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THE EARTHLY PARADISE: A POEM. By WILLIAM MORRIS, Author of The Life and Death of Jason. Boston: Roberts Brothers.
THE GOSPEL IN THE TREES: With Pulpit Opinions on Common Things. By ALEXANDER CLARK. Philadelphia: J. W. Daughaday & Co.
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From Tinsley's Magazine.
FROM its hidden source secure,
Through sun and shade, through dusk and
Onward glides the little river.
Through the meadows broad and fair,
And great swans come floating queenly;
Past great towns, whose roar and riot
With whipping and thrashing,
With bustling, and hustling, and justling,
With hurrying, and scurrying, and flurrying,
With sliding, and gliding, and riding, and strid-
With crying, and flying, and shying, and plying,
The ranks quickly thinning,
Bright-sailed boats with youth and maiden; Some faces grow brighter-and some grow for
Thundering paddles flashing back
Bearing all, for work or play,
Hurrying on, through night and day,
And that's how the horses come round at The
Grows stronger and
"They're off! "They are coming!" "Who leads?" "Black and red!"-"No! Green, by a head !” "The Earl!" "No, the Lady!" looks shady!"
To live or to die on!"
"Green Sleeve !" "Restitution!"
Then on they come lashing, and slashing, and
Their colours all flashing like lightning-gleams gashing
The darkness, where, clashing, the thunder is crashing!
THE second reading of Mr. Ewart's Bill introducing the metric system was carried on Wednesday by a vote of 217 to 65, an extraordinarily heavy vote, considering that the majority of the House know no more about the metric system than about the differential calculus. Mr. Ewart proposes that after a certain number of years the French measures shall be introduced bodily, nomenclatures and all. He was opposed by Mr. Beresford Hope on somewhat novel ground. He argued, of course, against the expediency of a change which would greatly embarrass the ignorant and the poor, but also read a letter from Sir John Herschel, asserting that the British whole, more scientific than the French. The standards of measure and weight are, on the English foot is within 1,000th part of an absolute geometrical foot; our English ounce is exactly 1,000th part the weight of a geometrical cubic foot of distilled water at a temperature of water. The benefit of international weights and 72°; and our half-pint is precisely ten ounces of to forcible changes of the kind, unless their utilmeasures is very small, and we altogether object great indeed. ity, as in the matter of decimal coinage, is very
From The Cornhill Magazine.
west. No wonder, therefore, that we went astray when we followed a guide so untrustworthy.
The peculiarity that the magnetic needle does not, in general, point to the north, is the first of a series of peculiarities which we now propose briefly to describe. The irregularity is called by sailors the needle's variation, but the term more commonly used by scientific men is the declination of the
time ago, for 800 years before our era the
THERE is a very prevalent but erroneous opinion that the magnetic needle points to the north. We remember well how we discovered in our boyhood that the needle does not point to the north, for the discovery was impressed upon us in a very unpleasant manner. We had purchased a pocket compass, and were very anxious not, indeed, to test the instru- needle. It was probably discovered a long ment, since we placed implicit reliance upon its indications—but to make use of it as a guide across unknown regions. Not many miles from where we lived lay Cobham Wood, no very extensive forest certainly, but large enough to lose oneself in. Thither, accordingly, we proceeded with three schoolfellows. When we had lost ourselves, we gleefully called the compass into action, and made from the wood in a direction which we supposed would lead us home. We travelled on with full confidence in our pocket guide; at each turning we consulted it in an artistic manner, carefully poising it and waiting till its vibrations ceased. But when we had travelled some As we travel from place to place the dectwo or three miles without seeing any house lination of the needle is found to vary: or road that we recognized, matters as- Christopher Columbus was the first to desumed a less cheerful aspect. We were un-tect this. He discovered it on the 13th of willing to compromise our dignity as "ex- September, 1492, during his first voyage, plorers" by asking the way-a proceeding and when he was six hundred miles from which no precedent in the history of our fa- Ferro, the most westerly of the Canary Islvourite travellers allowed us to think of. ands. He found that the declination, But evening came on, and with it a summer which was towards the east in Europe, passed thunder-storm; we were getting thoroughly to the west, and increased continually as he tired out, and the juvabit olim meminisse travelled westwards. with which we had been comforting our- But here we see the first trace of a yet selves began to lose its force. When at more singular peculiarity. We have said length we yielded, we learned that we had that at present the declination is towards gone many miles out of our road, and we the west in Europe. In Columbus' time it did not reach home till several hours after was towards the east. Thus we learn that dark. How it fared with our schoolfellows the declination varies with the progress of we know not, but a result overtook our-time, as well as with change of place. selves personally, for which there is no The Genius of modern science is a weighprecedent, so far as we are aware, in the records of exploring expeditions. Also the offending compass was confiscated by justly indignant parents, so that for a long while the cause of our troubles was a mystery to us. We now know that instead of pointing due north the compass pointed more than 20° towards the west, or nearly to the quarter called by sailors north-north
ing and a measuring one. Men are not satisfied now-a-days with knowing that a peculiarity exists; they seek to determine its extent, how far it is variable — whether from time to time or from place to place, and so on. Now the results of such inquiries applied to the magnetic declination have proved exceedingly interesting.
We find first, that the world inay be di
of which the needle has a westerly, and over the other an easterly, declination. Along the boundary line, of course, the needle points due north. England is situated in the region of westerly magnets. This region includes all Europe, except the northeastern parts of Russia; Turkey, Arabia, and the whole of Africa; the greater part of the Indian Ocean, and the western parts of Australia; nearly the whole of the Atlantic Ocean; Greenland, the eastern parts of Canada, and a small slice from the northeastern part of Brazil. All these form one region of westerly declination; but singularly enough, there lies in the very heart of the remaining and larger region of easterly magnets, an oval space of a contrary character. This space includes the Japanese Islands, Manchouria, and the eastern parts of China. It is very noteworthy also, that in the westerly region the declination is much greater than the easterly. Over the whole of Asia, for instance, the needle points almost due north. On the contrary, in the north of Greenland and of Baffin's Bay, the magnetic needle points due west, while still further to the north (a little westerly) we find the needle pointing with its north end directly towards the south.
vided into two unequal portions, over one to the south. In fact, it was imagined that the motion of the needle would resemble that of the hands of a watch, only in a reversed direction. But before long observant men detected a gradual diminution in the needle's westerly motion. Arago, the distinguished French astronomer and physicist, was the first (we believe) to point out that "the progressive movement of the magnetic needle towards the west appeared to have become continually slower of late years" (he wrote in 1814), "which seemed to indicate that after some little time longer it might become retrograde." Three years later, namely on the 10th of February, 1817, Arago asserted definitively that the retrograde movement of the magnetic needle had commenced to be perceptible. Colonel Beaufoy at first oppugned Arago's conclusion, for he found from observations made in London, during the years 1817-1819, that the westerly motion still continued. But he had omitted to take notice of one very simple fact, viz., that London and Paris are two different places. A few years later and the retrograde motion became perceptible at London also, and it has now been established by the observations of forty years. It appears from a careful comparison of Beaufoy's observations that the needle In the presence of these peculiarities it reached the limit of its western digression would be pleasant to speculate. We might (at Greenwich) in March, 1819, at which imagine the existence of powerfully mag- time the declination was very nearly 25°. netic veins in the earth's solid mass, coercing In Paris, on the contrary, the needle had the magnetic needle from a full obedience to reached its greatest western digression the true polar summons. Or the compara- | (about 22 1-2°) in 1814. It is rather singular tive effects of oceans and of continents that although at Paris the retrograde momight be called into play. But unfortunately tion thus presented itself five years earlier for all this we have to reconcile views founded than in London, the needle pointed due on fixed relations presented by the earth, north at Paris six years later than in Lonwith the process of change indicated above.don, viz., in 1663. Perhaps the greater Let us consider the declination in England alone.
In the fifteenth century there was an easterly declination. This gradually diminished, so that in about the year 1657 the needle pointed due north. After this the needle pointed towards the west, and continually more and more, so that scientific men, having had experience only of a continual shifting of the needle in one direction, began to form the opinion that this change would continue, so that the needle would pass, through north-west and west,
amplitude of the needle's London digression may explain this peculiarity.
"It was already sufficiently difficult," says Arago, "to imagine what could be the kind of change in the constitution of the globe, which could act during one hundred and fifty-three years in gradually transfering the direction of the magnetic needle from due north to 23° west of north. We see that it is now necessary to explain, moreover, how it has happened that this gradual change has ceased, and has given place to a return towards the preceding state
of the globe." "How is it," he pertinently greatest westerly excursion at eleven, as at asks, "that the directive action of the globe, starting. which clearly must result from the action of Of course, these excursions take place molecules of which the globe is composed, on either side of the mean position of the can be thus variable, while the number, po-needle, and as the excursions are small, sition, and temperature of these molecules, and, as far as we know, all their other physical properties, remain constant ? "
never exceeding the fifth part of a degree, while the mean position of the needle lies some 20° to the west of north, it is clear that the excursions are only nominally eastcrn and western, the needle pointing, throughout, far to the west.
But we have considered only a single region of the earth's surface. Arago's opinion will seem still more just when we examine the change which has taken place in Now if we remember that the north end what we may term the "magnetic aspect" of the needle is that farthest from the sun, of the whole globe. The line which sepa- it will be easy to trace in M. Arago's results rates the region of westerly magnets from a sort of effort on the part of the needle to the region of easterly magnets, now runs, turn towards the sun, not merely when as we have said, across Canada and eastern that luminary is above the horizon, but durBrazil in one hemisphere, and across Rus-ing his nocturnal path also. sia, Asiatic Turkey, the Indian Ocean, and We are prepared, therefore, to expect West Australia in the other; besides having that a variation having an annual period an outlying oval to the east of the Asiatic shall appear, on a close observation of our Continent. Now these lines have swept suspended needle. Such a variation has round a part of the globe's circuit in a most singular manner since 1600. They have varied alike in direction and complexity. The Siberian oval, now distinct, was, in 1787, merely a loop of the eastern line of no declination. The oval appears now to be continually diminishing, and will one day probably disappear.
We find here presented to us a phenomenon as mysterious, as astonishing, and as worthy of careful study as any embraced in the wide domains of science. But other peculiarities await our notice.
been long since recognized. It is found that in the summer of both hemispheres, the daily variation is exaggerated, while in winter it is diminished.
But besides the divergence of a magnetized needle from the north pole, there is a divergence from the horizontal position, which must now claim our attention. If a non-magnetic needle be carefully suspended so as to rest horizontally, and be then magnetized, it will be found no longer to preserve that position. The northern end dips very sensibly. This happens in our hemisIf a magnetic needle of suitable length be phere. In the southern it is the southern carefully poised on a fine point, or, better, end which dips. It is clear, therefore, that be suspended from a silk thread without if we travel from one hemisphere to the torsion, it will be found to exhibit each day other we must find the northern dip of the two small but clearly perceptible oscilla- needle gradually diminishing till at some tions. M. Arago, from a careful series of point near the equator the needle is horiobservations, deduced the following re-zontal, and as we pass thence to southern sults:
At about eleven at night, the north end of the needle begins to move from west to east, and having reached its greatest easterly excursion at about a quarter-past eight in the morning, returns towards the west to attain its greatest westerly excursion at a quarter-past one. It then moves again to the east, and having reached its greatest easterly excursion at half-past eight in the evening, returns to the west, and attains its
regions a gradually increasing southern inclination is presented. This has been found to be the case, and the position of the line along which there is no inclination (called the magnetic equator) has been traced around the globe. It is not coincident with the earth's equator, but crosses that circle at an angle of twelve degrees, passing from north to south of the equator in long. 3° west of Greenwich, and from south to north in long. 187° east of Greenwich. The form