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a flash. Her ponies were restive ; they Jesus, Lover of my soul – swerved, close upon Russell. Stephen That old story of a Saviour. I can be raised his arm to draw him out of the lieve it, when I think of Eily. What way. But in the same instant Mira

did she say? You've not tried that, lashed them maliciously, ignoring the

Russell.' passers-by. They dashed forward,

sus — Jesus -L trampling Russell under their hoofs.

of my soul, The wheels rolled over him and flew

Let me to Thy bosom fly, The golden hair which had excited I hadn't tried it then. But I'll try it Stephen's disdain shone, as the red now. I'm going - I'm going — to make glow kindled it, from the dust.

a fresh start and try it now."

The large eyes opened with the liquid Stephen, am I dying ?” he said smile of their boyhood. Russell was faintly.

gone. He had just awakened in his bed at the hospital. The surgeon signed to Stephen from his post on the other side. IT was night, and the stars were

“ Would you like to see any one ?” shining. asked Stephen, bending lower.

“Eily," said Stephen musingly, “do “No-I won't frighten her. I was you realize that I was literally dying for telling you, when - I had taken my you? I have always laughed that kind passage to New Zealand. Ask at the of thing to scorn. Yet it was true.” office — the Southern Neptune - you'll “Ah, Stephen ! if I had known from find it true. I'm glad now. Oh, I'm the first, perhaps But you were glad I made up my mind !"

always so hard and so strong.” 6. There was a message.

“I had one weak place, though, remember ?"

and that was mortal. Achilles' heel ! “Ah! a message to Eily. Yes, tell Never mind! You have brought me her that I did as she wished. I con- back to life. Now you must help me in quered, after all. I didn't go. She'll another life - which I have only just know what I mean. Tell her I didn't begun. Perhaps I should never have go. Tell her that I tore up the note, begun it, Eily, but for you.". and sent it back in an envelope, without “ What do you mean ?” asked Eily, a word, to the hotel. And then I all unconscious. thought, if I stayed in England, the “I'll tell you some time. Russell same would come over again. And I re- knows. Ah, darling ! darling!” membered my father's land. I thought His eyes, as she gazed down into - if I went and worked hard

them, were full of adoration. His counThe house-surgeon stooped to wipe tenance, once so cold, seemed transfigaway great drops gathering on the fore- ured. head.

Eily, look!

do you recognize our “I broke my promise. Ask Eily all star ? Do you remember my telling about it.” He turned wistfully towards you that you would never draw Russell Stephen. "I was ashamed to go and up there?wish her good-bye. I meant to write He stopped suddenly ; he thought of by the pilot. I meant to say, “ Eily, I his dream, of Eily's face in those rádishould have been lost but for you.' ant heights. An old prophecy sounded

“I will say it instead," returned in his ears. Was it Russell's voice, Stephen. The glazing eyes closed in answering far away ? peace.

"THEY THAT BE WISE SHALL SHINE “Would you wish to see the chap- AS THE BRIGHTNESS OF THE FIRMAlain ? " the house-surgeon asked. MENT, AND THEY THAT TURN MANY But Russell did not hear:

TO RIGHTEOUSNESS AS THE STARS FOR" Eily's hymn," he murmured ; | EVER AND EVER.66 what was it ?

E. CHILTON..

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RECENT SCIENCE.

I.

:

From The Nineteenth Century. stands upright in higher latitudes

such was the simplest expression of

Dove's theory given in text-books. 1 DURING the last thirty years the data Under this provisory hypothesis meof meteorology have been accumulated teorology made an immense progress, with a very great rapidity, and the chief and some five-and-thirty years ago, desideratum of the moment is, to con- Leverrier in France, and Fitzroy in this struct with these data such a general country, ventured for the first time to theory of the circulation of the atmo- foretell weather twenty-four hours in sphere as would embody the distribution advance, or at least to send out warnof heat, pressure, moisture, and winds ings as to the coming storms. This over the surface of the earth, and rep- bold step brought meteorologists face to l'esent them as consequences of well: face with a quite new problem. From established mechanical laws. The old the air-pressure, the temperature, the provisory hypothesis of atmospheric moisture, and the winds observed at a circulation, advocated by Hadley in certain hour of the day at various spots 1735, and further elaborated by Dove and telegraphed to a central station in our century, can be held no more, they had to infer the next probable and a new theory has become of abso- state of weather. So, leaving aside the lute necessity.

great problems of atmospheric circulaWe all have learnt Dove's theory at tion, they directed their attention to the school, even though we often found it changes of weather rather than to the difficult to understand. The air, greatly causes of the changes.2 For this purheated on or near the equator, rises in pose purely empirical laws were of great the same way as it rises in the summer value. When the meteorologist saw on over a sunburnt plaiu. On reaching the a weather-chart a region of low atmohigher strata of the atmosphere it flows spheric pressure, with winds blowing towards the poles, but, owing to the in spirals round aud towards its centre, speed of rotation which it has acquired he named it, by analogy with real in the lower latitudes, it is deflected — cyclones, cyclonic disturbance" to consider the northern hemisphere or " cyclone,” giving the name of only — to the right, and blows in the anti-cyclone” to the region of high upper strata as a current from the atmospheric pressure — and he studied south-west. To compensate this flow, the tracks of both disturbances in their air rushes on the earth's surface advance across the oceans and the contowards the equator, and as it also is tinents. He did not inquire for the deflected from its course by the same moment into the causes of the disturbinertia of rotation, it appears in the ances; he took them as facts, and, tropics as a trade-wind blowing from following Buys Ballot's law, he said the north-east. However, the upper that the wind will blow as a rule from warm current does not flow all the way the region of high barometric pressure to the pole in the upper regions; it is the anti-cyclone) to the region of low gradually cooled down, and in about the pressure (the cyclone), with a certain thirtieth degree of latitude it begins to deflection to the right or to the left. descend to the earth's surface, where it Immense researches were made to study meets with the cold polar current. A the routes followed by the centres of struggle between the two winds ensues, barometrical minima, and we now have and it lasts until they make a temporary splendid atlases showing the normal peace by blowing side by side, or one tracks of cyclones across the Atlantic above the other; the struggle giving Ocean, over Europe and the States, in origin to storms and to changes of wind which are fully analyzed in Dove's the- 1 E. E. Schmid, Lehrbuch der Meteorologie, ory. A rope without end rolling over Leipzig, 1860, p. 568.

? See W. Bezold's short sketch of meteorological two pulleys, one of which lies horizon- progress in Sitzungsberichte der Berlin Akademie tally near the equator and the other. I der Wissenschaften, 1890, ii. 1295, 89.

4255

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LIVING AGE.

VOL. LXXXII.

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Japan, in the Indian Ocean, and so on, more and more evident, especially since at various seasons of the year. With the movements of clouds began to be these empirical data meteorologists systematically studied and observatories attained such a perfection in their were erected on high mountains; and weather forecasts that in tive cases out this wind remained unexplained in of six their previsions are now correct, Dove's theory, while in Maury's scheme while the coming gales are even fore- of atmospheric circulation, which is told with a still greater accuracy.

still in great vogue in our schools, However, the very progress achieved there was even substituted for it a curdemonstrated the necessity of a more rent in an opposite direction, which thorough knowledge of the too much does not exist, and which Maury himneglected upper currents of the atmo- self could not account for.8 An entire sphere. In Dove's scheme, the upper revision of the subject was thus necesequatorial current, after part of it had sary, and this revision has been done been sent back to the equator, was eu- by the American meteorologist Ferrel, tirely abandoned to itself, to make its in a series of elaborate works which way as best it could against the opposed are only now beginning to receive from polar winds; but the existence of a meteorologists the attention they fully strong, nearly permanent, and relatively deserve. warm upper wind blowing towards the Ferrel's theory is based upon consideast in our latitudes - which was only erations as to the laws of motion of probable thirty years ago 2— became liquids and gases of different densities.

1 Besides the earlier works of Ley (Laws of the If the whole atmosphere were equally Winds Prevailing in Western Europe, Part I. 1872) | heated in all its parts, and at full rest, and Köppen (Wissenschaftliche Ergebnişse aus the air would be disposed in horizontal der monatlichen Uebersichten des Wetters, 187378), we have now the splendid work of W. J. Van layers, of greater density at the botBebber, which embodies the tracks of all cyclones tom, and of decreasing density towards in Europe for the last fifteen years (Die Zugstrassen the top. Considering some part only of der barometrischen Minima, für 1875-90), the researches of Blanford, S. E. Hill, and Elliot in the the atmosphere, from pole to equator, "Indian Meteorological Memoirs ” and “Cyclone and neglecting the curved surface of Memoirs,” Part IV. (published by the Meteoro- the earth, we should thus have somelogical Department of India), the work of E. Knipping for Japan, in " Annual Meteorological Report thing analogous to a trough filled with for 1890,” Part II. Appendix, and several excellent layers of different liquids. If one end

of the trough were now warmed, and 2 Observations in Siberia, namely, at the graphite works on Mount Alibert, at a height of eight thou- the other end were cooled, the layers sand feet (520 N. lat.), were especially conclusive. would be horizontal no more. They Alibert's observations, buried in the Russian would be inclined, but in two different Trudy of the Siberian expedition, proved the existence of a nearly permanent W. and W. N. W. wind ways; the lower ones would be inon the top of the peak, and they showed at the clined towards the warm part, while in same time that the average yearly temperature on the upper layers the inclination would the top of the peak was by some fourteen to eigh

be the reverse. A full circuit of the teen Fahrenheit degrees higher than it otherwise ought to be. When I visited the then abandoned lighter liquids flowing one way on `the mine in 1864, and saw the peak dominating all sur- surface, and of heavier liquids flowing rounding mountains, and could judge of the force of the west wind from the immense works accom

the other way on the bottom, would plished to protect the road which was traced on thus be established. The same would the western side of the peak, I could not refrain happen in our atmosphere with the from explaining the extraordinarily great height of the snow-line in east Siberia by the existence of lighter, warm currents and the heavier, a relatively warm equatorial current blowing with cold currents if the earth had no rotaa great force at a height of from eight thousand to tion on its axis. But it rotates - the ten thousand feet in a latitude of 520 N. Later on solid globe as well as its gaseous envethe observations which I brought from the Voznesensk mine (60° N., altitude 2,620 feet) induced lope — and this modifies the whole cirmy friend Ferd. Müller, who calculated those ob- culation. The air which flows from the servations, to conclude that in higher latitudes the same current descends still lower to the earth's 3 See James Thomson's paper “On the Grand surface, and still maintains some of its initial Currents of the Atmosphere,” in Philosophical

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Transactions, A. 1892, p. 671.

warmth,

equator to the poles maintains, not its parts to the test of both observation velocity of rotation, as has been hith- and mathematical analysis. By the end erto taught, but its energy of rotation, of his life (he died in 1891) he embodied which means that it obeys the law of his theory in a well-written and sugpreservation of areas ; therefore, when gestive popular work, which fully deit is transported from the equator to a serves being widely known. All taken, higher latitude it is endowed (in the his views so well agree with the facts northern hemisphere) with a much relative to the movements of the atmogreater eastward velocity than if it sphere, and they give such a sound simply maintained its speed of rotation. method for further investigation, that On the other side, the air which is flow- they are sure to become for some years ing from the higher latitudes towards to come the leading theory of meteorolthe equator also obeys the same law ogy. They already have given a strong and acquires a westward velocity, but impulse to theoretical research, anil much smaller than the eastward ve- have created a whole literature in Auslocity of the former ; this is why the tria and Germany: 4 west winds have such a preponderance Another theory of the general circuin our latitudes. Moreover, in virtue lation of the atmosphere which is also of the centrifugal force, all masses of awakening a good deal of interest air moving in any direction — not only among physical geographers was pronorth or south, but also due west or pounded in 1886 by Werner Siemens, east are also deflected to the right in and further developed by him in 1890.5 the northern hemisphere, and to the

4 Roth has already abandoned the mathematical left in the southern hemisphere.2 Con-objections he had raised against Férrel's theory in sequently the air flows in great spirals the Wochenschrift für Astronomie, 1888. The obtowards the poles, both in the upper against the “ density surfaces ” have been answered

jections raised by Teisserenc du Bort and Supan strata of the atmosphere and on the by Professor Davis in Science, and are not shared earth's surface beyond the thirtieth de- by the most prominent meteorologists. And the

mathematical analysis of Professor Waldo, Sprung gree of latitude ; while the return cuir- (the author of the well-known “Treatise of Meterent blows at nearly right angles to the orology"), M. Möller, and Pernter has further above spirals, in the middle strata as confirmed the accuracy of the theory. So also

Hildebrandsson's observations of upper clouds also on the earth's surface, in a zone (Annuaire de la Société météorologique de France, comprised between the parallels 30° N. xxxix. 338), Teisserenc du Bort's high-level isobars, and 30° S.8

and Guaran de Trommelin's researches relative to Such are, very briefly stated, the coast winds. The transport of the Krakatoa dust

and Abercromby's observations of clouds having leading features of the theory which rendered the existence of an upper east current Ferrel laboriously worked out during very probable on the equator, Pernter has mathethe last thirty years, submitting all its matically deduced from Ferrel's theory the exist

ence of such a current in a belt 4° 45' wide on

both sides of the equator, and he therefore has 1 Full tables giving the eastward (or westward) withdrawn the restrictions he had previously made velocities for each latitude, under the two different in a lecture (published in Nature, 1892, xlv. 593) in hypotheses, have been calculated for the Meteoro- favor of Siemens' views. It must be added tbat logische Zeitung, 1890, pp. 399 and 420.

the idea of three superposed currents blowing in 2 Ferrel seems not to have been aware that the spirals may have been suggested to Ferrel by a same bad been demonstrated, by R. Lenz, for rivers communication of James Thomson to the British (about the year 1870) in a discussion of Baer's law, | Association in 1857. Such was, at least, the claim applied to the Amu River, in the "Mémoires” of raised and developed at some length by the Glasthe St. Petersburg Academy.

gow professor before the Royal Society in a 3 Wm. Ferrel, “A Popular Treatise on Winds, Bakerian lecture, now published in the “ Transaccomprising the General Motion of the Atmosphere, tions" (A. 1892, pp. 653-685). Though Thomson's Monsoons, Cyclones, Tornadoes, Waterspouts, paper was never published, and only given in a Hailstorms, etc.” New York (Wiley), 1889. See very short abstract without a diagram (the diagram also analysis of it by W. M. Davis (in Science, xv., in the “Transactions” is now published for the p. 142 ; translated in Meteorologische Zeitung, 1890 ; first time), the few lines in which his theory was Literaturbericht, p. 41), who gave the best diagram stated (British Association Reports, Dublin, 1857, of circulation according to Ferrel's theory, and by pp. 38, 39) contained the idea clearly expressed. H. F. Blanford in Nature, xli. 124. A full bibliog- It is certainly a matter of great regret that James raphy of Ferrel's works was given after his death Thomson has not returned to this subject. in the American Meteorological Journal, October, 5 “Ueber die Erhaltuug der Kraft im Luft

meere,” in “Sitzungsberichte der Berlin Akademie

1901.

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Siemens did not consider that air might| must arise in this case, in the same way flow down the density surfaces, as sup- as they are formed on the sea. The posed by Ferrel and Helmholtz, and upper current, if it is inclined towards admitted by many meteorologists, and the earth's surface (as is often the le maintained that the source of the case), must originate in the lower curenergy required for all disturbances of rent, immense aerial waves rolling at a equilibrium in the atmosphere must be great speed. We do not generally see looked for in the unequal heating of its them, but when the lower current is <ifferent strata by the sun, and in the so much saturated with moisture that unequal loss of heat through radiation clouds are formed in it, we do see a

From these considerations system of wave-like parallel clouds, he inferred the existence of an ascend- which often extend over wide parts of ing current in the equatorial belt, an the sky. To calculate the sizes of the upper warm current, and a cold polar waves in different cases is extremely current. As to the eastward and west- difficult, if not impossible ; but by taking ward directions of these currents, he some simpler cases Helmholtz and Obermade the very just remark that the beck showed that when the waves on energy of rotation of the whole atmo- the sea attain lengths of from sixteen sphere must remain constant and un- to thirty-three feet, the air waves must changed, even though masses of air attain lengths of from ten to twenty move from one latitude to another. miles, and a proportional depth. Such The velocity of rotation of the atmo- waves would make the wind blow on sphere in tropical latitudes must there- the earth's surface in rhythmical gushes, fore lag behind the rotation of the earth, which we all know, and they also would and it must outstrip it in higher lati- more thoroughly mix together the sutudes, mathematical calculation proving perposed strata, dissipating the energy that the thirty-fifth parallel is, in both stored in strong currents. These views hemispheres, the line of division be- are so correct that they undoubtedly tween the two. The general system of will throw some new light, as they air circulation deduced from these prin- already begin to do, upon the theory of ciples is very similar in its results to cyclones.1 the system of Ferrel ; but the interest At the same time, Bezold is now enand importance of Siemens' views lie deavoring to reconstruct meteorology elsewhere. His memoirs were an ap- from the point of view of thermodypeal and an attempt to apply the princi- namics ; 2 and the well-known Austriau ples of thermodynamics to the aerial meteorologist J. Hann, whose work is currents, and they have opened the exciting just now a great deal of interway for a series of important researches, est, has openly broken with the old which, however, are not yet sufficiently theory as regards the origin of cyclones advanced to be discussed in these pages. and anti-cyclones.8 From observations

And, finally, a third new point of made for several years in succession on view has been introduced into the same the top of the Sonnblick- a peak twelve discussions by Helmholtz. Sitting one

1 H. Helmholtz, “Zur Theorie von Wind und (lay by the seaside, and observing how

Wetter,” and “Die Energie der Wogen und des wind blows on the surface of the sea by Windes,” in the “Sitzungsberichte” of the Berlin sudden gushes, how it originates waves, Academy, 1889, li. and 1890, ii. Oberbeck's calcuand how they grow when wind blows ations of the waves are given in the Meteorolo

gische Zeitung, 1890, p. 81. with an increasing force, Helmholtz 2 “ Zur Thermodynamik der Atmosphäre," in came to consider what would bappen "Sitzungsberichte” of the Berlin Academy of with two air currents blowing one

Sciences, 1888, p. 485; same year, p. 1189 ; 1890, p.

355; and 1892, p. 279. above the other in different directions.

vom November, A system of air waves, le concluded, 1889,” in “ Denkschrift der Wiener Akademie der

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Wissenschaften, 1890, Bd. lvii., p. 401. der Wissenschaften,” March, 1886, p. 261 ; “Ueber kungen über die Temperatur der Cyclonen und das allgemeine Windsystem der Erde,” in same Anticyclonen," in " Meteorologische Zeitschrift," publication, 1890, ii., p. 629.

1890, p. 328.

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