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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 in and reluctant to make any creature older than visible eagle, who dwelt near the sun, submitted to Adam. The irreligious, semi-scientific public, have his wings clipped, and taken his place among on the other hand, reads eagerly whatever seems tame geese and barn-door fowls.

to contradict the book of Genesis ; but underThe natural history sciences, in short, although stands too little of what it reads, and finds what now of far greater interest to philosophers than little it understands too far removed from its everythey ever were before, have been completely day cares, hopes, and fears, to trouble itself much eclipsed in general estimation by the experimen- with the speculations of palæontology. tal 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 fright. 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-1-though it would probably be more just to say that the arts springing out of these sciences are localities of valuable fisheries, and of botany in popular, than that the sciences themselves are. introducing new vegetables, have been unobtruThe laws regulating the elasticity of steam at dif- sively rendered ; and have not come before the ferent temperatures, the theory of waves, the public in such a way as either to startle and be “ Idea of Polarity,” the doctrines of diamagnetism, wondered at, or even to be understood or appreof electromagnetics, of isomerism or organic types, ciated. Mechanics is applauded indeed for its and much else, find no favor with such disciples ; steam-ships; but geology is not thanked for but screw-propellers, electric lights, and new ma- discovering, in Labuan, Chili, Australia, Vancounures are cordially welcomed.

ver's Island, and elsewhere, the coals, without The preference thus shown for the sciences of which the ocean steamers could never have venExperiment, as contrasted with those of Observa- tured on their stupendous careers. Chemistry has tion, appears to admit of a twofold explanation. the whole credit of introducing guano ; the fertil The former have always the charms of novelty izing virtues of which had, however, been indicated about them ; the latter have long been familiar to by natural history long before chemistry had suball. Among the sweetest remembrances, no doubt, jected it to analysis. of happy childhood, are the early listening at a This habitual application of an utilitarian test mother's knee to the sacred record of the Creation ; to the sciences has necessarily excluded from atthe appointment of the sun to rule the day, and the tention some of the noblest of them.

What was moon to rule the night; and Adam's giving names the planet Neptune to the utilitarian public, or that to the living creatures in the garden of Eden. public to Neptune ? His appearance in the heavNor is there any toy more welcome to children ens did not lead to any reduction in the window than the well-freighted Dutch-built Noah's ark, tax, or to any saving in candles. The skies looked nor any spectacle more delightful than a wild beast no brighter for his coming, and the street lamps show, or a peep through a telescope at the man were as needful as before. The sea-serpent comes in the moon. But when childhood and youth are home to no man's business, and we trust will come once gone by, natural history is but too often left home to no man's bosom. But the gunpowderbehind with them; and the starry heavens are sel- makers naturally enough quailed at the report of dom consulted-except at the changes of the moon, gun-cotton ; and Sir Walter Scott's famous stagewhen the roads are dark and the weather threat- coach companion, who, silent on every subject ening.

suggested for conversation, exclaimed at last, A character of peacefulness, serenity, and un- “ Tak me on bend leather, and I'm your man!" changeableness, belongs to the phenomenal sci- would, if now alive, have taken interest in at least ences; and is one of their charms for those who one additional topic, and have woke up at the study them profoundly: and this indeed is more sound of “gutta percha soles.” The shareholders or less clearly perceived by all. The heavens in the gas companies go about anxiously inquiring upon which we gaze are felt to be the heavens to concerning the electric light; and coal merchants which the first pair lifted their eyes in Paradise. look blank at a recent newspaper paragraph which The plants and animals we now see are not dis- announces a method of producing an inflammable tinguishable from those which the Egyptian vapor from resin, charcoal, and water. 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 food ; 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 inore 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 reader, however unscientific, perceives that the to expect, from them.

The natural history and world is moving onwards at an accelerated ratephenomenal sciences, on the other hand, have not which, according to his temperament, exceedingly very visibly affected the recent progress of man- delights or exceedingly alarms him. Intelligent kind. The services of geology in discovering appreciation, in short, childish fear, childish won valuable minerals, of zoology in pointing out the 'der, a feverish spirit of speculation, and a strong 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 fiies, 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 Wool. discovereel, 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 wherever else the natural enemy is, and save the be got out of it? Will it make hats, or shoes, or necessity of sending troops to the colonies. A cover umbrellas? Will it kill or heal? Will it snuff-box full of the new manure, about to be padrive a sieam-engine, or make a mill go? And tented, will fertilize a field; and the same amount truly 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 Admiraliy, the Atlan what eagerly, to every discoverer and inventor, tie will be crossed in three days. and should believe that if a substance has one Dreams little less extravagant than these are valuable application, it will prove, is further in- floating through the brain of many at the present vestigated, to have a thousand. Gutta percha has day ; not so sharply defined, perhaps, as we have not been known in this country ten years; and here laid them down, for then their visionary charalready 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. We think it well, had scarcely proved in the saddest way its power therefore, to tell the public betimes, that it is a 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 expeciaforms the best sticking plaster for wounds. Sur- tions; otherwise, after some additional disappointgeons have not employed ether and chloroform as ments, destruction of life, property, and capital, a anæsthetics for three years; and already an ether reäction 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. For, to the a branch of science, is the enigma of enigmas to unthinking faith of the people, and the instinctively the public. 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

The singularly ingenious the most precious gifts of modern science. These 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, locomo has 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. Had not blind faith put ber with contented composure. Electricity leaves hand into her pocket, and become shareholder and her thunderbolt in the sky, and like Mercury dis- banker, science must have wanted the black-board missed from Olympus, acts as letter-carrier and and chalk of actual trial, with which alone the message-boy. Even the mysterious magnetism— necessary problems could be solved. An unhesiwhich once seemed like a living principle to quiver tating empiricism stopped its ears, when it was in the compass-needle, is unclothed of mystery, and told by the oracles of science that no steam-ship set to drive turning lathes. The public perceives could possibly cross the Atlantic-and incontinently all this, and has unlimited faith in man's power freighted goods for New York—which were duly to conquer nature. The credulity which formerly delivered! It was laid down, with equal authorfed upon unicorns, phænixes, 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. Shoes of short, of rigid, cautious, hesitating science, with swiftness, seven league boots, and Fortunatus' bold, sagacious, and often reckless empiricism, that wishing caps, are banished even from the nursery ; has made the Anglo-Saxon races in the old and

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

considered. Of the nature of heat and of light, as We select one of their recent achievements, in well as of magnetism, we are in truth still quite which, however, other races than the Anglo-Saxon ignorant ; but we do not hesitate to discuss the have a large share, for present notice-namely, the changes which matter undergoes when illuminated, Electric Telegraph.

heated, or magnetized, without waiting till our In what follows we shall not attempt a minute theories of heat, light, and magnetism are perfect. description of the entire machinery of the tele- We can do the same, therefore, with electricity, in graph, but confine ourselves to an explanation of explaining the telegraph, or any other electrical what is essential to it as an electrical contrivance. contrivance-provided we adopt some provisional A full description of it has not yet appeared in our theory as to its nature, which shall supply us with language. A treatise, however, is announced as suitable terms for describing the phenomena, al

“ On Electricity ; its Theory, and though it may be quite inadequate to account for practical Application," from the pen of M. de la them. Rive, the eminent philosopher of Geneva ; and a Two views, setting aside minor modifications, special work on the telegraph is understood to be are entertained concerning the nature of electricity

in preparation by one of our own electricians. —very analogous to those now held concerning the .Meanwhile, an excellent description of the general nature of heat, light, and magnetism. According principles of the telegraph, and the mode in which to the one view, electricity is a state, condition, or these have been carried out in practice, will be power of matter. According to the other view, found in Mr. Charles Knight's “ Companion to the electricity is a peculiar substance, or form or kind British Almanac for 1813 and 1818,” and in the of matter. The latter is the more easily appreRérue des deux Mondes of August last. We are hended hypothesis ; and supplies the nomenclature indebted, however, to a French author for the only almost universally adopted in describing electrical 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 Tele- probable, the opposite belief. Electricity, then, graphy has much of the well-ordered method and may be assumed to be a highly attenuated subadmirable perspicuity which characterize the scien- stance—analogous to an elastic fluid, such as hytific writings of his countrymen ; and he displays, drogen gas, but infinitely lighter; in truth, not in the execution of his task, more than their ordi- sensibly heavy at all. In bodies not exhibiting nary vivacity in discussing questions of physics. electrical phenomena this imponderable entity is His work is, in consequence, as lively and enter- supposed to exist in a latent or insensible condition, taining 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 Bodies, on the other hand, which manifest elecof the different eminent men who have contributed trical phenomena, have the imponderable fluid set to the perfection of the telegraph. This discussion free at their surfaces, in an active, sensible, or noncarries the author over delicate ground (which we latent condition ; so that it envelops them, as a shall altogether avoid); for the majority of the fog does a mountain-top; or flows over them, as inventors and improvers of the electric telegraph smoke does over the mast of a ship; or flows are still living, and claims of priority have been through them, as a current of warm water streams keenly contested among them. We must do the through a mass of cold. Electricity, as thus deabbé the justice to say that, in disposing of these fined, is as invisible as common air ; but when its claims, he has shown a praiseworthy impartiality, intensity is high, it is cognizable by all the senses. and, in particular, a liberality towards the English It addresses the eye by its spark orolightning-flash; electricians, especially Wheatstone, such as we do the ear by its snap or thunder ; the nostrils by a not find every day in French historical or polemical peculiar indescribable odor which it develops ; the works. He is a little hard, in the body of his tongue by an equally peculiar taste which it occatreatise, upon Professor Morse, of America, whom sions; and the organs of touch by its characteristic he accuses of claiming too much ; adding, by way shock. The unknown something, condition, or of justification alike of the professor and of his own kind of matter, which is the cause of those and judgment upon him, that “ Frère Jonathan est très many other phenomena, is electricity. We shall, exalté, de sa nature." But he frankly acknowl- for the present, write of it as a kind of matter, i.e., edges, in a postscript, that he has been “trop sévère as something over and above or superadded to the envers M. Morse ;” and for this, and certain other body, whatever that be, which exhibits electrical hasty but not deliberately ungenerous judgments, phenomena ; so that a telegraph-wire will be cheerfully apologizes on the plea of“ ma vivacité.” referred to, as conveying a current of substantial A translation of M. Moigno’s volume would form electricity, as a gas-pipe conveys gas, or a wateran admirable basis for an English standard work pipe water. Before, however, we can consider on the Electric Telegraph.

how this wonderful agent is made to convey intelA difficulty, at first sight very formidable, attends ligence, we require to notice certain relations of all explanations of electrical phenomena. The ques- electricity which must be discussed before the extion is asked, What is electricity? And to this no planation can proceed. categorical answer can yet be returned. The ques- The phraseology of scientific treatises, in refertion, however, may be set aside, as not requiring ence to electrical phenomena, is very apt to mislead

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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 per- (as in the case of the lightning flash striking a plexing enough, loses count and heart, and closes tree from a great distance) ; by the attractions the treatise in despair. But this formidable list of and repulsions it produces in light bodies ; and by electricities, which might readily have been length- the severity of the shock it occasions to living ened, fortunately admits of being reduced to two kinds animals. Tried by those tests, and by others, of electricity, and two modifications of each kind. we find that the electricity of the friction-machine, The kinds are Positive and Negative electricity. The of an insulated steam-boiler, or of a thundermodifications are electricity of Tension, and elec- cloud, has extraordinary intensity-while its tricity of Quantity. Statical and dynamical refer quantity is excessively small.

We speak very respectively to free electricity, as either at rest or much within bounds when we state, that the in motion ; and the five other titles merely point to whole electricity of a destructive thunder-storm certain important sources of electricity—which, would not suffice for the electro-gilding of a sinhowever, is essentially the same, whatever be its gle pin-so insignificant is its amount. A small source. The titles, positive and negative, apply to copper wire, dipped into an acid along with a a much deeper and more fundamental peculiarity wire of zinc, would evolve more electricity in a of electricity than the terins tension and quantity ; few seconds than the largest friction electrical but the latter are more important in reference to machine, kept constantly revolving, would furnish its practical applications ; inasmuch as they are in many weeks. No shock, on the other hand, variable; whilst the twofold positive and negative would be occasioned by the electricity from the relation of this agent is constant—and, so far as immersed wires; nor would it produce a spark, we at present know, inseparable from the very ex- or decompose water-so low is its intensity. A istence and manifestation of all electricity. We double-cell voltaic battery, again, produces elecshall discuss this duplex character of electrical tricity of such intensity that its shock would kill 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 very bad conductors—at the same time its quanand electricity of quantity has been shortly ex- tity is so enormous that torrents of oxygen and plained.

hydrogen rise from the water it is made to decomThe phrases in question, which, philologically pose. 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 einployed ; 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 that we have no artificial method of producing in the case of electricity ; only that we have no enormous quantities of electricity at a high intenelectrical sun, i. e. no source, natural or artificial, sity. As produced by us, therefore, it must of electricity alike great in quantity and in inten- always take a character from the preponderance sity.

of its intensity, or the preponderance of its quanWe measure the quantity of electricity in many tity. Tension is merely a synonyme for intenways ; but most conveniently by the amount of sity, which originated in the hypothesis of elecany chemical compound which it can decompose. tricity being an elastic Auid, which might be A machine or battery, for example, which, when regarded as existing in a thunder-cloud, or on the arranged so as to decompose water, evolves from conductor of a friction-machine in a state of conit four cubic inches of oxygen and hydrogen in densation or compression, like high-pressure steam one minute, is furnishing twice the quantity of struggling to escape from a boiler, or air seeking electricity supplied by an apparatus which evolves to force its way out of the chamber of an air-gun. only two cubic inches of the gases in the same The word tension, we believe, has been preferred

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