Page images

beck, on the east, above Windermere. Its quaint old cottages, in their yew-shaded courtyards, are without parallel elsewhere. Still the beck flows down to Windermere ; still, I hope, it is alive with trout. But does the inn of the Mortal Man still offer hospitality to the wayfarer-mutton-ham and oatmeal-cake and home-brewed ale ? Many a time did Coleridge, I feel certain, take his ease at that inn. The lines which were written on its signboard (I hope time has not effaced them) might have come from the humorous pen that produced the Devil's Walk:

"O mortal man, who livest by bread,
Why is thy nose so very red ?
O silly wight, with cheeks so pale,

It comes by drinking Troutbeck ale.' People seldom visit Lakeland in winter; but they should, to see Helvellyn and Skiddaw shrouded by snow, to see the waterfalls, swollen to torrents, struggling against the frost which solidifies the mist of their pools, and snatches from the descending stream icicles like colossal stalactites. That battle between the falling force and the restraining frost is worth travel to see; and the fantastic forms into which the water is tortured as it grows into crystals are quite beyond imagination or description.

After all, Dreamland, and not Lakeland, was Coleridge's true country. Well did he deserve those additional stanzas which Wordsworth wrote concerning him in the margin of the Castle of Indolence :

• A noticeable man with large gray eyes,
And a pale face that seemed undoubtedly
As if a blooming face it ought to be ;
Heavy his low-hung lip did oft appear
Deprest by weight of musing Phantasy;

Profound his forehead was, though not severe.' In that somnolent realm, delightfully pictured by Thomson, that land of dreams that wave before the half-shut eye,' Coleridge has a place of his own. Whoever has followed Christabel into the moonlit woodland, or the ancient mariner across the solitary sea where he killed the albatross, or has seen that stately pleasure-dome which Kubla Khan decreed in Xanadu,

• Where Alph, the sacred river, ran,
Through caverns measureless to man,

Down to a sunless sea,' will recognise in Coleridge the most divine of dreamers. Yes, though I have traced him in terrene regions, which he has royally made his own, yet do I repeat what I said, that Dreamland was Coleridge's country.



By scientific ballooning' I do not mean the application of so-called scientific and mechanical notions to the management, the propulsion, or the guidance of aërial machines ; that is a humiliating subjectone of grand intentions and ludicrous realisations. My title refers to the use of balloons for the ostensible purpose of advancing science, by carrying barometer and thermometer readers up into the higher airs, to ascertain how their instruments behave there, in the hope of furthering our small acquaintance with the constitution and commotions, the eddies and upper currents, of the atmospheric ocean at the bottom of which we dwell.

Ever since Montgolfiers took the air philosophy has been subject to spasmodic fits of sky-soaring. The habit of regarding every fresh thing as new has led many to suppose that balloon meteoroscopy is a novelty pertaining exclusively to the present decade ; but it is no such thing. The earliest ascent of any unfabulous aërial machine dates from the year 1783 ; and in a score of years, as soon as travelling became safer and the balloon ceased in some measure to be the sole right of showmen, ascents were made for scientific purposes alone. To rest the palm upon the proper crown, the honour of inaugurating this branch of research must be accorded to the Academy of St. Petersburg. There was a sort of toy experiment made in 1784, it is true, by Boulton, Watt's partner, but it is not worth calling scientific; it merely consisted in letting up a balloon with a slow-match attached to it, so as to explode the gas at a great elevation; the idea being to try if anything like thunder would be reproduced by reverberation of the explosion. Nothing came of it, however ; the people shouted so lustily that no cloud-born sound was heard at all.

During the first years of this century we find the savans lamenting that such a potent instrument as the balloon should have been abandoned to the use of those who pandered to the amusement of frivolous sightseers. It was a pity, the grounds of which must be removed, or science would be the loser by its apathy. So that ancient Academy of Sciences aforesaid voted the means for an ascent uniquely devoted to scientific progress. The programme was simple: the points aimed at were, to ascertain the physical conditions of the atmosphere; in fuller words, its pressure, temperature, dampness, and constituent proportions at different elevations. Most important was the determination of the law of decrease of density or weight of the air as the height increased. All that was then known upon this and the other points just mentioned depended upon observations made upon mountain - sides; and these were obviously vitiated by local influences, by terrestrial attractions exerted upon the superposed air, and by the presence of organic bodies, vegetable or animal. To catch the high air in its native purity, it must be soared into, and the balloon was the tool for the work.

The Coxwell of that period was one named Robertson, a native of Liége, a versatile genius; first a divine, then a professor of physics, then a phantasmagoriast, lastly an aëronaut. He built a small balloon thirty feet diameter, and generated hydrogen enough to fill it by decomposing water; he furnished the car for scientific observations with barometer, thermometer, timepiece, telescopes, birds, pigeons, phials to catch air in, and all necessaries and accessories. The Academy found the money, and appointed one of its members, M. Sacharoff, a chemist, to make the ascent with M. Robertson. It was on the 30th of June 1804 that this the first of scientific aërial voyages was made; the start was from the Jardin des Cadets in St. Petersburg, at seven o'clock in the evening. We need not follow the log of the journey; of late we have had relations of this sort almost ad nauseam. Suffice it to say, that the observers read their barometer and thermometer now and then, not apparently with much system, threw their pigeons, bottled the air at various heights up to about five thousand feet-their maximum altitude—ate their supper, determined to make the night of it, and joined hands to bind their intention, but afterwards thought better of it and came down, after a run of sixty versts that occupied about three hours. Two facts were noted that deserve separate mention. One was, that the needle of a compass inclined itself from the horizontal about ten degrees. An inclining or dipping' needle, as it is called, was taken up, but it was deranged, so that this singular vagary, important to magnetic science, could not be fairly examined. The other fact was, that when the aëronauts shouted through a speaking-trumpet, the sonorous percussions of the air produced a slight undulation of the balloon. Here was shadowed the power of man to rend the air by artificial thunders, to brew storms by repeated discharges of heavy cannon or any other great noises.

Science did not gain much from this ascent, directly; but the ball was set a-rolling, and very soon it was taken up by more illustrious players. In less than two months Biot and Gay-Lussac were up in a balloon. Their intentions bore chiefly on magnetic observations. Robertson, in the above voyage and in an earlier one, had suspected that the magnetic force which directs the compass-needle upon the earth's surface becomes enfeebled when the needle is carried high into the air. Saussure thought the same thing from his mountain experience. It was an important point to prove, because much of the theory of terrestrial magnetism depended upon it. To determine the relative intensity of the earth's magnetic power in different situations, a delicately suspended needle is set in vibration; the greater the terrestrial force, the sooner will it be pulled from its diverted to its normal position, and so the quicker will be its period of oscillation; conversely, the less the force, the slower will it be pulled back, and the more protracted the vibrations. The magnet is like a straying youth-the more attractive the influence over him, the sooner is he brought to steadiness.

Biot and Gay-Lussac, equipped with the necessary magnets and chronometers to count the times of vibration, started from the garden of the Conservatoire des Arts et Métiers on the 24th of August 1804. Their balloon was but small, and would only lift them about four thousand yards; and when they tried to make the desired observations upon the swinging needle, they were all but entirely frustrated, because of the rotatory motion of the balloon. They counted a few oscillations, and very soon came down ; I have heard it said, because one or both got frightened, but I find no documentary evidence on the point. One thing, however, is certain : when the next ascent was made, Gay-Lussac went up alone. This was on the 16th of September in the same year. He reached an altitude of nearly eight thousand yards, by throwing all useless appurtenances overboard; among other things he cast away a roughly-made chair, which fell in a thicket near to a yokel who was guarding some sheep. The sky was clear; but the balloon, nearly four miles high, was invisible. Imagine the astonishment of the natives ! It was voted that the seat had come from heaven ; but the knowing ones rejected this hypothesis on the grounds of the bad work that the article exhibited. The celestial chair-makers, said they, could not be such slovenly carpenters. The matter was under dispute till the newspapers told of the aëronaut's doings; and then the mystery vanished, no doubt much to the disappointment of the wondermongers.

The magnetic observations were a little more successful this time, but the results were not of a very decisive character: there were slight differences in the periods of vibration of the needle at different heights, but they did not follow a regular law of diminution; and on the whole it was concluded that the differences were accidental, and that the earth's magnetic force was the same at all altitudes above the surface. Such was the conclusion at the epoch of the observations; but since that time it has been discovered that temperature exerts a powerful influence over the rate of a needle's oscillations, cold quickening and warmth retarding them. If allowance be made for such an effect upon Gay-Lussac's needle, it results that his upper vibrations, made in a temperature of 16°, were relatively slower than his lower ones, which were made with the thermometer at 87°; and hence that the earth's magnetic force does diminish as we go upwards.

Besides these, the staple of his observations, Gay-Lussac recorded the indications of meteorological instruments, and deduced that the temperature, which, as is well known, decreases with elevation, varies less near the earth than in regions at a medium height, and that the humidity diminishes with extreme rapidity. The actual decrease of temperature which he observed was 7210 of the Fahrenheit scale in ascending 22,896 feet, or about a degree in 316 feet; a decrement very similar to that deduced from the best of mountain-observations. He collected air at his upper limit and analysed it, and found that while it contained the same proportions of oxygen and nitrogen as near the earth, it offered no trace of hydrogen; a fact of some importance in refuting certain theories of fiery meteors.

These French achievements made Italy jealous of her meteorological honours. The next scientific balloon ascent was made by a Neapolitan astronomer, one Carlo Brioschi, in company with the first of Italian aëronauts, Andreani. Their laudable ambition was to pass the limit attained by Gay-Lussac; so they went up and up, higher and higher, till they got into a highly rarefied region of the atmosphere, when their lofty intentions were unhappily frustrated ; the balloon had a greater pressure inside than out, from the expansion of the gas, and it burst, bringing them down with a run. Fortunately the torn and empty bag acted the part of a parachute and checked the velocity of their descent, or they must have been dashed to pieces, as Cocking was years after. As it was, falling as they did, slowly and upon soft ground, they came off with their lives; but Brioschi received injuries that eventually caused his death.

Whether this unfortunate experiment scared the philosophers off their quest for knowledge, or whether they were deterred from the research by another fear to be presently alluded to, I know not; but it is certain that for forty years nothing was done for science by the balloon in any systematic manner; nothing beyond the isolated facts gleaned now and then by the more philosophical of professional aëronauts. About 1841, however, the subject was noised again, this time in England. The British Association, ever ready to find the needful for experiments too costly for individual undertaking, was induced to vote a sum of 2501. for instruments and balloons to make a regular series of aërial investigations. Some of the money was spent, and once a balloon was reported ready to ascend, but for some unrecorded reason it never went off. I hope personal vanities and jealousies were not the disturbing cause; more than one squabble having arisen out of disputed honours in the matter of scientific skying, the thought will intrude itself.

Eight or nine years more passed before another aërial ship was

« PreviousContinue »