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of the line is not exactly that of a great circle, but presents here and there (and especially where it crosses the Atlantic) perceptible excursions from such a figure.
At two points on the earth's globe the needle will rest in a vertical position. These are the magnetic poles of the earth. The northern magnetic pole was reached by Sir J. G. Ross, and lies in 70° N. lat., and 263° E. long., that is, to the north of the American continent, and not very far from Boothia Gulf. One of the objects with which Ross set out on his celebrated expedition to the Antarctic Seas was the discovery if possible of the southern magnetic pole. In this he was not successful. Twice he was in hopes of attaining his object, but each time he was stopped by a barrier of land. He approached so near, however, to the pole, that the needle was inclined at an angle of nearly ninety degrees to the horizon, and he was able to assign to the southern pole a position in 75° S. lat., 154° E. long. It is not probable, we should imagine, that either pole is fixed, since we shall now see that the inclination, like the declination of the magnetic needle, is variable from time to time, as well as from place to place; and in particular, the magnetic equator is apparently subjected to a slow but uniform process of change.
Arago tells us that the inclination of the needle at Paris has been observed to diminish year by year since 1671. At that time the inclination was no less than 75°; in other words, the needle was inclined only 15° to the vertical. In 1791 the inclination was less than 71°. In 1831 it was less than 68°. In like manner the inclination at London has been observed to diminish, from 72° in 1786 to 70° in 1804, and thence to 68° at the present time.
It might be anticipated from such changes as these that the position of the magnetic equator would be found to be changing. Nay, we can even guess in which way it must be changing. For, since the inclination is diminishing at London and Paris, the magnetic equator must be approaching these places, and this (in the present position of the curve) can only happen by a gradual shifting of the magnetic equator from east to west along the true equator. This motion has been found to be really taking place. It is supposed that the movement is accompanied by a change of form; but more observations are necessary to establish this interesting point.
Can it be doubted that while these changes are taking place, the magnetic poles also are slowly shifting round the true pole? Must not the northern pole, for in
stance, be further from Paris now that the needle is inclined more than 23° from the vertical, than in 1671, when the inclination was only 15°? It appears obvious that this must be so, and we deduce the interesting conclusion that each of the magnetic poles is rotating around the earth's axis.
But there is another peculiarity about the needle which is as noteworthy as any of those we have spoken about. We refer to the intensity of the magnetic action, the energy with which the needle seeks its position of rest. This is not only variable from place to place, but from time to time, and is further subject to sudden changes of a very singular character.
It might be expected that where the dip is greater, the directive energy of the magnet would be proportionably great. And this is found to be approximately the case. Accordingly the magnetic equator is very nearly coincident with the "equator of least intensity," but not exactly. As we approach the magnetic poles we find a more considerable divergence, so that instead of there being a northern pole of greatest intensity nearly coincident with the northern magnetic pole, which we have seen lies to the north of the American continent, there are two northern poles, one in Siberia nearly at the point where the river Lena crosses the Arctic circle, the other not so far to the north-only a few degrees north, in fact, of Lake Superior. In the south, in like manner, there are also two poles, one on the Antarctic circle about 130° E. long. in Adelie Island, the other not yet precisely determined, but supposed to lie on about the 240th degree of longitude, and south of the Antarctic circle. Singularly enough there is a line of lower intensity running right round the earth along the valleys of the two great oceans, passing through Behring's Straits and bisecting the Pacific on one side of the globe, and passing out of the Arctic Sea by Spitzbergen and down the Atlantic on the other."
Colonel Sabine discovered that the intensity of the magnetic action varies during the course of the year. It is greatest in December and January in both hemispheres. If the intensity had been greatest in winter one would have been disposed to have assigned seasonal variation of temperature as the cause of the change. But as the epoch is the same for both hemispheres we must seek another cause. Is there any astronomical element which seems to correspond with the law discovered by Sabine? There is one very important element. The posi tion of the perihelion of the earth's orbit is such that the earth is nearest to the sun on
about the 31st of December or the 1st of January. There seems nothing rashly speculative, then, in concluding that the sun exercises a magnetic influence on the earth, varying according to the distance of the earth from the sun. Nay, Sabine's results seem to point very distinctly to the law of variation. For, although the number of observations is not as yet very great, and the extreme delicacy of the variation renders the determination of its amount very difficult, enough has been done to show that in all probability the sun's influence varies according to the same law as gravity - that is, inversely as the square of the distance.
That the sun, the source of light and heat, and the great gravitating centre of the solar system, should exercise a magnetic influence upon the earth, and that this influence should vary according to the same law as gravity, or as the distribution of light and heat, will not appear perhaps very surprising. But the discovery by Sabine that the moon exercises a distinctly traceable effect upon the magnetic needle seems to us a very remarkable one. We receive very little light from the moon, much less (in comparison with the sun's light) than most persons would suppose, and we get absolutely no perceptible heat from her. Therefore it would seem rather to the influence of mass and proximity that the magnetic disturbances caused by the moon must be ascribed. But if the moon exercises an influence in this way, why should not the planets? We shall see that there is evidence of some such influence being exerted by these bodies.
More mysterious if possible than any of the facts we have discussed is the phenomenon of magnetic storms. The needle has been exhibiting for several weeks the most perfect uniformity of oscillation. Day after day the careful microscopic observation of the needle's progress has revealed a steady swaying to and fro, such as may be seen in the masts of a stately ship at anchor on the scarce-heaving breast of ocean. Suddenly a change is noted; irregular jerking movements are perceptible, totally distinct from the regular periodic oscillations. A magnetic storm is in progress. But where is the centre of disturbance, and what are the limits of the storm? The answer is remarkable. If the jerking movements observed in places spread over very large regions of the earth-and in some well-authenticated cases over the whole earth-be compared with the local time, it is found that (allowance being made for difference of longitude) they occur precisely at the same instant. The magnetic vibrations thrill in
one moment through the whole frame of our earth!
But a very singular circumstance is observed to characterize these magnetic storms. They are nearly always observed to be accompanied by the exhibition of the aurora in high latitudes, northern and southern. Probably they never happen without such a display: but numbers of auroras escape our notice. The converse proposition, however, has been established as an universal one. No great display of the aurora ever occurs without a strongly marked magnetic storm. Magnetic storms sometimes last for several hours or even days.
Remembering the influence which the sun has been found to exercise upon the magnetic needle, the question will naturally arise, has the sun anything to do with magnetic storms? We have clear evidence that he has.
On the 1st of September, 1859, Messrs. Carrington and Hodgson were observing the sun, one at Oxford and the other in London. Their scrutiny was directed to certain large spots which, at that time, marked the sun's face. Suddenly, a bright light was seen by each observer to break out on the sun's surface and to travel, slowly in appearance, but in reality at the rate of 7,000 miles in a minute, across a part of the solar disc. Now it was found afterwards that the self-registering magnetic instruments at Kew had made at that very instant a strongly marked jerk. It was learned that at that moment a magnetic storm prevailed at the West Indies, in South America, and in Australia. The signalmen in the telegraph stations at Washington and Philadelphia received strong electric shocks; the pen of Bain's telegraph was followed by a flame of fire; and in Norway the telegraphic machinery was set on fire. night great auroras were seen in both hemispheres. It is impossible not to connect these startling magnetic indications with the remarkable appearance observed upon the sun's disc.
But there is other evidence. Magnetic storms prevail more commonly in some years than in others. In those years in which they prevail most frequently, it is found that the ordinary oscillations of the magnetic needle are more extensive than usual. Now when these peculiarities had been noticed for many years, it was found that there was an alternate and systematic increase and diminution in the intensity of magnetic action, and that the period of the variation was about eleven years. But at the same time a diligent observer had been
recording the appearance of the sun's face from day to day and from year to year. He had found that the solar spots are in some years more freely displayed than in others. And he had determined the period in which the spots are successively presented with maximum frequency to be about eleven years. On a comparison of the two sets of observations it was found (and has now been placed beyond a doubt by many years of continued observation) that magnetic perturbations are most energetic when the sun is most spotted, and vice versa.
For so remarkable a phenomenon as this none but a cosmical cause can suffice. We can neither say that the spots cause the magnetic storms nor that the magnetic storms cause the spots. We must seek for a cause producing at once both sets of phenomena. There is as yet no certainty in this matter, but it seems as if philosophers would soon be able to trace in the disturbing action of the planets upon the solar atmosphere the cause as well of the marked period of eleven years as of other less distinctly marked periods which a diligent observation of solar phenomena is beginning to educe.
From The Saturday Review. KIRK'S CHARLES THE BOLD.*
MR. KIRK seems to us to have used the five years which have elapsed since the publication of his first two volumes † to advantage. He has improved as a writer. There are still some blemishes in language, and some unaccountable slips of carelessness. But he is less inclined to take liberties with English, and though there is still a tendency to heighten effect by florid touches, and to indulge in flings of doubtful irony and sarcasm, his taste in these matters is more manly and sober. He tells his story with greater directness and strength of arrangement and connexion. And the work bears the marks more than ever of careful and honest labour. The Swiss archives, it appears, are full of original materials relating to the war with Burgundy, much of which has been published in the collections of historical documents in which Switzerland is not behind the rest of the world. These Mr. Kirk has used, but he has besides explored manuscript sources for himself, and among his chief and most important authorities are the original German and Latin letter-books of the Government of Berne, with
The History of Charles the Bold, Duke of Burgundy. By John Foster Kirk. Vol. III. London: John Murray. 1868.
↑ See Saturday Review, December 26, 1863.
the corrections, erasures, and interlineations of the day, to which he refers on almost every page. He has also examined the collections, now become accessible, of the despatches of the Venetian and Milanese agents. Where he seems least strong in regard to contemporary evidence is in his references to French papers.. It does not appear that he has explored in the French libraries as he has done among the Swiss. But the Swiss records contain the most important portion of the evidence wanted. They throw as much light on the policy of Louis as on that of the Confederates.
And in this portion of the work, as Mr. Kirk has treated his subject, Louis and the Swiss Confederates are really the principals, and Charles occupies but a subordinate place. That is to say, he is the person whose destruction is the object and governing purpose of a great and successful alliance, carried out through difficulties and risks with unflinching craft, energy, and resolution on the part of the allies; and the schemes and bargainings and arts of the destroyers occupy the foreground of the narrative, while the share of Charles himself in it sinks for the most part from its first prominence into that which belongs to a passive and hopelessly defensive attitude. All through this third volume Charles appears as the object of unprovoked and unrelenting attack from the terrible Swiss, to whom he had done no wrong nor given any cause for fear. His ambitious schemes, which alarmed Europe, are almost put out of sight and taken to be at an end, and he is fighting, not for empire, but desperately for very life. Such a way of representing the matter is borne out by the facts of the moment, but it is apt to leave an impression in Charles's favour which is not quite the fair one. To look at the Swiss war by itself, without connexion with Charles's previous career and actions, is as partial a way of considering it as it would be to regard Napoleon's defence of France in 1814, or even his German campaign of Leipsic, without reference to the antecedents of the Russian war and the Imperial tyranny over Europe. When a man's pride, cruelty, and wild desires of aggrandizement have thoroughly alarmed the world, and infused force and the determination to have done with him into formidable leagues, the advantages which his enemies take of him, their unscrupulous and implacable activity, and possibly the heroism and dignity of his resistance to hard conditions and terrible odds, ought not to make the historian forget that he is relating the course, not merely of a great fall, but of a just retribution.
of co-operation and joint action, he speaks with the admiration which a republican might naturally feel for such early fruits of freedom; but his admiration is qualified by his sense of truth, which compels him to see in the Swiss a shameless greediness, a recklessness of justice and the rights of others, a daring readiness for intrigue and treachery, and a savage liking for butchery as well as war, which places the rough mountaineers quite on a level with their more refined contemporaries of the turbulent cities or the feudal castles.
Mr. Kirk writes of the three chief sub- some very ticklish and critical stroke of jects of his history with an undisguised cleverness had, after great risks, succeeded. mixture of feelings. He dislikes and con- The heroes of the volume are the Swiss; demns the cause of which Charles was the and of the part they played in bringing representative, and certainly he does not about the catastrophe, and shattering the conceal Charles's personal faults; but he beginnings of a new "Middle Kingdom" gives him credit for more sagacity and which, if it had come into existence, would statesmanship than has been usually al- have altered the map and the history of Eulowed him, and he cannot keep back the rope, he makes as much account as any presympathy which naturally arises for a man vious writer, and with the greater right of who suffers what, it may be, he has brought clearer and more exact knowledge. Of the on himself and perhaps deserves, yet who astonishing apparition, in the midst of arissuffers it at the hands of those towards tocratic Europe, not only of Swiss valour whom at least he is guiltless. Mr. Kirk, and matchless superiority in the field, but himself a man of the present, and hating of the robustness and public spirit of their the selfish stupidity and brutality of media- democratic societies, of their tenacity of val feudalism, yet regards Charles person-purpose and high temper, and their power ally with the admiration which people cannot help feeling for high spirit and gallantry, and with the compassion with which he would regard a grand and magnificent gentleman, noble in temper and lofty in his thoughts, who is outwitted and brought to the ground by cheating money-lenders and low attorneys. Indeed, his respect for Charles as a gentleman inclines him to judge too favourably of Charles's honour and his intelligence. Charles was one of those high and chivalrous people who can yet on occasion do the most dishonourable things without remorse. And his statesmanship consisted in conceiving vast and imposing schemes, for which his position gave him the greatest advantages, without having the patience either to think out his plans or prepare the means, and without the self-control and temper to inspire confidence, and to attach to himself supporters like the great communities of the Netherlands, or Ministers like Commines. Europe has suffered as well as gained by the consolidation of France, which was the triumph of Louis. If Charles had founded his projected Middle Kingdom, it would probably have been, in spirit and policy, but another Austria, squeezed up between Germany and France.
Mr. Kirk fully appreciates Louis's utter unscrupulousness and personal worthlessness, his want of all nobility of character and real greatness of purpose. But in his steady policy, though prompted by selfishness and carried on by craft and treachery, he sees the winning game of modern ideas of Government against the decaying cause of feudal anarchy; and he watches, with a mixture of amusement and admiration, the King's humour, his indifference to all that dazzles the vulgar, his resolute courage, the fruit of strong reason and clear insight rather than of temperament, and his uncontrollable sallies of delight and triumph when
Charles, as Mr. Kirk insists with great earnestness, had never done any harm to the Swiss who were the instruments of his ruin, and whose patriotism and gallantry in their struggle with him have been so loudly, and, as Mr. Kirk thinks, so lightly and thoughtlessly extolled. It is the object of his third volume to show in detail, and by the evidence of the Swiss themselves, that the ordinary romantic view of the glory of Granson and Morat is one of the most absurd of historical fallacies. They were extraordinary and signal victories, but they were the victories of the side of wrong. He writes to lay bare this imposture. Charles, he maintains, was entirely guiltless as regards the Swiss Cantons, of which Berne was the leader. However threatening he might be to Germany and the Rhine, though even in this there was exaggeration, to the Eight Cantons he had done nothing to alarm or provoke them. He had been their friend, and had shown no signs of changing. It was they who altered, and became the aggressors. And the history of their aggression was that they were bought and hired by Louis XI. to do his work against his dreaded neighbour. Louis XI. intrigued and bargained with the chiefs of Berne; and in return for subsidies of French gold, they undertook to pick a quarrel with Charles, to commit their confederates to it, and to keep
quent, and more emphatic communications with Louis XI. of France, they avered that it was at his request and on his behalf that they had suasions and the promises of his ambassadors, taken up arms, that they had yielded to the perand that, without the pledges and assurances thus given, they would not have been willing, never could have been induced, to embark in a war against the Duke of Burgundy.
the head of a different race and nation, with
it up as long as Louis paid the stipulated their alliance with Austria, and their obligations sum, of which the largest part went to as an integral part of the German race and ConBerne, and of that the largest part to the federation. But in their more private, more frepopular leaders of Berne. Charles's part in the war was purely defensive. Wantonly attacked on his frontier in the Jura, attacked in the territory of his ally the Duchess of Savoy, his invasion of Switzerland was only his answer to the devastating and ferocious inroads of neighbours to whom he knew that he had given no cause of complaint, and whom we know to have been in the pay of his deadly enemy. When the To reconcile these statements, it is necessary Swiss had astonished the world by their to recollect that the treaty with Austria, which great victories on their own soil, and had had reminded the Swiss of their allegiance to the hunted Charles to death before Nancy, they Empire and furnished them with a pretext for were able, on the strength of their unques- their proceedings, was itself a contrivance of the tionable success, to persuade the world into French King, one of a long series of manoeuvres a belief also of the goodness of their cause. all conducted with the same object, and through Mr. Kirk leaves them the praise of their exthe same agency. Entered into with reluctance traordinary daring and skill. But he ut- by most of the Cantons, by scarcely more than one of them with a hostile design against the terly refuses them the merit of anything else Burgundian prince, it had lacked the inherent that gives lustre to victory. The men upon force to accomplish of itself the purpose with whose spears the chivalry of Burgundy was which it had been devised. During several broken were the greedy and merciless fight-months, while Alsace was a scene of hostilities, ers in a quarrel for which they cared noth- the Swiss remained passive. Their participation ing, the tools of a few cold-blooded wire- began at the moment when they had consented pullers at Berne, who traded in the blood to another alliance, a closer and more confidenof their countrymen, and did as much as tial alliance than they had formed with Austria Louis XI. was willing to pay for. Granson or with any other State-an alliance, namely, and Morat are very different from Morgar- with Louis himself; one which had, it is true, no ten and Sempach. They were the first affiance with their national sentiments or policy, steps in that career of mercenary warfare but which acted directly upon their instincts as and alliances which made the Swiss name a a people and their interests as individuals, diffusbyword for everything that was brave and ing its effects through every quarter of their everything that was venal; which, accord-country and over all their subsequent history. Unless these facts be entirely dismissed from ing to a computation made in 1715, had up consideration -unless mere theory be substito that time cost Switzerland, in the service tuted for a recital of facts-we must conclude of France alone, 700,000 lives, and had that the war had its real origin, not in the combrought in, as their price, 1,146,868,623 plications in which Charles had recently become francs; which till lately exhausted the coun-involved with certain of the German States and try, and retarded its progress and civilization; and which, even now that it is stopped, has left its demoralizing effects on the population of the Cantons:
with the Empire itself, but in his old and ceaseless rivalry with the King of France. That the Swiss were to some extent imbued with the feeling of German nationality is true. This was one of the springs touched upon, and it no doubt operated to deceive some and to enable others to deceive themselves. But it was not their sympathies with the German race, nor their fidelity to the Empire, that led them to tear up their ancient treaties, and so fall upon their oldest ally. Nay, that feeling was soon found to be antago nistic to the new policy they had adopted. The German sentiment, in the degree to which it prevailed, proved a hinderance to the prosecution of the war; and in proportion as the war was prosecuted the German sentiment was weakened. In every phase of the contest, and in all its re
Explicitly denying that their own territory had been an object of aggression, never alleging any provocation of whatever nature received by themselves, never intimating any belief that the rights or the honour of the Confederacy had been involved in the origin of the contest; they, on the contrary, lost no opportunity of proclaiming that they had entered the arena in support of a cause with which as a nation they had no direct or personal concern. There was, however, an apparent discrepancy in their statements, both as to the motives by which they had been swayed and as to the party for whom they ap-sults, we shall find confirmation of what we peared as champions. In their public manifesto, and on certain convenient occasions, they set forth, as their grounds of action, the summons addressed to them by the head of the Empire,
learn from the evidence in the case and from the avowals of the parties—namely, that it was undertaken at the instigation of France, for the interest of France, and in the pay of France.