and the point of mine shall be covered with velvet. In your attack upon chemistry, Philalethes, you limited the use of it to the apothecary's shop and the kitchen. The first is an equivocal use; by introducing it into the kitchen you make it an art fundamental to all others. But if what you had stated had really meant to be serious, it would not have deserved a reply; as it is in mere playfulness, it shall not be thrown away. I want eloquence, however, to adorn my subject, yet it is sufficiently exciting even to awaken feeling.

Persons in general look at the magnificent fabric of civilized society as the result of the acc.u.mulated labour, ingenuity, and enterprise of man through a long course of ages, without attempting to define what has been owing to the different branches of human industry and science; and usually attribute to politicians, statesmen, and warriors a much greater share than really belongs to them in the work: what they have done is in reality little. The beginning of civilization is the discovery of some useful arts by which men acquire property, comforts, or luxuries. The necessity or desire of preserving them leads to laws and social inst.i.tutions. The discovery of peculiar arts gives superiority to particular nations; and the love of power induces them to employ this superiority to subjugate other nations, who learn their arts, and ultimately adopt their manners; so that in reality the origin, as well as the progress and improvement, of civil society is founded in mechanical and chemical inventions. No people have ever arrived at any degree of perfection in their inst.i.tutions who have not possessed in a high degree the useful and refined arts. The comparison of savage and civilized man, in fact, demonstrates the triumph of chemical and mechanical philosophy as the causes not only of the physical, but ultimately even of moral improvement. Look at the condition of man in the lowest state in which we are acquainted with him. Take the native of New Holland, advanced only a few steps above the animal creation, and that princ.i.p.ally by the use of fire; naked, defending himself against wild beasts or killing them for food only by weapons made of wood hardened in the fire, or pointed with stones or fish bones; living only in holes dug out of the earth, or in huts rudely constructed of a few branches of trees covered with gra.s.s; having no approach to the enjoyment of luxuries or even comforts; unable to provide for his most pressing wants; having a language scarcely articulate, relating only to the great objects of nature, or to his most pressing necessities or desires, and living solitary or in single families, unacquainted with religion, government, or laws, submitted to the mercy of nature or the elements. How different is man in his highest state of cultivation; every part of his body covered with the products of different chemical and mechanical arts made not only useful in protecting him from the inclemency of the seasons but combined in forms of beauty and variety; creating out of the dust of the earth from the clay under his feet instruments of use and ornament; extracting metals from the rude ore and giving to them a hundred different shapes for a thousand different purposes; selecting and improving the vegetable productions with which he covers the earth; not only subduing but taming and domesticating the wildest, the fleetest, and the strongest inhabitants of the wood, the mountain, and the air; making the winds carry him on every part of the immense ocean; and compelling the elements of air, water, and even fire as it were to labour for him; concentrating in small s.p.a.ce materials which act as the thunderbolt, and directing their energies so as to destroy at immense distances; blasting the rock, removing the mountain, carrying water from the valley to the hill; perpetuating thought in imperishable words, rendering immortal the exertion of genius, and presenting them as common property to all awakening minds, becoming as it were the true image of divine intelligence receiving and bestowing the breath of life in the influence of civilization.

_Eub_.--Really you are in the poetical, not the chemical chair, or rather on the tripod. We claim from you some accuracy of detail, some minute information, some proofs of what you a.s.sert. What you attribute to the chemical and mechanical arts, we might with the same propriety attribute to the fine arts, to letters, to political improvement, and to those inventions of which Minerva and Apollo and not Vulcan are the patrons.

_The Unknown_.--I will be more minute. You will allow that the rendering skins insoluble in water by combining with them the astringent principle of certain vegetables is a chemical invention, and that without leather, our shoes, our carriages, our equipages would be very ill made; you will permit me to say, that the bleaching and dying of wool and silk, cotton, and flax, are chemical processes, and that the conversion of them into different clothes is a mechanical invention; that the working of iron, copper, tin, and lead, and the other metals, and the combining them in different alloys by which almost all the instruments necessary for the turner, the joiner, the stone-mason, the s.h.i.+p-builder, and the smith are made, are chemical inventions; even the press, to the influence of which I am disposed to attribute as much as you can do, could not have existed in any state of perfection without a metallic alloy; the combining of alkali and sand, and certain clays and flints together to form gla.s.s and porcelain is a chemical process; the colours which the artist employs to frame resemblances of natural objects, or to create combinations more beautiful than ever existed in Nature, are derived from chemistry; in short, in every branch of the common and fine arts, in every department of human industry, the influence of this science is felt, and we may find in the fable of Prometheus taking the flame from heaven to animate his man of clay an emblem of the effects of fire in its application to chemical purposes in creating the activity and almost the life of civil society.

_Phil_.--It appears to me that you attribute to science what in many cases has been the result of accident. The processes of most of the useful arts, which you call chemical, have been invented and improved without any refined views, without any general system of knowledge.

Lucretius attributes to accident the discovery of the fusion of the metals; a person in touching a sh.e.l.l-fish observes that it emits a purple liquid as a dye, hence the Tyrian purple; clay is observed to harden in the fire, and hence the invention of bricks, which could hardly fail ultimately to lead to the discovery of porcelain; oven gla.s.s, the most perfect and beautiful of those manufactures you call chemical, is said to have been discovered by accident; Theophrastus states that some merchants who were cooking on lumps of soda or natron, near the mouth of the river Belus, observed that a hard and vitreous substance was formed where the fused natron ran into the sand.

_The Unknown_.--I will readily allow that accident has had much to do with the origin of the arts as with the progress of the sciences. But it has been by scientific processes and experiments that these accidental results have been rendered really applicable to the purposes of common life. Besides, it requires a certain degree of knowledge and scientific combination to understand and seize upon the facts which have originated in accident. It is certain that in all fires alkaline substances and sand are fused together, and clay hardened; yet for ages after this discovery of fire, gla.s.s and porcelain were unknown till some men of genius profited by scientific combination often observed but never applied. It suits the indolence of those minds which never attempt anything, and which probably if they did attempt anything would not succeed, to refer to accident that which belongs to genius. It is sometimes said by such persons, that the discovery of the law of gravitation was owing to accident: and a ridiculous story is told of the falling of an apple as the cause of this discovery. As well might the invention of fluxions or the architectural wonders of the dome of St.

Peter's, or the miracles of art the St. John of Raphael or the Apollo Belvidere, be supposed to be owing to accidental combinations. In the progress of an art, from its rudest to its more perfect state, the whole process depends upon experiments. Science is in fact nothing more than the refinement of common sense making use of facts already known to acquire new facts. Clays which are yellow are known to burn red; calcareous earth renders flint fusible--the persons who have improved earthenware made their selections accordingly. Iron was discovered at least one thousand years before it was rendered malleable; and from what Herodotus says of this discovery, there can be little doubt that it was developed by a scientific worker in metals. Vitruvius tells us that the ceruleum, a colour made of copper, which exists in perfection in all the old paintings of the Greeks and Romans and on the mummies of the Egyptians, was discovered by an Egyptian king; there is therefore every reason to believe that it was not the result of accidental combination, but of experiments made for producing or improving colours. Amongst the ancient philosophers, many discoveries are attributed to Democritus and Anaxagoras; and, connected with chemical arts, the narrative of the inventions of Archimedes alone, by Plutarch, would seem to show how great is the effect of science in creating power. In modern times, the refining of sugar, the preparation of nitre, the manufacturing of acids, salts, &c., are all results of pure chemistry. Take gunpowder as a specimen; no person but a man infinitely diversifying his processes and guided by a.n.a.logy could have made such a discovery. Look into the books of the alchemists, and some idea may be formed of the effects of experiments. It is true, these persons were guided by false views, yet they made most useful researches; and Lord Bacon has justly compared them to the husbandman who, searching for an imaginary treasure, fertilised the soil. They might likewise be compared to persons who, looking for gold, discover the fragments of beautiful statues, which separately are of no value, and which appear of little value to the persons who found them; but which, when selected and put together by artists and their defective parts supplied, are found to be wonderfully perfect and worthy of conservation. Look to the progress of the arts since they have been enlightened by a system of science, and observe with what rapidity they have advanced. Again, the steam-engine in its rudest form was the result of a chemical experiment; in its refined state it required the combinations of all the most recondite principles of chemistry and mechanics, and that excellent philosopher who has given this wonderful instrument of power to civil society was led to the great improvements he made by the discoveries of a kindred genius on the heat absorbed when water becomes steam, and of the heat evolved when steam becomes water.

Even the most superficial observer must allow in this case a triumph of science, for what a wonderful impulse has this invention given to the progress of the arts and manufactories in our country, how much has it diminished labour, how much has it increased the real strength of the country! Acting as it were with a thousand hands, it has multiplied our active population; and receiving its elements of activity from the bowels of the earth, it performs operations which formerly were painful, oppressive, and unhealthy to the labourers, with regularity and constancy, and gives security and precision to the efforts of the manufacturer. And the inventions connected with the steam-engine, at the same time that they have greatly diminished labour of body, have tended to increase power of mind and intellectual resources. Adam Smith well observes that manufacturers are always more ingenious than husbandmen; and manufacturers who use machinery will probably always be found more ingenious than handicraft manufacturers. You spoke of porcelain as a result of accident; the improvements invented in this country, as well as those made in Germany and France, have been entirely the result of chemical experiments; the Dresden and the Sevres manufactories have been the work of men of science, and it was by multiplying his chemical researches that Wedgewood was enabled to produce at so cheap a rate those beautiful imitations which while they surpa.s.s the ancient vases in solidity and perfection of material, equal them in elegance, variety, and tasteful arrangement of their forms. In another department, the use of the electrical conductor was a pure scientific combination, and the sublimity of the discovery of the American philosopher was only equalled by the happy application he immediately made of it. In our own times it would be easy to point out numerous instances in which great improvements and beneficial results connected with the comforts, the happiness, and even life of our fellow creatures have been the results of scientific combinations; but I cannot do this without const.i.tuting myself a judge of the works of philosophers who are still alive, whose researches are known, whose labours are respected, and who will receive from posterity praises that their contemporaries hardly dare to bestow upon them.

_Eub_.--We will allow that you have shown in many cases the utility of scientific investigation as connected with the progress of the useful arts. But, in general, both the principles of chemistry are followed, and series of experiments performed without any view to utility; and a great noise is made if a new metal or a new substance is discovered, or if some abstracted law is made known relating to the phenomena of nature; yet, amongst the variety of new substances, few have been applied to any trifling use even, and the greater number have had no application at all.

And with respect to the general views of the science, it would be difficult to show that any real good had resulted from the discovery or extension of them. It does not add much to the dignity of a pursuit that those persons who have followed it for profit have really been most useful, and that the mere artisan or chemical manufacturer has done more for society than the chemical philosopher. Besides, it has always appeared to me that it is in the nature of this science to encourage mediocrity and to attach importance to insignificant things; very slight chemical labours seem to give persons a claim to the t.i.tle of philosopher--to have dissolved a few grains of chalk in an acid, to have shown that a very useless stone contains certain known ingredients, or that the colouring matter of a flower is soluble in acid and not in alkali, is thought by some a foundation for chemical celebrity. I once began to attend a course of chemical lectures and to read the journals containing the ephemeral productions of this science; I was dissatisfied with the nature of the evidence which the professor adopted in his demonstrations, and disgusted with the series of observations and experiments which were brought forward one month to be overturned the next. In November there was a Zingeberic acid, which in January was shown to have no existence; one year there was a vegetable acid, which the next was shown to be the same as an acid known thirty years ago; to- day a man was celebrated for having discovered a new metal or a new alkali, and they flourished like the scenes in a new pantomime only to disappear. Then, the great object of the hundred triflers in the science appeared to be to destroy the reputation of the three or four great men whose labours were really useful, and had in them something of dignity.

And, there not being enough of trifling results or false experiments to fill up the pages of the monthly journals, the deficiency was supplied by some crude theories or speculations of unknown persons, or by some ill- judged censure or partial praise of the editor.

_The Unknown_.--I deny _in toto_ the accuracy of what you are advancing.

I have already shown that real philosophers, not labouring for profit, have done much by their own inventions for the useful arts; and, amongst the new substances discovered, many have had immediate and very important applications. The chlorine, or oxymuriatic gas of Scheele, was scarcely known before it was applied by Berthollet to bleaching; scarcely was muriatic acid gas discovered by Priestley, when Guyton de Morveau used it for destroying contagion. Consider the varied and diversified applications of platinum, which has owed its existence as a useful metal entirely to the labours of an ill.u.s.trious chemical philosopher; look at the beautiful yellow afforded by one of the new metals, chrome; consider the medical effects of iodine in some of the most painful and disgusting maladies belonging to human nature, and remember how short a time investigations have been made for applying the new substances. Besides, the mechanical or chemical manufacturer has rarely discovered anything; he has merely applied what the philosopher has made known, he has merely worked upon the materials furnished to him. We have no history of the manner in which iron was rendered malleable; but we know that platinum could only have been worked by a person of the most refined chemical resources, who made multiplied experiments upon it after the most ingenious and profound views. But, waiving all common utility, all vulgar applications, there is something in knowing and understanding the operation of Nature, some pleasure in contemplating the order and harmony of the arrangements belonging to the terrestrial system of things. There is no absolute utility in poetry, but it gives pleasure, refines and exalts the mind. Philosophic pursuits have likewise a n.o.ble and independent use of this kind, and there is a double reason offered for pursuing them, for whilst in their sublime speculations they reach to the heavens, in their application they belong to the earth; whilst they exalt the intellect, they provide food for our common wants, and likewise minister to the n.o.blest appet.i.tes and most exalted views belonging to our nature. The results of this science are not like the temples of the ancients, in which statues of the G.o.ds were placed, where incense was offered and sacrifices were performed, and which were presented to the adoration of the mult.i.tude founded upon superst.i.tious feelings; but they are rather like the palaces of the moderns, to be admired and used, and where the statues, which in the ancients raised feelings of adoration and awe, now produce only feelings of pleasure, and gratify a refined taste.

It is surely a pure delight to know how and by what processes this earth is clothed with verdure and life, how the clouds, mists, and rain are formed, what causes all the changes of this terrestrial system of things, and by what divine laws order is preserved amidst apparent confusion. It is a sublime occupation to investigate the cause of the tempest and the volcano, and to point out their use in the economy of things, to bring the lightning from the clouds and make it subservient to our experiments, to produce, as it were, a microcosm in the laboratory of art, and to measure and weigh those invisible atoms which, by their motions and changes according to laws impressed upon them by the Divine Intelligence, const.i.tute the universe of things. The true chemical philosopher sees good in all the diversified forms of the external world. Whilst he investigates the operations of infinite power guided by infinite wisdom, all low prejudices, all mean superst.i.tions, disappear from his mind. He sees man an atom amidst atoms fixed upon a point in s.p.a.ce, and yet modifying the laws that are around him by understanding them, and gaining, as it were, a kind of dominion over time and an empire in material s.p.a.ce, and exerting on a scale infinitely small a power seeming a sort of shadow or reflection of a creative energy, and which ent.i.tles him to the distinction of being made in the image of G.o.d and animated by a spark of the Divine Mind. Whilst chemical pursuits exalt the understanding, they do not depress the imagination or weaken genuine feeling; whilst they give the mind habits of accuracy by obliging it to attend to facts, they likewise extend its a.n.a.logies, and though conversant with the minute forms of things, they have for their ultimate end the great and magnificent objects of Nature. They regard the formation of a crystal, the structure of a pebble, the nature of a clay or earth; and they apply to the causes of the diversity of our mountain chains, the appearances of the winds, thunderstorms, meteors, the earthquake, the volcano, and all those phenomena which offer the most striking images to the poet and the painter. They keep alive that inextinguishable thirst after knowledge which is one of the greatest characteristics of our nature, for every discovery opens a new field for investigation of facts, shows us the imperfection of our theories. It has justly been said that the greater the circle of light, the greater the boundary of darkness by which it is surrounded. This strictly applies to chemical inquiries, and hence they are wonderfully suited to the progressive nature of the human intellect, which by its increasing efforts to acquire a higher kind of wisdom, and a state in which truth is fully and brightly revealed, seems, as it were, to demonstrate its birthright to immortality.

_Eub_.--I am glad that our opposition has led you to so complete a vindication of your favourite science. I want no further proof of its utility. I regret that I have not before made it a particular object of study.

_Phil_.--As our friend has so fully convinced us of the importance of chemistry, I hope he will descend to some particulars as to its real nature, its objects, its instruments. I would willingly have a definition of chemistry and some idea of the qualifications necessary to become a chemist, and of the apparatus essential for understanding what has been already done in the science, and for pursuing new inquiries.

_The Unknown_.--There is nothing more difficult than a good definition, for it is scarcely possible to express in a few words the abstracted view of an infinite variety of facts. Dr. Black has defined chemistry to be that science which treats of the changes produced in bodies by motions of their ultimate particles or atoms, but this definition is hypothetical, for the ultimate particles or atoms are mere creations of the imagination. I will give you a definition, which will have the merit of novelty and which is probably general in its application. Chemistry relates to those operations by which the intimate nature of bodies is changed, or by which they acquire new properties. This definition will not only apply to the effects of mixture, but to the phenomena of electricity, and, in short, to all the changes which do not merely depend upon the motion or division of ma.s.ses of matter. However difficult it may have been to have given you a definition of chemistry, it is still more difficult to give you a detail of all the qualities necessary for a chemical philosopher. I will not name as many as Athenaeus has named for a cook, who, he says, ought to be a mathematician, a theoretical musician, a natural philosopher, a natural historian, &c., though you had a disposition just now to make chemistry merely subservient to the uses of the kitchen. But I will seriously mention some of the studies fundamental to the higher departments of this science; a man may be a good practical chemist perhaps without possessing them, but he never can become a great chemical philosopher. The person who wishes to understand the higher departments of chemistry, or to pursue them in their most interesting relations to the economy of Nature, ought to be well-grounded in elementary mathematics; he will oftener have to refer to arithmetic than algebra, and to algebra than to geometry. But all these sciences lend their aid to chemistry; arithmetic, in determining the proportions of a.n.a.lytical results and the relative weights of the elements of bodies; algebra, in ascertaining the laws of the pressure of elastic fluids, the force of vapour as dependent upon temperature, and the effects of ma.s.ses and surfaces on the communication and radiation of heat; the applications of geometry are princ.i.p.ally limited to the determination of the crystalline forms of bodies, which const.i.tute the most important type of their nature, and often offer useful hints for a.n.a.lytical researches respecting their composition. The first principles of natural philosophy or general physics ought not to be entirely unknown to the chemist. As the most active agents are fluids, elastic fluids, heat, light, and electricity, he ought to have a general knowledge of mechanics, hydrodynamics, pneumatics, optics, and electricity. Latin and Greek among the dead and French among the modern languages are necessary, and, as the most important after French, German and Italian. In natural history and in literature what belongs to a liberal education, such as that of our universities, is all that is required; indeed, a young man who has performed the ordinary course of college studies which are supposed fitted for common life and for refined society, has all the preliminary knowledge necessary to commence the study of chemistry. The apparatus essential to the modern chemical philosopher is much less bulky and expensive than that used by the ancients. An air pump, an electrical machine, a voltaic battery (all of which may be upon a small scale), a blow-pipe apparatus, a bellows and forge, a mercurial and water-gas apparatus, cups and basins of platinum and gla.s.s, and the common reagents of chemistry, are what are required. All the implements absolutely necessary may be carried in a small trunk, and some of the best and most refined researches of modern chemists have been made by means of an apparatus which might with ease be contained in a small travelling carriage, and the expense of which is only a few pounds. The facility with which chemical inquiries are carried on, and the simplicity of the apparatus, offer additional reasons, to those I have already given, for the pursuit of this science. It is not injurious to the health; the modern chemist is not like the ancient one, who pa.s.sed the greater part of his time exposed to the heat and smoke of a furnace and the unwholesome vapours of acids and alkalies and other menstrua, of which, for a single experiment, he consumed several pounds. His processes may be carried on in the drawing-room, and some of them are no less beautiful in appearance than satisfactory in their results. It was said, by an author belonging to the last century, of alchemy, "that its beginning was deceit, its progress labour, and its end beggary." It may be said of modern chemistry, that its beginning is pleasure, its progress knowledge, and its objects truth and utility. I have spoken of the scientific attainments necessary for the chemical philosopher; I will say a few words of the intellectual qualities necessary for discovery or for the advancement of the science. Amongst them patience, industry, and ne