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ther a light or heavy body fell fastest was ' nection of magnetism with electricity was a question on which no one then living yet to be hidden for sixty years; and the had any just opinion, and on which no inventions of the electric telegraph, the experiment had up to that time been locomotive engine, and the railway, were perhaps, ever made. The most prepos- to be witnessed by the grandchildren and terous opinions were entertained about great-grandchildren of these entering the path of projectiles in the air; no upon life. The earliest known of periodic microscope, telescope, barometer, or ther-comets had not then by its return verified mometer, had been heard of. The laws the sagacious prediction of Halley. The of simple refraction were unknown. Na- Herschel planet was yet to be added to tural philosophy existed only in the form the catalogue of our solar system: much of a rude and inaccurate mechanical as- more that mysterious star whose existence tronomy, a few useless optical and pneu- was foreshadowed and its discovery renmatical toys, and a great mass of dogmatic dered possible by the irregularities of the theories as to principles which ought (if motion of the former. The interminable they did not) to regulate the course of list of asteroids between Mars and Jupinature. Thus things were towards the ter had not then commenced. Our own middle of the sixteenth century.
globe had not yet been weighed as in a TWO HUNDRED YEARS SINCE, Newton was balance, and sun had not been seen to a boy at school. The mere ground plan of encircle sun in a mutual orbit connecting the solar system was pretty well understood, the law of gravity with those awful depths but gravitation was unthought of, or was, at of space. least, a mere surmise. With the exception This brief and partial enumeration of of Jupiter's satellites, the received number scientific discoveries may serve to give us of the heavenly bodies was then the same as a feeble insight into the general position the ancients bad acknowledged. The true of natural knowledge at periods not refigure of the earth was unrecognized. mote from our own in comparison with The Principia and the Optics of Newton the duration of our species, or even of were, of course, unwritten. The com- the historic period. When we attempt pound nature of light and its progressive to comprehend at a glance what have motion were unknown: only one law had been the general laws of progress during been added to optics since the time of these latter ages, we may find, notwithPtolemy. The air-pump had yet to be standing the extent and variety of the made; and the astonishing power of the subject, some recognizable features which hydraulic press was still a secret. Elec- distinguish their subdivisions. If we tricity and magnetism had hardly even a divide the centuries by their middle inname as sciences. Pure mathematics was stead of at their termination, we shall find still deficient in one great organ of modern these features more clearly brought out. research-the differential calculus. And though, as we have shown, the science
ONE CENTURY AGO, or in 1757, Watt of three hundred years back, or of 1550, had not dreamt of his steam-engine; the seems now to us one of almost infantile laws of heat were almost absolutely un- imbecility, and therefore a fit startingknown. The electricity obtained by rub- point of progress, we may as well include bing glass or sealing wax had begun to a period still a century more remote, have several of its properties investigated, which embraces almost the earliest efforts but comparatively little progress had then towards philosophical regeneration, and been made. The astonishing powers of also the memorable invention of printing, galvanism were as yet utterly unsuspected. which contributed incalculably to intellectChemistry was but a name, scarcely even ual progress of every kind. that. Water was regarded as a simple Thus our scheme of modern scientific substance, and the variety of the gases chronology embraces four centenary perwas unthought of. With the single ex- iods. The first, from 1450 to 1550, which ception of the achromatic telescope, the was characterized by the appearance of science of optics was where Newton left Leonardo da Vinci and Copernicus, may it in the previous century. The interfer- be termed Preludial or Anticipatory. It ence and polarization of light were un- was marked rather by the attempt to known terms. The partial recognition proceed in a right direction, and to attain of the latter property by Huyghens had a right method in learning the truths of been completely lost sight of. The con- nature, than by extensive or signal success
in this investigation. We might compare having thus triumphantly put forth her those efforts to the gleams of light which hidden strength. The truths of science gladden the view of the imprisoned Arctic are now no matters of speculation but of navigator when the sun promises once certainty, and being set in the open face more to revisit the melancholy realms of of day, are capable of being seen and adPolar frost. They tell as much of the mired by all men. thick darkness which is about to be dissi The fourth or modern age, extending pated as of the bright day of which they from 1750 to 1850, we would by no means are the herald. Or, to adapt the meta- qualify as a period of decline; yet neither phor to our own climate, the early strug- dare we assert that it is brighter or more gles of the human intellect to disperse admirable than that which preceded it. the obscurity and to awaken the death-like The glorious sun can not rise higher than unconcern of the middle ages, resemble it is at the Tropic, but in the sphere of inthose first bright days at the transition tellect it may pause there, and not hasten from winter to spring, when we welcome its going down. Still
, the character of the feeble sunbeam as a sure earnest of its the epoch may and must change. Time coming power.
and events never pause, but still leave The next age, (1550—1650,) which was their traces. The sky is perhaps less that of Kepler, Galileo, and"Bacon, may serene than before, the heat is more be emphatically called the age of Progress. scorching; the freshness of the springThe clear convictions then attained as to time and early summer is gone. The how science could best be promoted, and harvest is every where, the laborers by as to the errors which had hitherto ob- comparison few. Tender shoots have structed its career, and also the complete now become vigorous stems; the fair success which attended the application of flowers which decorated the orchards this, the inductive method, to great ques have become golden fruit which weighs tions of mechanics and astronomy, allow down the branches. The burden and us, without hyperbole, to compare it to heat of the day falls on the laborers of the advent of spring-cheering, warming, the fourth age. It is the season of Enand enlightening ; a time of emphatic largement and Application. Now we are transition from one condition of thinking to learn to use wisely and discreetly the and acting to another; a period of fulfill teachings of the past. Gross errors have ment; yet even more, a period of glorious been removed from our path. Other promise. The sun fairly mounted high entanglements arise-less palpable, less above the horizon, seems to triumph over positive, yet not always therefore easier darkness, “ shining more and more unto to overcome. Our time has also its lesthe perfect day." The forests are rapidly sons and its warnings. becoming clothed with foliage, the mea And now, to drop metaphor, let us look dows with verdure; a genial sap fills all more closely into what may be these lesorganic nature, and intense Life manifests sons and warnings. We may be sure itself at every pore.
that they have an application for all, The third centenary of our history While we are inquiring why some men (1650–1750,) or that of Newton, was failed formerly to know what they might emphatically the age of Attainment. Let have known, and why others now attain us think of ourselves as well as we please, knowledge without at the same time atlet us praise the enlightenment of the nine- taining wisdom, or the great end of knowteenth century, the diffusion of education, ledge,
we discover something which may the abatement of prejudices, and the be turned to account, not only by the few astonishing triumphs of art — no one who engage in the noble task of enlarging whose opinion is worth having, hopes or science and demonstrating new laws of expects that our age will eclipse that in nature, but by the many who are interwhich the Principia first appeared. It ested in learning what these laws are, and may be not inaptly likened to the early how they may best be employed for the weeks of glorious summer, when the benefit of humanity. mighty sun, approaching the solstice, shines It is a common mistake to pride ouron a world still fresh in all the beauty and selves upon our immunity from those erradiance of spring, whose verdure is un- rors or vices to which we are by circumsoiled, and whose fairest flowers are now stances or temperament least prone. In expanded. All nature seems to rejoice in like manner it is easy to dwell with com
placency on the ignorance and blunders pen, or fix the orbit of a planet by rule of the sixteenth century, and to thank and compass, was little likely to tease heaven that we are not as the men of himself by the interpretation of experithose days the spell-bound disciples of ments, or to disturb his rest by patiently Aristotle, the dogmatic priests of the In- watching the courses of the stars. The quisition, or devotees to perpetual motion caution of Galileo and the endurance of and the philosopher's stone. Unquestion- Kepler were, no doubt, bywords among ably we have little temptation to fall into the maintainers of the older views; but it these or similar mistakes; and if some is from their time that we date that atweaknesses are common to that age and tention to scrupulosity of observation our own, they are probably not those which is the very keystone of the inducagainst which we have most need to be tive philosophy. warned.
Henceforward it was no longer the preOf the erroneous modes of thought rogative of genius to attend only to great which enthralled the speculative minds of things, and to let the little things take the fifteenth and sixteenth centuries, two care of themselves. The theory of the were conspicuous : first, an overstrained universe turned, upon more than one ocand excessive regard to the opinions held casion, upon attention to what might be by the ancients; and secondly, an under- called minutiæ. Thus when the Ptoleestimate, and indeed a total misapprehen- maic theory (which accounted for the sion, of the value of experiment, and the apparent irregularities of the planetary manner of applying it so as to give useful motions by the hypothesis of Epicycles) results. Both of these defects may be was at length found to be unequal to retraced to a certain inactivity of mind presenting accurately the orbit of Mars, which rendered inquiry a tedious and re- the discrepancy was small considering the pulsive task. It was easier to adopt un- state of the astronomy of those days. It questioned the opinions of Aristotle than amounted to only eight minutes of a deto investigate their truth. It was easier gree. But great or small, no one could to insist that the beauty and simplicity of gainsay the error of the theory. Kepler, a circular curve fitted it alone for the with a spirit worthy of Newton, declared celestial motions, than to search out with that out of these 8' he would construct patience the actual form of the planetary a new astronomy: and he did so. The orbits. Nay, in the temper of those times, discovery of elliptic orbits, and that of the it was pleasanter and easier to demon- equable description of Areas (two of the strate upon paper that a body ten pounds corner-stones of the modern astronomical in weight must by the nature of things edifice) were the result. Some years fall ten times as far in a minute as a body later, Newton made a similar concession weighing one pound, than to ascend with to the unbending requirements of truth. Galileo the leaning tower of Pisa, and, In order to show that the fall of a stone allowing two weights to drop, to bear may be due to the very same force residtestimony to the result. Even the pa-ing in the earth, which, modified by the tience of the alchemist was a kind of vis proportion of the inverse square of the inertiæ. Experiments, indeed, they made distance, draws the moon from a rectilinear without number, but without the exercise course into an orbit approximately circular, of that vitality of thought which alone it was necessary to know the dimensions renders experiment fruitful. One thing of our earth in miles or feet. Newton, only they saw clearly, and that was the assuming the rude measure of a degree Result, which they desired to attain. The then in common use, making it equal to reasonable connection of the means and sixty English miles, obtained a result difthe end was overlooked. Experiment is fering about one eighth part from that an unavailing mockery if it is used only which his theory ought to have given. to support a foregone conclusion, The theory, though not forgotten, was
It was a real revolution, not only in abandoned for a time, and only after methods of inquiry, but in the temper eighteen or nineteen years' delay was it with which men approached the unknown resumed, when a more accurate measure questions of natural philosophy, which of our globe had come to his knowledge. characterized these ages of Revival and We almost tremble to think what might Progress. He who could create or de- have been the result had Newton died stroy a law of nature by a stroke of the during this long pause, and had the Prin
cipia consequently never been written. the region of abstractions whose applicaWe are almost tempted to say that the tions remain dubious, or into the still more genius of the new philosophy was too ex- debatable land conterminous between me acting, that the caution of her votaries taphysics and physics. had run to an excess in a direction oppos As regards the former or mechanical ite to the mistakes of the schoolmen. side of modern science, it must be owned
But it is not so. The uncompromising that the public generally are but indifferlesson of cautious induction which New- ent judges as to the inventions or the men ton thus practically taught, was better most worthy of applause and imitation. worth knowing than even the law of We do not mean that the calm verdict of gravity. The result has been that this an after generation is thus usually in error, lesson, now nearly two hundred years old, but rather that of lookers-on whilst social has never been forgotten. It will con- improvements based on scientific discortinue to be quoted for the instruction of eries are in progress. The great invenstudents for ages yet to come, in proof of tions of James Watt and of George the rigor which belongs to the right inter- Stephenson were only accepted after inpretation of nature.
numerable prejudices were overcome. It
is rather a matter of surprise than otherAnd now, turning from the earlier to wise that those distinguished and modest the latest age of modern science, from the engineers ever reaped a substantial reward sixteenth and seventeenth to the nine- for their eminent services. We find that teenth century, have we become so wise their improvements were assailed not only as to have exploded error by our mode of with detraction, but by every form of arriving at truth? Have our successes legal and Parliamentary opposition, and borne a due proportion to our teaching in a few instances even by chicanery and and experience ?
violence. But the confidence thus withIf, as has been already remarked, the held from the originators of the steamopposite of error be necessarily truth, and engine and the railway, has by a natural that of failure, success, our own age has revulsion of popular feeling been often nothing to fear from a comparison with bestowed on imitators who, knowing how the ages of Copernicus and Galileo. We to avail themselves of the tide of opinion, shall hardly be suspected of an excessive endeavor to throw their achievements into addiction to authority, to empty logical the shade by carrying out their principles distinctions, nor of an antipathy to experi- to greater and often extravagant lengths. mental methods. These of course are not Be it ever recollected, that merely mechanithe weak points of the philosophy of our cal ingenuity is one of the commonest entime. They may more properly be thought dowments. In the sixteenth century it deto consist in an extreme opposition to the veloped itself in schemes often absurd and errors of our forefathers producing con- impracticable, almost always speculative trary defects.
A passion for originality, and untried. The stock inventions of the an undue depreciation of the merits of nineteenth (when this doubtful kind of those who have preceded us, and an ex- science has almost degenerated into a altation of slight improvements into sub- trade) are frequently, indeed, foolish and stantive discoveries, are common enough baseless mechanical projects, but still examples of this. But we shall better oftener they are merely simple deductions understand the tendencies of the science from known principles inflated into temof our time if we observe the twofold porary importance by the ingenuity of direction of its expansion. The one re- fortune-hunters. Such applications of sults from the numerous mechanical appli- science begin and end within themselves. cations of science, the other from its theo- They lead to no ulterior progress, because retical refinements. The one tends to they contain no vital spirit.* induce an unreasoning wonder at inordinate exertions of mere brute force, the penning these sentences by a recent correspondent
* Our remarks are confirmed and illustrated whilst other expatiates in subtle mathematical in the Times on the “* Alleged Discovery of the Merefinements. The one places its glory in chanical Utility of Electro-magnetic Engines." A the dominion of man over the stubborn competent authority, Mr. Joule, of Manchester, writconditions of matter; the other diverts a ing in that journal to demonstrate the fallacies of the different class of minds from the more which is applicable to a majority of similar projects.
proposed scheme, concludes with an observation fruitful theories of natural philosophy into " It is humiliating to see how readily the matured
The error opposite to this is to be found evil may be said to extend beyond the rein refinements of theory, either trifling in gion of trifling, for the theorist commonly themselves or destitute of a practical bear- falls into positive mistake. Sound mathing, or else fallacious, because founded on ematics lead to false results if applied to insufficient data. Of course it is impossi- insufficient or wrongly assumed data, and ble to rate too highly the importance of the general public is misled by an array a knowledge of theoretical mechanics, and of proof altogether fallacious and deluof the highly complex mathematical arti- sive. It would not be difficult to cite fices by which it may be applied to ex- even illustrious examples of such errors. plain the laws of nature as in physical These “ follies of the wise ” might figure astronomy, or to anticipate the working in a chapter of the Curiosities of Literaof artificial arrangements as in ship-build- ture, and are really as valueless and pering, in the construction of tubular bridges, nicious as the attempts of illiterate meor in the performance of a clock or a steam- chanics to draw from a machine an unengine. But it is also possible to spend a failing flow of power, or to obtain in the lifetime in the solution of problems which processes of manufacture results incomcan scarcely be more than curious amuse- patible with the known laws of heat, ments. Indeed, it is the mistaken idea electricity, and chemistry.
chemistry. That the that much of the time of mathematicians subtle and intricate forces of nature such and natural philosophers is spent in such as those which we have just named should "curious trifling," which often raises a be misunderstood and misapplied, is insneer at their expense on the part of per-evitable in an age when the real powers sons who are little acquainted with the of science are so amazing that the mere eminently practical nature of the problems strangeness or seeming improbability of a which science resolves. It is indeed (as result is by no means a test of its being Bacon maintained) an eminent criterion of erroneous or the reverse. The mass of our being well employed, that our labor mankind--who in this particular instance shall not terminate in itself
, but be fruit- are nearly as prone as in the days of ful—fruitful of knowledge, or fruitful of Galileo to swear by the authority of some applications. The solution of curious or celebrity, or to be attracted by the splenhighly abstract problems, though to a dor of profitable promises, or to prostrate limited extent a commendable exercise, is their reason and common-sense before an ever to be guarded against when it is val- array of geometric symbols wholly uninued on its own account as a dexterous telligible to them-are but too ready to achievement. In this respect it ranks applaud and to propagate the mistake. with the dexterity of the chess player, and If we now resume the inquiries : Have no higher.
we become so wise as to have exploded In confirmation of this remark it may be error by our mode of arriving at truth? observed that the ablest mathematicians, Have our successes borne a due proportion though they have often commenced their to our teaching and experience ? the ancareer amidst the most abstruse and in- swer to the latter question, at least, must applicable generalizations of the science depend upon another one, namely, whether of quantity, have, with few exceptions, the Art of Discovery is capable of being gradually descended, (as some might call reduced to rule? One very great man, at it,) or as we ought rather to say ascended, all events, thought that it was. to the consideration of definite, concrete, Bacon devoted the most celebrated and and practical questions, than which none important of his writings to define and afford more scope to the most enterpris- explode the errors by which the increase ing student or analyst. Farther, in cases of knowledge was in his time retarded, where the abuse of which we speak has and to systematize a positive method of obtained amongst modern writers, of discovery. In the former part of his task making-to use a homely phrase--the he was, io a great extent, successful ; in facts of nature mere pegs on which to sus- the latter his failure was conspicuous. Not pend festoons of algebraic drapery, the only did he himself not succeed in any
model investigation, but the procedure judgment of an eminent cultivator of science is set which he recommended was not followed aside. Personally he can well afford it, knowing that truth will ultimately triumph; but he regrets by any succeeding natural philosopher. deeply when he sees talent and energy misdirected Looking, however,
rather to the historical through ignorance of established scientific principles." | evidence which now occupies us than to