or May-because they believe that it kills | pitious to the success of the experiment. young buds with its icy glare. They do The requisite arrangements being made, our satellite great injustice. When the the Professor turned the cone of the insky is clear, the earth parts readily with strument to the moon, as much as to say: the heat it has acquired during the day, "Now, madam, be pleased to tell us and the sprouting vegetables consequently frankly whether you have a spark of fire suffer from cold: but when a thick cur- in your beams, or whether you are the tain of cloud is drawn over the firmament, cold chilling creature some persons choose that heat is retained or reverberated, and to assert. If you are not an icicle, oblige the young plants are kept comfortable me by moving this slender magnetic neeuntil the sun returns. As the moon, how- dle, and then a long litigated problem will ever, is necessarily invisible when the be solved." The observer looked anxheavens are overcast, and as her appear- iously at the little metallic tongue which ances synchronize with the sufferings of was to convey her reply. It yielded! the nurserymen, these good people angri- slightly, very slightly, it is true; but still ly throw the entire blame upon her, and sensibly. To make sure of the fact, he justify their wrath by declaring that her repeated the readings about two hundred rays are full of frost. times that evening, varying the direction of the cone at intervals. In the course of an hour and a half (says he): "I was extremely pleased to find that the mean of the numbers indicated an undoubted heat effect of about a third of a degree." Rejecting, however, the idea of any chilling qualities in our little luminary, it has been supposed that the action of the atmosphere will explain the calorific poverty of her beams. If the sun's shafts suffer such a per centage of loss in their transmission through the air, what will be the case with the borrowed radiance of the moon? Will not the upper portions of the atmosphere suck out the heat from her rays, and consume it, as Sir John Herschel supposes, in dissolving the vapors upon which they impinge? It was obvious, therefore, that if the lunar beams could be tested before they dip into the denser part of the aerial ocean, the problem of their temperature might be investigated with more decisive results. And here was a philosophical Endymion, quartered on a mountain peak, with nearly 9000 feet of atmosphere beneath him, and the prevailing clouds of the region almost half that distance below his feet. What could be more favorable for a thermometric interview with the goddess? Teneriffe is higher than Latmos, and Mrs. Smyth was at her husband's elbow to protect him from all scandalous remark. Certainly a third of a degree, as degrees go on the thermo-multiplier, is a mere bagatelle. The simple warmth of the observer's naked hand at the distance of three feet sufficed to drive the magnetic needle through an arc of seven degrees. In order, however, to obtain a comparative estimate of the force of the lunar caloric, Professor Smyth placed a candle upon a stool fifteen feet from the pile, and found that it emitted a quantity of heat equal to three times that which had been produced by the moon. Assuming, then, that his experiments were tolerably uniform in their results, we must conclude that the earth owes little to its satellite in the article of warmth. For here, shining brilliantly as she did, without a cloud or a mist to lessen her splendor, the whole miserable pittance of caloric she afforded was not equal to that of a candle stationed at the distance of a few feet. And if so feeble in her issues of heat, is it likely, on the other hand, that she can radiate any mischievous influences from her orb? Who will now believe that she can kill sprouting cabbages, putrefy flesh, exaspe rate lunatic brains, or execute any other of the wicked pranks for which she has so frequently been blamed ? On the 15th August the question was formally asked. It was put by means of a delicate thermo-electric pile. Every precaution was taken to guard against the inroads of foreign caloric. No lights or fires were permitted to exist within a considerable distance of the apparatus. The Of course the astronomer availed himobserver himself was swathed in flannel to self of his propinquity to the moon-for prevent the conveyance of heat from his the removal of a mile and a half of feculent own body. The air was perfectly tran- atmosphere was a virtual approximation quil, and, except that the moon was low to that luminary-to peer into her wonin declination, every thing appeared pro-derful pits. Are they volcanic construc Very interesting and important also were Professor Smyth's observations on Jupiter. That the bands which cross the disc of this planet are regions of cloud has long been assumed; but now, surveyed under high telescopic powers from the clear altitudes of Teneriffe, their true character was elicited beyond all question. The bright parts are obviously vaporous masses, for their forms are as specific as those of our globe. There they weresailing along under the influence of currents created by the rotation of the orb on its axis, just as our own sublunary cumuli are driven by our own sublunary tions, or are they not? Many geologists | for the occasion, or manufacturing a mondoubt their fiery parentage, or at least ster like that which Butler describes in question their family resemblance to the his Elephant in the Moon. Etnas and Heclas of the earth. But after a few observations, and with such a fine sample of a terrestrial crater at his feet, the Professor soon satisfied himself on the point. In several of the hollow mountains of the moon it was impossible to overlook the gentle slope without, the sharp abrupt descent within, the large flat floor, and the peak springing from the center. These were precisely the features which the great basin of Teneriffe might have exhib. ited to a lunar astronomer, could he have probed it with a "Pattinson Equatorial," though certainly this rock is a protruded mass, where is the cavities in many of the moon's circular structures are depressed" trades." It was difficult to gaze at the below the level of the adjoining region. Here and there, too, the observer could detect something like a collection of stony lava streams; and when the Spaniards were allowed to examine these and other appearances in the moon, they compared them, without hesitation, to kindred peculiarities in their own private little volcano. Even the singular whiteness noticed by the Professor in the interior of the lunar craters was explained by the caldera of the Peak, where the steam and acid fumes issuing from numerous vents had blanched the rock, and given it the glistening look which it must doubtless have presented to a foreign telescope of competent caliber. But more was expected of the Professor than this. Some peasants came to him one day with a pleasing and romantic notion in their heads. They had heard strange things of the English astronomer and his prodigious tube. They had been informed that he could actually see into the moon. And if he could do this, what objects must inevitably meet his eye? Clearly, goats. Knowing little of other animals, these simple herdsmen imagined that their own staple quadruped must be as indispensable to the Lunarians as to themselves. Would the Professor allow them to look? It would be so pleasant to see the creatures skipping about in that distant world! Doubtless it was a source of great grief to the astronomer that he could not gratify their wishes. Many a wicked wag, we are afraid, would have had his fun out of these unsophisticated islanders by getting up a lunar "goat" equatorial parts of the planet without "acquiring the impression of looking at a windy sky: the whole zone of vapor seemed to be in motion; while from its ragged edge portions were torn off and were driving along, some of them rolling over and over, and others pulled out in length, and rearing up towards the forepart, like a sailing-boat scudding before a gale." The polar regions of Jupiter appeared to be quieter and less troubled; but this, as the author says, might be simply the effect of perspective. He came to the conclusion, also, that there was here, as there is on our earth, a "medial line of calm "a half-way belt of tranquillity-in the atmosphere, which does not exactly correspond with the equator. Should this be "borne out by future observations, it may be held to arise from the same causes which make the Southern Trades overbalance the Northern upon our earth, and throw the zone of so-called equatorial calm into north latitude, namely, the unequal distribution of land and sea surface in the two hemispheres. Such a result would be proving much, seeing that some theorists have been lately contending for Jupiter and all the outer planets being mere globes of water with at most a cinder nucleus." We commend this remark to the attention of that arch-assailant of the Jovian orb, the author of the Plurality of Worlds. From what slight circumstances may we not extract important conclusions! Those belts entitle us to assume that yon distant globe is furnished with clouds, winds, trade currents, land glided into a generalization, which further experience has fully confirmed. It may be stated thus: "The red streams again, are evidently much smaller in extent than the yellow, and have never run or spread very far. Their terminal markings are more like the wrinkles of a glacier than the waves of water; and, besides these longitudinal arrangement, in some transverse features, there are beginnings of a cases, as mentioned above, looking like the lateral moraines of an ice stream. In others, they give one the idea of nothing so much as the ruts of chariot-wheels of Grecian demigods, driven with celestial power through the bewildered plain of loose red stones. and water, unequal continents, and a rotary movement on its axis, precisely similar to the features of our own little earth. "The earliest lava streams are of a yellow Occupied in the investigation of these and other scientific questions, the Profes--and the last one blue-black. The yellower tint, the succeeding ones red-a rich Indian red sor proceeded, after a sojourn of more appear to have been the most abundant, as well than a month on Guajara, to enter the as most fluid, for they cover the largest spaces, great crater, and climb the Peak in its have flowed over nearly level tracts, and their center. The direct distance was only ridges imitate the forms of watery waves. In four miles, but four miles of volcanic trav- one of our photographs of the south-eastern eling are equal to a pretty long scramble corner of this broad crater, the confines of a through the ruins of a prostrate city. To rushing up the curving beach in surf-like waves, flood of yellow lava from the peak may be seen an ordinary observer, the descent into this as with the sea on the coasts below. huge caldron-a caldron with a rim more than twenty miles in circumference would have presented a scene of gigantic confusion. No order was apparent in its tumbled masses of rock and jostling streams of ancient lava; but the philosophic eye soon resolved it into shape, and mapped out its true character. What was that long ridge of blocks, heaped upon each other in the wildest fashion and at the most perilous angles for the passenger? It was a great wave of lava which had once broken on the beach of a fiery lake, or dashed against the cliffs of the crater. There was a time when it issued from the entrails of the mountain, glowing with the heat of those awful furnaces which can melt the stubbornest substances like wax; now it stands before you a huge petrified billow. Advancing along the floor of the basin, the travelers found themselves amongst rugged and intricate rocks, where the very guides were bewildered, and lost their way. It was not until much hallooing, and many tedious windings in and out amongst the stony masses, that the trail was recovered. They ceeded thus through a region of profound desolation, where red rocks, and inky lava streams, and yellow pumice dust seemed to make a fit flooring for an oven into which the sun shone with mountain fervor. In the evening they reached Alta Vista, an elevation of 10,700 feet, which is the Ultima Thule of all beasts of burden. It was from heights like these that the geography of the crater could be best studied, and the vision of its geological past most readily recalled. Hear what the Professor says of his survey from the station he had just quitted at Ġuajara : pro "Day after day we gazed at, sketched, and discussed these various outpourings which had flowed down from the central peak, deluging the plain of the great crater, and insensibly we iest of all: they have never moved, except "The black streams are decidedly the scantwhen the slope was very notable; and with them the longitudinal arrangement, which had just begun to appear in the red, predominates; all the black streams, being nothing but a series of long ridges of embankment. They have not the form of any fluid stream, watery, or viscous, but rather of a quantity of finely-comminuted solids, as sand; their sides, and even their ends, being sloped so uniformly at a constant angle, that they look here and there amazingly like embankments formed by railway navvies. "I do not propose here to enter into minutiæ of the absolute manner of movement of a lava stream, and the oft-discussed influences of viscosity and crystallization in modifying its manof shape, on the large scale, actually subsisting ner of flowing, but only to point out differences amongst different streams. These shapes, being undoubtedly an expression of the particular mechanical forces once exerted in each case, must be replete with instruction, if rightly interpreted. Their study constitutes, indeed, a sort of colossal or telescopic mineralogy, which assumed, in my eyes, quite an aspect of profesby which we can legitimately compare the sursional importance, as presenting the only means face of the moon with that of the earth. "The relative ages of streams alluded to in the enumeration already given, we ascertained by their position. The color was an accident, or at least was superficial; but the differences of form were something of a far greater importance, and when taken in conjunction with other features-also capable of accurate measurement, of the bed-indicated besides their age, the graas relative extent, quantity, and angular slope dation of heat in the different classes of streams, and showed, at least with this volcano, that a secular progress had accompanied its periodical movements.' Without entering into any details of the flitting from Guajara, and temporary establishment at Alta Vista, let us join the Professor and his party on their emerging from the Malpays-a region of very bad character, as the name sufficiently implies. It was then that the true cone of Teneriffe rose before them like a great tower, with its red and yellow flanks flashing in the rays of a brilliant sun. Clambering up the acclivity, the height being about 470 feet on the eastern side, they observed many holes and fissures in the rock, and in these a decided sensation of warmth was felt. Hotter and more numerous the cracks became as the party advanced, and soon a sulphurous odor was plainly perceived. Advancing eagerly, at last they stood on the brink of the crater which crowns the mountain. Is it the fearful abyss it has sometimes been represented? Let the Professor speak for himself, as he well knows how to do: "Fagh! on inhaling the first whiff, one was inclined to beat an instant retreat for a few steps; looking for the moment with infinite disgust on the whole mountain, as nothing more than the chimney, 12,200 feet high, of one of nature's chemical manufactories. This chimney, having been built at great expense, she was resolved to turn it to account. We curiously-foolish creatures, had been innocently creeping up the sides, and were now astonished to find, on peering over the mouth of the long stalk, that noisome fumes were ascending from it. "Again we mounted up to the brim, and soon getting toned down to breathing mephitic exhalations, found the chief feature of the craterinterior some 300 feet in diameter and 70 feet deep, to be its extreme whiteness; often white as snow, where not covered with sulphur. The breadth of rim was hardly sufficient to give standing room for two, so immediately, and in such a knife edge, did the slope of outside flank meet that of inside wall. On the portion of circumference where we collected, the ground was hot, moist, dissolving into white clay, and full of apparent rat-holes. Out of these holes, however, it was, that acidulated vapors were every moment breaking forth, and on the stones where they struck were producing a beautiful growth of needle-shaped crystals of sulphur, crossing and tangling with each other in the most brilliant confusion. "The north-eastern, northern, and northwestern, were the highest, whitest, and hottest parts of the crater walls. Towards the west and south they dipped considerably, and verged to an ordinary stone-color inside; outside they were red and brown all the way round the cir- "Only in the neighborhood of the walls is there much annoyance from puffing steam and vapor, while neither there nor any where else is more than a thin coating of sulphur, often bedewed with sulphuric acid, to be found. If all the sulphur on the peak were to be gathered together, by scraping it off the stones, a long an i tedious operation in itself, there would hardly be two barrowsful obtained; and speculators therefore, in England, need not incur the expense of sending up here, to the height of 12,200 feet, for so scanty a supply." not yet totally superannuated. We can It appears, therefore, that Teneriffe is It still does a little business, though on a not treat it exactly as a retired volcano. scale so trivial that were it not for a few puffs of steam and a slender sublimation of sulphur, we might fancy it had withdrawn into private life. It seems to discharge a small quantity of heated vapor, the burning mountains of the globe. But just by way of keeping up its rank amongst it is some time ago since it indulged in any of the professional paroxysms of a volcaco. We can not say of it, as Virgil says of Etna-and, indeed, it would be a pity if we could: "Interdumque atram prorumpit ad æthera nu- Turbine fumantem piceo et candente favilla. bit. Interdum scopulos, avulsaque viscera montis Erigit eructans, liquefactaque saxa sub auras Cum gemitu glomerat, fundoque exæstuat imo." It is half a century ago, indeed, since any decisive steps were taken by the mountain, and these were not equal to its proceedings when the penultimate eruption occurred, in the year 1704-5. At the last-named period-distinguished as the "earthquake year "-a great river of lava broke from one of the parasitic craters, and dashed into the town of Garichico, whose bay it filled up completely, so that buildings were soon erected where the waves had formerly played. In January, after a succession of shocks and a terrible darkness in the heavens, torrents of fire poured from various vents, and set the country in a blaze wherever they wandered. One of these rushed towards the little town of Guimar, already shattered by the heavings of the soil, and dividing into two branches just before it reached the place, the inhabitants found themselves hemmed in by burning streams on either hand, with the sea raging before them, and earthquakes rolling beneath their feet. no more vicious propensities, and that the Canarians will never have the misery of seeing it in active practice again. It is a serious question for the globe, however, whether volcanic power is decaying at large, and whether the great forces of elevation which have so often counteracted the disintegrating agencies of wind and water-agencies always laboring to fill up our seas, and reduce the world to a monotonous level-are growing feeble and emaciated with age. Returning to the station at Alta Vista, the astronomer continued his observations for a few days, but the fine weather soon began to show symptoms of bankruptcy. The barometer fell fast, and the hygrometer spoke strongly of the increased humidity of the air. Mists ventured to gather round the mountain-top, and, as the Spaniards say, rain may be expected cuando el pico tiene puesto su sombrerillo when the peak has mounted his little sombrero. Clouds, too, came up in great force from the south-west, and at a lower level, to fight those of the north-eastnot hopelessly now, as they had done on one occasion some weeks before, when a grand aërial engagement ensued, which the Professor has described in a fine animated bulletin. But now the battle took place on equal terms; the trades were defeated; and as these were the champions of the Canarian summer, whilst the low south-westers were the representatives of autumnal rain, it soon became manifest that the astronomical season was at an end. Teneriffe in clouds was as unfit for an observatory as the bottom of a coal-pit; and therefore, on the 19th September, the Professor descended from his eyrie, and became once more a dweller on the plains. Still, though the volcano has sunk into comparative quiescence for the present, it is a question with philosophers whether it is simply in a state of suspended animation, or is dying from pure decrepitude. Collating his own observations with those of former travelers, "Humboldt concluded a cooling of this crater; Bertholet, in 1830, in a similar manner, concludes a heating, and speculates in a lively French manner on what a catastrophic destruction of men will ensue when this hoary old volcano resumes its pristine energy. As far as we could make out, the ground is heated by the steam which permeates it, and which indicated in the strongest But we must not draw too freely upon holes only 150°, whilst the boiling point the contents of this pleasing work. Though of water, which we ascertained by careful not a large, it is a magnificent volume. experiment in a deep cleft, on the west-The stereographs are a novelty, of which ern side of the crater, is 191° 08. There would seem, therefore, to be no high pressure' at work, nor, indeed, any sensible difference in the effects on the whole since the day of Captain Glas, nearly a century ago." In fact, from the relative scantiness of the more recent streams of lava, and their apparently inferior fluidity, Professor Smyth assumes that the Peak has been dying out for years, and is now in a state of hopeless decline. Let us hope, therefore, that Teneriffe will exhibit VOL. XLIV.-NO. II. both author and publisher may be proud. It was a happy thought to introduce these dual pictures into a printed book, and make them available by means of a stereoscope which may be carried in the pocket, or sent by post as easily as an or dinary valentine. To Mr. Lovell Reeve, whose scientific attainments qualify him so worthily for the publication of treatises like these, the public owes many thanks for his beautiful extension of the photographic art. Should it become common, 16 |