From Nature.

THE UPPER CURRENTS OF THE

ATMOSPHERE.

1000 inch. From the greatly steeper barometric gradients thus formed for upper currents during the cold months of the year from equatorial to polar regions, these currents attain their maximum strength in winter and converge upon those regions of the earth where the mean temperature is lowest.

barometric gradients for the upper currents of the atmosphere will be formed during the coldest months of the year. ALL winds are caused directly by dif- At Bogota, 8,727 feet in height, where the ferences of atmospheric pressure, just in temperature is nearly uniform throughout the same way that the flow of rivers is the year, the mean pressure for January caused by differences of level; the mo- and July are 22.048 and 22:058 inches. tion of the air and that of the water being On the other hand, at Mount Washington, equally referable to gravitation. The 6,285 feet high, where the January and wind blows from a region of higher towards July mean temperatures are 6o4 and 48°.2, a region of lower pressure, or from where the mean pressures for the same months there is a surplus to where there is a are 23.392 and 23'875 inches. Similarly deficiency of air. Every isobaric map, at Pike's Peak, 14,151 feet high, the mean showing the distribution of the mass of temperatures are 3°.1, and 39°7, and the the atmosphere over any portion of the mean pressures 17:493 and 18.069 inches; earth's surface, indicates a disturbance and since the sea-level pressures in the more or less considerable of atmospheric region of Pike's Peak are nearly 0.500 equilibrium, together with general move-inch higher in January than in July, it folments of the atmosphere from regions of lows that the lowering of the pressure on high pressure towards and in upon low- the top of Pike's Peak due to the lower pressure areas. All observation shows, temperature of January is upwards: of further, that the prevailing winds of any region at any season are merely the expression of the atmospheric movements which result from the disturbance of the equilibrium of the atmosphere shown by the isobaric maps as prevailing at that season and over that region. All observation shows, in a manner equally clear and uniform, that the wind does not blow directly from the region of high towards that of low pressure, but that, in the northern hemisphere, the region of lowest pressure is to the left hand of the direction towards which the wind blows, and in the southern hemisphere to the right of it. This direction of the wind in respect of the distribution of the pressure is known as Buys Ballot's law of the winds, according to which the angle formed by a line drawn to the centre of lowest pressure from the observer's position, and a line drawn in the direction of the wind is not a right angle, but an angle of from 60° to So°. This law absolutely holds good for all heights up to the greatest height in the atmosphere at which there are a sufficient number of stations for drawing the isobarics for that height; and the proof from the whole field of observation is so uni form and complete that it cannot admit of any reasonable doubt that the same law holds good for all heights of the atmosphere.

In low latitudes, at great elevations, atmospheric pressure is greater than it is in higher latitudes at the same height, for the obvious reason that owing to the lower temperature of higher latitudes the air is more condensed in the lower strata, thus leaving a less pressure of air at great heights. It follows that the steepest

As is now well known, atmospheric pressure in summer is lowest in the central regions of the continents of Asia, Africa, and America; and highest in the Atlantic between Africa and the United States, and in the Pacific between the United States and Japan, the absolutely lowest being in Asia, where temperature is relatively highest with respect to the regions immediately surrounding, and absolutely lowest in the Atlantic, which is most completely surrounded with highly heated continental lands. Again, in winter the lowest atmospheric pressures are found in the north of the Atlantic and Pacific Oceans, where temperature is rel. atively highest, latitude for latitude; and the highest pressures towards the centres of the continents, some distance to southward of the regions where at this season abnormally low temperatures are lowest.

The causes which bring about an unequal distribution of the mass of the atmosphere are the temperature and the moisture considered with respect to the geographical distribution of land and water. Owing to the different relations of land and water to temperature the summer temperature of continents much exceeds that of the ocean in the same latitudes. and hence results the abnormally high temperature of the interior of Asia, Africa, America, and Australia during their

thereafter spreads itself horizontally as upper currents towards those regions which offer the least resistance to it. The overflow of the upper currents is thus in the direction of those regions where pressure at the time is least, and this again we have seen to be towards and over that region or those regions the air of which in the lower strata of the atmosphere is colder and dryer than that of surrounding regions.

respective summers, in consequence of the surrounding air, ceases to ascend, and which the air becoming specifically lighter ascends in enormous columns thousands of miles in diameter. Winds from the ocean set in all round to take the place of the air thus removed, raising the rainfall to the annual maximum, and still further diminishing the atmospheric pressure. On the other hand, since in winter the temperature of the continents and their atmosphere falls abnormally low, the air becomes more condensed in the lower strata, and pressure is thereby diminished in the upper regions over the continents. Upper currents set in all round upon the continents, and thus the sea-level pressures become still further increased. Hence the absolutely highest mean pressure occurring anywhere on the globe at any season, about 30 500 inches, occurs in Africa in the depth of winter.

Now observation conclusively proves that from the region of high pressure in the interior of Asia in winter, from the region of high pressure in the Atlantic in summer, and from all other regions of high pressure, the winds blow outwards in all directions; and that towards the region of low pressure in Asia in summer, towards the region of low pressure in the north of the Atlantic in winter, and towards all other regions of low pressure, whenever and wherever they occur, the winds blow in an in-moving spiral course. Since enormous masses of air are in this way poured into the region where pressure is low without increasing that pressure, and enormous masses of air flow out of the region where pressure is high without diminishing that pressure, it is simply a necessary inference to con. clude that the masses of air poured all round into the region of low normal pressure do not accumulate over that region, but must somehow escape away into other regions; and that the masses of air which flow outwards on all sides from the region of high normal pressure must have their places taken by fresh accessions of air poured in from above. Keeping in view the law of the barometric gradient as applicable to all heights of the atmosphere, it is evident that the ascending current from a low-pressure area, the air composing which is relatively warm and moist, will continue its ascent till a height is reached at which the pressure of the air of the current equals or just falls short of the pressure over the surrounding regions at that high level. On reaching this height, the air, being no longer buoyed up by a greater specific levity than that of

The broad conclusion is this: the winds on the surface of the globe are indicated by the isobaric lines showing the distribution of the mass of the earth's atmosphere near the surface, the direction of the wind being from regions where pressure is high towards regions where pressure is low, in accordance with Buys Ballot's law. On the other hand, the low-pressure regions, such as the belt of calms in equatorial regions, the interior of Asia in summer, and the north of the Atlantic and Pacific in winter, with their ascending currents, and relatively higher pressure at great heights as compared with surrounding regions, point out the sources or fountains whence the upper currents flow. From these sources the upper currents spread themselves and flow towards and over those parts of the earth where pressure is relatively low. These directions are, speaking generally, from equatorial to polar regions; but more particularly towards and over those more restricted regions where in the lower strata of the atmosphere the air is colder and dryer than in neighboring regions, such as the Atlantic between the United States and Africa in summer, and central Asia in winter.

This view of the general movements of the upper currents of the atmosphere is in accordance with the observations which have been made in different parts of the globe on the motions of the cirrus cloud, and with observations of the directions in which ashes from volcanoes have been carried by these upper currents. In further corroboration of the same views, reference may be made to the researches made in recent years, particularly by Prof. Hildebrandsson and Clement Ley, into the upper currents of the atmosphere, based on observations of the movements of the cirrus cloud in their relation to the cyclones and anticyclones of north-western Europe.

An important bearing of cyclonic and anticyclonic areas on the distribution of temperature may be here referred to.

The temperature is abnormally raised on the east side of cyclonic areas and abnormally depressed on their west sides; but, on the other hand, temperature is ab. normally raised on the west sides of anticyclonic areas, and depressed on their east sides the directions being reversed in the southern hemisphere. Since the temperature is lower in the rear than in the front of a cyclone, it follows that, relatively to the sea-level pressures, pressure will be lower in the upper regions in the rear of a cyclone than in front of it, a result which the Ben Nevis observations strongly confirm. Hence relatively warmer and moister upper currents will flow backward over the colder and dryer air immediately in the rear of the centres of cyclones; and upper currents also presenting contrasts of temperature and vapor will overlap the outskirts of anticyclones. These considerations suggest how very diverse interpretations of the movements of the cirrus cloud in their relation to cyclones and anticyclones have originated, and may also indicate lines of research into some of the more striking optical scenic displays of the atmosphere.

See "Reviews of Weather Maps of the United States," Nature, vols. xxi., xxii., and xxiii.

From The Spectator.
THE TENNYSON PEERAGE.

pen to be one distinguished on the political side or not, adds to the scenic impressiveness of the House of Lords, and to the respect felt by the nation for its collective influence. We are far from denying that there may be something to be said for that view. It is certain that a good deal of just national pride in the possession of such a poet as Mr. Tennyson is felt, and also that Mr. Tennyson has a keen feeling for the statelier aspects of constitutional liberty, and has given expression to that class of emotions in some of the finest verse of the last half-century. That he is one of our great national dig. nities, we should be the last to question. And yet we do question very greatly whether his accession to the peerage would add to the weight of the peerage, and, still more, whether it would not to some extent detract from the dignity which at present unquestionably attaches to his own name.

The truth is, that the dignity attaching to the name of a great poet, like the dig nity attaching to the name of a great saint, has something spiritual about it, which does not seem to accord well with the kind of respect which the conferring of a peerage is capable of expressing. We do not in the least mean to assert that there is anything necessarily inconsistent between poetry and a title. There are several poets, including one great poet, who have been peers, and who have not been less esteemed as poets for their peerage. Lord Houghton's poetry and Lord LytIt seems tolerably clear that, whatever ton's novels did not fall in public estimamay be the actual result, the poet-laureate tion because their authors accepted a seat has been assured of the wish of the crown in the House of Lords, but then both Lord to raise him to the dignity of a peerage. Houghton and Lord Lytton were made We conclude, therefore, that the prime peers chiefly on the strength of their politminister, on whom must devolve the duty ical achievements and their social influ of making such a recommendation as this ence. Mr. Tennyson, if he is to be a to the queen, entertains the view that the peer, will become a peer solely because he House of Lords should be a sort of reser has fired the imagination of the English voir of all the dignities of the nation, even people, and that is not the kind of distincwithout relation to any special fitness for tion which seems to us to be at all natuthe particular functions-the political rally expressed by ranking him amongst functions which are expected of its the barons or viscounts of England. If members. The late Mr. Bagehot used Charles Lamb had been a man of ever so always to speak of the throne and the good a fortune, no one would have House of Lords as the ornamental and thought of making a peer of him on the dignified parts of the Constitution, strength of his wit, his humor, and the those parts of the Constitution which delightful vagaries of his lively fancy. most impress the imagination of the peo- There is something incommensurable be ple, and give them a certain pride in the tween the literary qualities of such a man national unity and life in virtue of the ex- as " Elia" and a peerage; and the same ternal magnificence with which it moves. remark applies, though probably in a less Perhaps Mr. Gladstone holds that the degree, to Tennyson himself. That the addition of any really great national figure author of "In Memoriam" or "Break, to the House of Lords, whether it hap-break, break," should be made a peer

because he possesses the great poetic gifts needful to produce those marvellous productions, seems to us almost as incongruous as it would have been to confer a peerage on Charles Wesley for writing some of the most beautiful hymns in the English language, on Wordsworth for his "Ode on the Intimations of Immortality," on Keats for his "Hyperion," and on Shelley for his " Skylark" and his "Adonais." There was dignity in all these poets, and great dignity in Words worth, but not the kind of dignity that you could aptly express by summoning him to take his seat beside the Earl of Lonsdale on the benches of the House of Lords. So far as we know, this is the first case in which poetry has been thought the proper title deed for a peerage. Doubtless, a baronetcy was given to Sir Walter Scott in some degree, we suppose, for his literary achievements; but even that was not given him till he had become a man of great social influence in Scotland, -a lawyer and sheriff of no small repute,

only to sit uneasily on a great poet, but to fit awkwardly into the entourage of the House of Lords. The king of Prussia might almost as well have made Kant a Graf for writing the "Kritik of Pure Reason," as the queen confer a peerage on Mr. Tennyson for singing his elegy on the death of Arthur Hallam, and writing the noble series of poems called the "Idyls of the King." Whatever distinction the poet-laureate may confer on the House of Peers, we fear it must be an incongruous distinction, like a patch of rich Oriental workmanship let into the centre of a solid Brussels carpet, or the illumination of a medieval missal embodied in the pages of Caldecott. That Tennyson would be a great ornament to the House of Lords, we are far from denying. But he will be an incongruous ornament, such an ornament as a wreath of roses round the brow of the governor of the Bank of England, or a spiritual smile on the countenance of a London lord mayor.

From Nature.

THE JAVA DISASTER. THE following letter from the Liverpool Daily Post, received from Capt. W. J. Watson, of the British ship" Charles Bal," contains a graphic and interesting account of the recent terrible volcanic outburst in Sunda Straits. Capt. W. J. Watson was himself an eye-witness of what he describes. His vessel was actu ally within the Straits, and not far from Krakatoa when that island had become an active volcano:

46

and till it was known that he attached at least as much importance to founding a family and getting together a landed estate, as he did to the literary achievements by which he had been enabled to compass these ends. Scott was already a magnate before he received the baronetcy, it was because he was a magnate that the offer of the baronetcy seemed appropriate, not because he was a poet and a novelist. Our own view is that a peerage is an appropriate distinction only for those who, in some degree, already wield and deserve political influence, and not as a mark of popular reverence for any qualiities, whatever they may be, which justly deserve reverence. Keble deserved rev- August 22, 15° 30′ S., 105° E. — About erence for the qualities which enabled him 7 P.M. the sea suddenly assumed a milkyto write "The Christian Year," but no white appearance, beginning to the east one would have felt it a natural and fitting of us, but soon spreading all round, and way of expressing that reverence to have lasting till 8 P.M. There were some clouds raised him to the House of Lords. No (cumulus) in the sky, but many stars doubt, there are certain qualities of poetic shone, and in the east to north-east a imagination, the statelier qualities, we strong, white haze or silvery glare. This mean, which seem less out of keeping occurred again between 9 and 10 P.M., the with a coronet than devotional poetry like clouds also appearing to be edged with a Keble's, and we are far from denying that pinkish-colored light, the whole sky also Mr. Tennyson displays them. Still, make seeming to have extra light in it, similar what you can of the magnificence of his to when the aurora is showing faintly. verse, and it is not a kind of magnificence On the 24th, in 9° 30′ S., 105° E., we had which seems to be in sufficient harmony a repetition of the above. On the night with worldly distinction, to admit of expressing your respect for it by conferring a great worldly distinction. Make out what case we may, a peerage conferred for poetic achievements alone will remain a "fancy peerage," which will seem not

of the 25th, standing in for Java Head, the land was covered with thick, dark clouds and heavy lightning. On the 26th, about 9 A.M., passed Prince's Island, wind south-west, and some heavy rain; at noon, wind west-south-west, weather fine, the

island of Krakatoa to the north-east of very unsteady, between south south-west us, but only a small portion of the north- and west-south-west, the same impenetra east point, close to the water, showing; ble darkness continuing, the roaring of rest of the island covered with a dense Krakatoa less continuous, but more exblack cloud. At 2.30 P.M., noticed some plosive in sound, the sky one second inagitation about the Point of Krakatoa; tense blackness and the next a blaze of clouds or something being propelled from fire, mastheads and yardarms studded the north-east point with great velocity. with corposants and a peculiar pinky flame At 3 30 we heard above us and about the coming from clouds which seemed to island a strange sound as of a mighty, touch the mastheads and yardarms. At crackling fire, or the discharge of heavy 6 A.M., being able to make out the Java artillery at second intervals of time. At shore, set sail, passing Fourth Point light4.15 P.M., Krakatoa north half east, ten house at 8; hoisted our signal letters, but miles distant, observed a repetition of got no answer. Passed Anjer at 8.30, that noted at 2.30, only much more furi- name still hoisted, close enough in to ous and alarming, the matter, whatever it make out the houses, but could see no was, being propelled with amazing veloc- movement of any kind; in fact, through ity to the north-east. To us it looked like the whole Straits we have not seen a sinblinding rain, and had the appearance of gle moving thing of any kind on sea or a furious squall of ashen hue. At once land. At 10.15 A.M., passed the Button shortened sail to topsails and foresail. Island one-half to three-quarters of a mile At five the roaring noise continued and off; sea like glass round it, weather much increased; wind moderate from south-finer-looking, and no ash or cinders fallsouth-west; darkness spread over the sky, and a hail of pumice-stone fell on us, many pieces being of considerable size and quite warm. Had to cover up the skylights to save the glass, while feet and head had to be protected with boots and southwesters. About six o'clock the fall of larger stones ceased, but there continued a steady fall of a smaller kind, most blinding to the eyes, and covering the decks to three or four inches very speedily, while an intense blackness covered the sky and land and sea. Sailed on our course until we got what we thought was a sight of Fourth Point light; then brought ship to the wind, south-west, as we could not see any distance, and we know not what might be in the Straits, the night being a fearful one. The blinding fall of sand and stones, the intense blackness above and around us, broken only by the incessant glare of varied kinds of lightning and the continued explosive roars of Krakatoa, made our situation a truly awful one. At II P.M., having stood off from the Java shore, wind strong from the south-west, the island, west-northwest, eleven miles distant, became more visible, chains of fire appearing to ascend and descend between the sky and it, while on the south-west end there seemed to be a continued roll of balls of white fire; the wind, though strong, was hot and choking, sulphureous, with a smell as of burning cinders, some of the pieces falling on us being like iron cinders, and the lead from a bottom of thirty fathoms came up quite warm. From midnight to 4 A.M. (27th) wind strong, but

ing; wind at south-east, light. At 11.15 there was a fearful explosion in the direction of Krakatoa, now over thirty miles distant. We saw a wave rush right on to the Button Island, apparently sweeping right over the south part, and rising half way up the north and east sides. This we saw repeated twice, but the helmsman says he saw it once before we looked. The same wave seemed also to run right on to the Java shore. At the same time the sky rapidly covered in; the wind came strong from south-west by south; by 11.30 we were inclosed in a darkness that might almost be felt, and at the same time commenced a downpour of mud, sand, and I know not what; ship going northeast by north, seven knots per hour under three lower topsails; put out the sidelights, placed two men on the look-out forward, while mate and second mate looked out on either quarter, and one man employed washing the mud off binnacle glass. We had seen two vessels to the north and north-west of us before the sky closed in, adding much to the anxiety of our position. At noon the darkness was so intense that we had to grope our way about the decks, and although speaking to each other on the poop, yet could not see each other. This horrible state and downpour of mud, etc., continued until 1.30, the roarings of the volcano and lightnings being something fearful. By 2 P M. we could see some of the yards aloft, and the fall of mud ceased. By 5 P.M. the horizon showed out in the north and northeast, and we saw West Island bearing east and north, just visible. Up to mid.