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marks something like the culmination of a mor- ology, except as a searcher for coal, metallic ores, bid relish for the exploits of applied physics. Su- limestone, or gold, is not the popular science it is pernaturalism is either entirely discredited, or often supposed to be. It is too difficult, comprereduced to a quite tangible realism, and subjected hensive, and expensive a pursuit, to be largely folto manipulation—as in animal magnetism and phre-lowed by any but the highest grade of amateurs. nology. From chairs of chemistry, lectures are The number of unscientific persons, accordingly, delivered on the nature of the soul; and the pupils who realize to themselves, so that they can propof such a class, in a celebrated university, may be erly be said to believe, that coal was once wood, instructed one day as to the properties of magnesia and ironstone once mud, and that there formerly or cream of tartar, and learn, on the next, that the lived on this earth such creatures as Pterodactyles burning kisses which passionate lovers exchange, or Icthyosaurs, is, in fact, very small. Unscienare accompanied by actual flames, which the duly tific religious people are still, to a great extent, gifted may perceive hovering round their meeting | ready to account for every fossil by Noah's deluge; lips! So strangely in our own day has the once invisible eagle, who dwelt near the sun, submitted to have his wings clipped, and taken his place among tame geese and barn-door fowls.

and reluctant to make any creature older than Adam. The irreligious, semi-scientific public, on the other hand, reads eagerly whatever seems to contradict the book of Genesis; but understands too little of what it reads, and finds what little it understands too far removed from its everyday cares, hopes, and fears, to trouble itself much with the speculations of paleontology.

fright.

The natural history sciences, in short, although now of far greater interest to philosophers than they ever were before, have been completely eclipsed in general estimation by the experimental sciences. Travellers' tales have long been at The oldest and grandest of the sciences fares no a discount. The most distant places of the globe better. Although astronomy has recently been are now so near, in time, that it is worth no one's discovering planets at the rate at which she fortrouble to palm a deliberate fiction upon us as to merly discovered comets, and by her one gift to the their condition-when a few weeks at furthest may known heavens, of Neptune, has cast far into the expose the fabrication. Every fortnight brings a shade all the younger branches of knowledge, yet mail from India and the New World; so that two the public heard with perfect indifference the really weeks on an average bound the longevity of the idle, but for it, trustworthy announcement, that most plausible imported lie. The public, needy Neptune had gone a missing, or rather had never as it was, waited with patience for exact informa- been found. Were it to be rumored, however, tion concerning the Californian gold; and its pa- that the electric light had proved, or would prove tience has been rewarded. It is still more willing on the large scale, a total failure, its extinction to suspend its merely speculative curiosity till the would be lamented as a public calamity; or had it mail shall arrive. We now hear little, according- been but hinted that the wires of the electric telly, of marine or transmarine monsters; and the egraph were found to be rapidly losing their power few that do present themselves are called to so to conduct electricity, and would soon refuse to strict an account by Professor Owen and his breth-conduct it at all, the whole island would have taken ren, that if so much as a scale, a bristle, or a claw are out of order, it goes hard with them; In speaking thus, we must be understood as and they are likely to be refused their certificates, excluding from our reference not only all those like doubtful bankrupts. All this is well, and but who study science as science, and all those who wholesome discipline for the world of science. But study it professionally as the basis of art, but likethe unscientific public has gone far beyond the wise all that large class of intelligent amateurs of most sceptical naturalist, in excluding from favor both sexes, who cannot be divided by a sharp line the once prized objects of natural history and phe- of demarcation from the students of science, or art, nomenal science. The only rare animals that have among whom they are often amply entitled to take recently excited interest have been all, we think, their places. But after deducting the philosopher, of the human species-Red Indians, Bosjesmans, the professional man, and the amateur, there reand Tom Thumb. Zoological gardens are every-mains the great bulk of the people of all ranks, where in Great Britain struggling against extinc- who only indirectly and occasionally interest themtion, and are indebted in many places to the selves in science. They are very important, howhumiliating assistance of fireworks or gymnastic ever, not only by their numerical proponderance, exhibitions for their prolonged existence. How and as the raw material out of which the special great the extremity is, may be gathered from the students must be drafted, but likewise as filling the fact, that even the Zoological Society of London important offices in the community of treasurer, has gone the unusual length of prosecuting the banker, and pursebearer-and as furnishing the defaulters among its members for their arrears. supplies, without which neither science nor art, in The same spirit appears in the loud outcry at pres- many of their provinces, any more than war, can ent raised against the expenditure of public money be carried on. on the palm-house at Kew-whilst thousands which The sciences which the public, thus defined, at no tax-gatherer demanded have been voluntarily present crowds to popular lectures to hear exflung away on hopeless projects which experimen- pounded, are Natural Philosophy and Chemistry tal physics were rashly supposed to sanction. Ge--though it would probably be more just to say

that the arts springing out of these sciences are popular, than that the sciences themselves are. The laws regulating the elasticity of steam at different temperatures, the theory of waves, the "Idea of Polarity," the doctrines of diamagnetism, of electromagnetics, of isomerism or organic types, and much else, find no favor with such disciples; but screw-propellers, electric lights, and new manures are cordially welcomed.

The preference thus shown for the sciences of Experiment, as contrasted with those of Observation, appears to admit of a twofold explanation. The former have always the charms of novelty about them; the latter have long been familiar to all. Among the sweetest remembrances, no doubt, of happy childhood, are the early listening at a mother's knee to the sacred record of the Creation; the appointment of the sun to rule the day, and the moon to rule the night; and Adam's giving names to the living creatures in the garden of Eden. Nor is there any toy more welcome to children than the well-freighted Dutch-built Noah's ark, nor any spectacle more delightful than a wild beast show, or a peep through a telescope at the man in the moon. But when childhood and youth are once gone by, natural history is but too often left behind with them; and the starry heavens are seldom consulted-except at the changes of the moon, when the roads are dark and the weather threatening.

localities of valuable fisheries, and of botany in introducing new vegetables, have been unobtrusively rendered; and have not come before the public in such a way as either to startle and be wondered at, or even to be understood or appreciated. Mechanics is applauded indeed for its steam-ships; but geology is not thanked for discovering, in Labuan, Chili, Australia, Vancouver's Island, and elsewhere, the coals, without which the ocean steamers could never have ventured on their stupendous careers. Chemistry has the whole credit of introducing guano; the fertil izing virtues of which had, however, been indicated by natural history long before chemistry had subjected it to analysis.

This habitual application of an utilitarian test to the sciences has necessarily excluded from attention some of the noblest of them. What was the planet Neptune to the utilitarian public, or that public to Neptune? His appearance in the heavens did not lead to any reduction in the window tax, or to any saving in candles. The skies looked no brighter for his coming, and the street lamps were as needful as before. The sea-serpent comes home to no man's business, and we trust will come home to no man's bosom. But the gunpowdermakers naturally enough quailed at the report of gun-cotton; and Sir Walter Scott's famous stagecoach companion, who, silent on every subject suggested for conversation, exclaimed at last, "Tak me on bend leather, and I'm your man!" would, if now alive, have taken interest in at least one additional topic, and have woke up at the sound of "gutta percha soles." The shareholders in the gas companies go about anxiously inquiring concerning the electric light; and coal merchants look blank at a recent newspaper paragraph which announces a method of producing an inflammable vapor from resin, charcoal, and water.

A character of peacefulness, serenity, and unchangeableness, belongs to the phenomenal sciences; and is one of their charms for those who study them profoundly and this indeed is more or less clearly perceived by all. The heavens upon which we gaze are felt to be the heavens to which the first pair lifted their eyes in Paradise. The plants and animals we now see are not distinguishable from those which the Egyptian draughtsman made his designs from, or the Greek In all this, however, there is nothing surprising, artist carved on his relievos. But this thought, and not much to be lamented. The scientific disso soothing in some moods of mind, is out of keep-coveries of recent years, and their marvellous appliing with the turbulent activity of busy manhood cations in the arts, have been of such a nature and -especially as it occupies itself. in our own coun- magnitude, as to astonish the most sober philosotry at present. Man's newest planet is probably phers; so that we cannot wonder that they have heaven's oldest one. The last discovered flower filled the less reflecting public with extravagant has been growing for any one to pluck, since the hopes and fears. We are far from wishing to flood; and kangaroos were in New Holland before impute to the mass of the people a merely selfish Britons were in Great Britain. An air of majes- or sordid interest in applied science. The least tic antiquity and completeness belongs almost avaricious may well take alarm, at the prospect of exclusively to the phenomenal sciences. But even a single unlucky invention ruining his trade or this makes them less attractive to a generation liv- profession; and in a densely peopled country like ing more in the future than the past. In addition this, enterprising young men, unpossessed of capitoo, to the great charm novelty, the idea of Power tal, naturally entertain sanguine expectations as to is much more connected by the people with the the substantial gains and honorable independence experimental than the phenomenal sciences. The which may accrue to them from one successful experimental sciences have in truth, within this investigation or ingenious device. But apart altocentury, effected so vast a revolution in the politi-gether from the perception of a pecuniary interest cal, commercial, and social relations of the world, in the progress of discovery, every newspaper that men do not now know what next to dread, or to expect, from them. The natural history and phenomenal sciences, on the other hand, have not very visibly affected the recent progress of mankind. The services of geology in discovering valuable minerals, of zoology in pointing out the

reader, however unscientific, perceives that the world is moving onwards at an accelerated ratewhich, according to his temperament, exceedingly delights or exceedingly alarms him. Intelligent appreciation, in short, childish fear, childish won der, a feverish spirit of speculation, and a strong

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infusion of cupidity, are all strangely mingled in but an electro-magnetic steam fire-balloon, which the popular estimate of what the sciences are des- will cleave the air like a thunderbolt, and ge tined to effect for the world. The general faith straight to its destination as the crow flies, is an in science as a wonder-worker is at present un- invention which many hope to see realized, before limited; and along with this there is cherished the railways are quite worn to pieces. We may soon conviction that every discovery and invention expect, too, it seems, to shoot our natural enemies admits of a practical application to the welfare of with saw-dust fired from guns of the long range men. Is a new vegetable product brought to this pointed at the proper angle, as settled by the country from abroad, or a new chemical compound astronomer-royal; which will enable the Wooldiscovered, or a novel physical phenomenon re-wich artillerymen (who will hereafter be recruited corded? The question is immediately asked, cui from the blind asylums) to bombard Canton, or bono? What is it good for? Is food or drink to be got out of it? wherever else the natural enemy is, and save the Will it make hats, or shoes, or necessity of sending troops to the colonies. A cover umbrellas ? Will it kill or heal? drive a steam-engine, or make a mill go? And tented, will fertilize a field; and the same amount Will it snuff-box full of the new manure, about to be patruly this cui bono question has of late been so often of the new explosive will dismantle the fortificasatisfactorily answered, that we cannot wonder tions of Paris. By means of the fish-tail propeller that the public should persist in putting it, some- to be shortly laid before the Admiralty, the Atlanwhat eagerly, to every discoverer and inventor, tic will be crossed in three days. and should believe that if a substance has one valuable application, it will prove, if further in-floating through the brain of many at the present Dreams little less extravagant than these are vestigated, to have a thousand. not been known in this country ten years; and here laid them down, for then their visionary charGutta percha has day; not so sharply defined, perhaps, as we have already it would be more difficult to say what pur-acter would be detected; but sufficiently distinct to poses it has not been applied to, than to enumerate fill the dreamers with a feverish anticipation of those to which it has been applied. Gun-cotton what the future is to effect. had scarcely proved in the saddest way its power therefore, to tell the public betimes, that it is a We think it well, to kill, before certain ingenious Americans showed little crazed at present on the subject of applied that it has a remarkable power of healing, and science, and must learn to moderate its expecta forms the best sticking plaster for wounds. geons have not employed ether and chloroform as ments, destruction of life, property, and capital, a Sur- tions; otherwise, after some additional disappointanææsthetics for three years; and already an ether reaction will assuredly come-which, alike for the steam-engine is at work in Lyons, and a chloro- sake of the scientific and unscientific sections of the form engine in London. Polarization of light, as public, we should greatly deplore. a branch of science, is the enigma of enigmas to unthinking faith of the people, and the instinctively the public. For, to the What it is, is a small matter; but sagacious empiricism of the unscientific and semiwhat work it can perform is a great one. It must scientific, we are substantially indebted for many of use. The singularly ingenious the most precious gifts of modern science. Wheatstone, accordingly, has already partly satis-gifts are, no doubt, the true children of science; fied the public by making polarized light act as a but, like the ostrich, she would have left them in time-keeper, and has supplied us with a sky- the sand. They have to a great extent been nursed polariscope; a substitute for a sun-dial, but greatly and developed into their energetic manhood by other superior to it in usefulness and accuracy. Of than parental hands. Without science we should other sciences we need scarcely speak. Chemistry not have had our lighthouses, railways, locomohas long come down from her atomic altitudes and tive engines, ocean steamers, or telegraphs; but it elective affinities, and now scours and dyes, brews, needed something more than science to secure their bakes, cooks, and compounds drugs and manures, speedy realization. with contented composure. Electricity leaves her thunderbolt in the sky, and like Mercury dismissed from Olympus, acts as letter-carrier and message-boy. Even the mysterious magnetismwhich once seemed like a living principle to quiver in the compass-needle, is unclothed of mystery, and set to drive turning lathes. The public perceives all this, and has unlimited faith in man's power to conquer nature. The credulity which formerly fed upon unicorns, phoenixes, mermaids, vam-ity, that railways must go as nearly as possible in pires, krakens, pestilential comets, fairies, ghosts, straight lines and on dead levels; but empiricism witches, spectres, charms, curses, universal reme- would not read the statute-and railroads now medies, pactions with Satan, and the like, now tam- ander safely in winding curves, and up and down pers with chemistry, electricity, and magnetism, most formidable slopes. It is the combination, in as it once did with the invisible world. swiftness, seven league boots, and Fortunatus' bold, sagacious, and often reckless empiricism, that Shoes of short, of rigid, cautious, hesitating science, with wishing caps, are banished even from the nursery; has made the Anglo-Saxon races in the old and

turn to some

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hand into her pocket, and become shareholder and Had not blind faith put her banker, science must have wanted the black-board and chalk of actual trial, with which alone the necessary problems could be solved. tating empiricism stopped its ears, when it was An unhesitold by the oracles of science that no steam-ship could possibly cross the Atlantic-and incontinently freighted goods for New York-which were duly delivered! It was laid down, with equal author

new world, excel all other modern people as con- | to be answered before the effects of electricity are querors of physical nature.

We select one of their recent achievements, in which, however, other races than the Anglo-Saxon have a large share, for present notice-namely, the Electric Telegraph.

considered. Of the nature of heat and of light, as well as of magnetism, we are in truth still quite ignorant; but we do not hesitate to discuss the changes which matter undergoes when illuminated, heated, or magnetized, without waiting till our theories of heat, light, and magnetism are perfect. We can do the same, therefore, with electricity, in explaining the telegraph, or any other electrical contrivance-provided we adopt some provisional theory as to its nature, which shall supply us with suitable terms for describing the phenomena, although it may be quite inadequate to account for them.

Two views, setting aside minor modifications, are entertained concerning the nature of electricity —very analogous to those now held concerning the nature of heat, light, and magnetism. According to the one view, electricity is a state, condition, or power of matter. According to the other view, electricity is a peculiar substance, or form or kind of matter. The latter is the more easily apprehended hypothesis; and supplies the nomenclature almost universally adopted in describing electrical

probable, the opposite belief. Electricity, then, may be assumed to be a highly attenuated substance-analogous to an elastic fluid, such as hydrogen gas, but infinitely lighter; in truth, not sensibly heavy at all. In bodies not exhibiting electrical phenomena this imponderable entity is supposed to exist in a latent or insensible condition,

In what follows we shall not attempt a minute description of the entire machinery of the telegraph, but confine ourselves to an explanation of what is essential to it as an electrical contrivance. A full description of it has not yet appeared in our language. A treatise, however, is announced as in the press, "On Electricity; its Theory, and practical Application," from the pen of M. de la Rive, the eminent philosopher of Geneva; and a special work on the telegraph is understood to be in preparation by one of our own electricians. Meanwhile, an excellent description of the general principles of the telegraph, and the mode in which these have been carried out in practice, will be found in Mr. Charles Knight's "Companion to the British Almanac for 1813 and 1848," and in the Révue des deux Mondes of August last. We are indebted, however, to a French author for the only systematic treatise we possess, as yet, on the sub-phenomena, even by those who prefer, as more ject. The Abbé Moigno's work on Electric Telegraphy has much of the well-ordered method and admirable perspicuity which characterize the scientific writings of his countrymen; and he displays, in the execution of his task, more than their ordinary vivacity in discussing questions of physics. His work is, in consequence, as lively and entertaining as it is instructive; and is peculiarly valu-hidden as it were in their substance or pores. able for its ample discussion of the relative merits of the different eminent men who have contributed to the perfection of the telegraph. This discussion carries the author over delicate ground (which we shall altogether avoid); for the majority of the inventors and improvers of the electric telegraph are still living, and claims of priority have been keenly contested among them. We must do the abbé the justice to say that, in disposing of these claims, he has shown a praiseworthy impartiality, and, in particular, a liberality towards the English electricians, especially Wheatstone, such as we do not find every day in French historical or polemical works. He is a little hard, in the body of his treatise, upon Professor Morse, of America, whom he accuses of claiming too much; adding, by way of justification alike of the professor and of his own judgment upon him, that "Frère Jonathan est très exalté, de sa nature." But he frankly acknowledges, in a postscript, that he has been "trop sévère envers M. Morse ;" and for this, and certain other hasty but not deliberately ungenerous judgments, cheerfully apologizes on the plea of "ma vivacité." A translation of M. Moigno's volume would form an admirable basis for an English standard work on the Electric Telegraph.

A difficulty, at first sight very formidable, attends all explanations of electrical phenomena. The question is asked, What is electricity? And to this no categorical answer can yet be returned. The question, however, may be set aside, as not requiring

Bodies, on the other hand, which manifest electrical phenomena, have the imponderable fluid set free at their surfaces, in an active, sensible, or nonlatent condition; so that it envelops them, as a fog does a mountain-top; or flows over them, as smoke does over the mast of a ship; or flows through them, as a current of warm water streams through a mass of cold. Electricity, as thus defined, is as invisible as common air; but when its intensity is high, it is cognizable by all the senses. It addresses the eye by its spark or-lightning-flash; the ear by its snap or thunder; the nostrils by a peculiar indescribable odor which it develops; the tongue by an equally peculiar taste which it occasions; and the organs of touch by its characteristic shock. The unknown something, condition, or kind of matter, which is the cause of those and many other phenomena, is electricity. We shall, for the present, write of it as a kind of matter, i. e., as something over and above or superadded to the body, whatever that be, which exhibits electrical phenomena; so that a telegraph-wire will be referred to, as conveying a current of substantial electricity, as a gas-pipe conveys gas, or a waterpipe water. Before, however, we can consider how this wonderful agent is made to convey intelligence, we require to notice certain relations of electricity which must be discussed before the explanation can proceed.

The phraseology of scientific treatises, in reference to electrical phenomena, is very apt to mislead

and perplex those who consult them for informa- | time. The intensity of electricity is less easily tion concerning special points. Such terms con- measured; but is well enough indicated by the tinually occur as, statical electricity, dynamical ease with which it can travel through bad conelectricity, positive electricity, negative electricity, ductors; by its power to overcome energetic electricity of tension, electricity of quantity, fric- chemical affinity, such as that which binds totion electricity, voltaic electricity, animal elec-gether the elements of water; by the length of tricity, magneto-electricity, thermo-electricity-till space across which it can pass through dry air the distracted reader, who finds one electricity perplexing enough, loses count and heart, and closes the treatise in despair. But this formidable list of electricities, which might readily have been lengthened, fortunately admits of being reduced to two kinds of electricity, and two modifications of each kind. The kinds are Positive and Negative electricity. The modifications are electricity of Tension, and electricity of Quantity. Statical and dynamical refer respectively to free electricity, as either at rest or in motion; and the five other titles merely point to certain important sources of electricity-which, however, is essentially the same, whatever be its source. The titles, positive and negative, apply to a much deeper and more fundamental peculiarity of electricity than the terms tension and quantity; but the latter are more important in reference to its practical applications; inasmuch as they are variable; whilst the twofold positive and negative relation of this agent is constant-and, so far as we at present know, inseparable from the very existence and manifestation of all electricity. We shall discuss this duplex character of electrical force presently; but it will be better appreciated a large animal; and it can force its way along after the difference between electricity of tension and electricity of quantity has been shortly explained.

(as in the case of the lightning flash striking a tree from a great distance); by the attractions and repulsions it produces in light bodies; and by the severity of the shock it occasions to living animals. Tried by those tests, and by others, we find that the electricity of the friction-machine, of an insulated steam-boiler, or of a thundercloud, has extraordinary intensity-while its quantity is excessively small. We speak very much within bounds when we state, that the whole electricity of a destructive thunder-storm would not suffice for the electro-gilding of a single pin-so insignificant is its amount. A small copper wire, dipped into an acid along with a wire. of zinc, would evolve more electricity in a few seconds than the largest friction electrical machine, kept constantly revolving, would furnish in many weeks. No shock, on the other hand, would be occasioned by the electricity from the immersed wires; nor would it produce a spark, or decompose water-so low is its intensity. A double-cell voltaic battery, again, produces electricity of such intensity that its shock would kill

very bad conductors-at the same time its quantity is so enormous that torrents of oxygen and hydrogen rise from the water it is made to decompose.

The phrases in question, which, philologically considered, are inaccurate and inelegant enough, Out of the distinctions thus explained have are used to denote the difference which is found arisen the phrases, electricity of Tension and electo exist between the quantity of electricity which tricity of Quantity. Interpreted literally, those any source of it, such as a voltaic battery, fur- terms have no meaning. We cannot recognize nishes, and the intensity of the electricity so fur- the existence of any Electricity, unless it possess nished. The distinction is one of the same kind such intensity as to produce some effect cognizable as that which is familiarly recognized in the by our senses; neither can any intensity be concase of light and heat. In the phosphorescence ceived as separated from a quantity of electricity of the sea, for example, which often spreads con- which possesses that intensity. The terms in use tinuously over thousands of miles, we have an illus- are thus very awkward. In ordinary language tration of light very feeble in intensity, but enor- we should use intense electricity for the one, and mous in quantity; a white-hot platinum wire, on leave the other undefined, or only call it abundant the other hand, gives out a very small quantity electricity. But those questionable terms are of light, but that of high intensity; while the sun now universally employed; and are rendered necradiates light at a maximum, as regards both in-essary by the circumstance already adverted to, tensity and quantity. A similar variation exists in the case of electricity; only that we have no electrical sun, i. e. no source, natural or artificial, of electricity alike great in quantity and in intensity.

We measure the quantity of electricity in many ways; but most conveniently by the amount of any chemical compound which it can decompose. A machine or battery, for example, which, when arranged so as to decompose water, evolves from it four cubic inches of oxygen and hydrogen in one minute, is furnishing twice the quantity of electricity supplied by an apparatus which evolves only two cubic inches of the gases in the same

that we have no artificial method of producing enormous quantities of electricity at a high intensity. As produced by us, therefore, it must always take a character from the preponderance of its intensity, or the preponderance of its quantity. Tension is merely a synonyme for intensity, which originated in the hypothesis of electricity being an elastic fluid, which might be regarded as existing in a thunder-cloud, or on the conductor of a friction-machine in a state of condensation or compression, like high-pressure steam struggling to escape from a boiler, or air seeking to force its way out of the chamber of an air-gun. The word tension, we believe, has been preferred

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