Of all the wonderful discoveries which modern science has given birth to, there is perhaps not one which has been applied to useful purposes on a scale so unexpectedly contracted as that by which we are enabled to penetrate into the immense ocean of air with which our globe is surrounded, and to examine the physical phenomena which are manifested in its upper strata. One would have supposed that the moment the power was conferred upon us to leave the surface of the earth, and rise above the clouds into the superior regions, a thousand eager inquirers would present themselves as agents in researches in a region so completely untrodden, if such a term may here be permitted.

Nevertheless, this great invention of aerial navigation has remained almost barren. If we except the celebrated aerial voyage of Gay-Lussac in 1804, the balloon, with its wonderful powers, has been allowed to degenerate into a mere theatrical exhibition, exciting the vacant and unreflecting wonder of the multitude. Instead of being an instrument of philosophical research, it has become a mere expedient for profit in the hands of charlatans, so much so, that, on the occasion to which we are now about to advert, the persons who engaged in the project incurred failure, and risked their lives, from their aversion to avail themselves of the experience of those who had made aerostation a mere spectacle for profit. They thought that to touch pitch they must be defiled, and preferred danger and the risk of failure to such association.

It is now about two months since M. Barral, a chemist of some distinction at Paris, and M. Bixio, a member of the Legislative Assembly (whose name will be remembered in connection with the bloody insurrection of June, 1848, when, bravely and humanely discharging his duty in attempting to turn his guilty fellow-citizens from their course, he nearly shared the fate of the Archbishop, and was severely wounded), resolved upon making a grand experiment with a view to observe and record the meteorological phenomena of the strata of the atmosphere, at a greater height and with more precision than had hitherto been accomplished. But from the motives which we have explained, the project was kept secret, and it was resolved that the experiment should be made at an hour of the morning, and under circumstances, which would prevent it from degenerating into an exhibition. MM. Arago and Regnault undertook to supply the aerial voyagers with a programme of the proposed performance, and instruments suited to the projected observations. M. Arago prepared the programme, in which was stated clearly what observations were to be made at every stage of the ascentional movement.

It was intended that the balloon should be so managed as to come to rest at certain altitudes, when barometric, thermometric, hygrometric, polariscopic, and other observations, were to be taken and noted; the balloon after each series of observations to make a new ascent.

The precious instruments by which these observations were to be made were prepared, and in some cases actually fabricated and graduated, by the hands of M. Regnault himself.

To provide the balloon and its appendages, recourse was had to some of those persons who have followed the fabrication of balloons as a sort of trade, for the purposes of exhibition.

In this part of their enterprise the voyagers were not so fortunate, as we shall presently see, and still less so in having taken the resolution to ascend alone, unaccompanied by a practiced Æronaut. It is probable that if they had selected a person, such as Mr. Green, for example, who had already made frequent ascents for the mere purpose of exhibition, and who had become familiar with the practical management of the machine, a much more favorable result would have ensued. As it was, the two voyagers ascended for the first time, and placed themselves in a position like that of a natural philosopher, who, without previous practice, should undertake to drive a locomotive, with its train on a railway at fifty miles an hour, rejecting the humble but indispensable aid of an experienced engine-driver.

The necessary preparations having been made, and the programme and the instruments prepared, it was resolved to make the ascent from the garden behind the Observatory at Paris, a plateau of some elevation, and free from buildings and other obstacles, at day-break of Saturday, the 29th June. At midnight the balloon was brought to the spot, but the inflation was not completed until nearly 10 o’clock, A.M.

It has since been proved that the balloon was old and worn, and that it ought not to have been supplied for such an occasion.

It was obviously patched, and it is now known that two seamstresses were employed during the preceding day in mending it, and some stitching even was found necessary after it had arrived at the Observatory.

The net-work which included and supported the car was new, and not originally made with a view to the balloon it inclosed, the consequences of which will be presently seen.

The night, between Friday and Saturday, was one of continual rain, and the balloon and its netting became thoroughly saturated with moisture. By the time the inflation had been completed, it became evident that the net-work was too small; but in the anxiety to carry into effect the project, the consequences of this were most unaccountably overlooked. We say unaccountably, because it is extremely difficult to conceive how experimental philosophers and practiced observers, like MM. Arago and Regnault, to say nothing of numerous subordinate scientific agents who were present, did not anticipate what must have ensued in the upper regions of the air. Nevertheless, such was the fact.

On the morning of Saturday, the instruments being duly deposited in the car, the two enterprising voyagers placed themselves in it, and the balloon, which previously had been held down by the strength of twenty men, was liberated, and left to plunge into the ocean of air, at twenty-seven minutes after ten o’clock.

The weather, as we have already stated, was unfavorable, the sky being charged with clouds. As it was the purpose of this project to examine much higher regions of the atmosphere than those which it had been customary for aeronautic exhibitors to rise to, the arrangements of ballast and inflation which were adopted, were such as to cause the ascent to be infinitely more rapid than in the case of public exhibitions; in short, the balloon darted upward with the speed of an arrow, and in two minutes from the moment it was liberated, that is to say, at twenty-nine minutes past ten, plunged into the clouds, and was withdrawn from the anxious view of the distinguished persons assembled in the garden of the Observatory.

While passing through this dense cloud, the voyagers carefully observed the barometer, and knew by the rapid fall of the mercury that they were ascending with a great velocity. Fifteen minutes elapsed before they emerged from the cloud; when they did so, however, a glorious spectacle presented itself. The balloon, emerging from the superior surface of the cloud, rose under a splendid canopy of azure, and shone with the rays of a brilliant sun. The cloud which they had just passed, was soon seen several thousand feet below them. From the observations taken with the barometer and thermometer, it was afterward found that the thickness of the cloud through which they had passed, was 9800 feet—a little less than two miles. On emerging from the cloud, our observers examined the barometer, and found that the mercury had fallen to the height of 18 inches; the thermometer showed a temperature of 45° Fahr. The height of the balloon above the level of the sea was then 14,200 feet. At the moment of emerging from the cloud, M. Barral made polariscopic observation, which established a fact foreseen by M. Arago, that the light reflected from the surface of the clouds, was unpolarized light.

The continued and somewhat considerable fall of the barometer informed the observers that their ascent still continued to be rapid. The rain which had previously fallen, and which wetted the balloon, and saturated the cordage forming the net-work, had now ceased, or, to speak more correctly, the balloon had passed above the region in which the rain prevailed. The strong action of the sun, and almost complete dryness of the air in which the vast machine now floated, caused the evaporation of the moisture which enveloped it. The cordage and the balloon becoming dry, and thus relieved of a certain weight of liquid, was affected as though a quantity of ballast had been thrown out, and it darted upward with increased velocity.

It was within one minute of eleven, when the observers finding the barometer cease the upward motion, and finding that the machine oscillated round a position of equilibrium by noticing the bearing of the sun, they found the epoch favorable for another series of observations. The barometer there indicated that the balloon had attained the enormous height of 19,700 feet. The moisture which had invested the thermometer had frozen upon it, and obstructed, for the moment, observations with it. It was while M. Barral was occupied in wiping the icicles from it, that, turning his eye upward, he beheld what would have been sufficient to have made the stoutest heart quail with fear.

To explain the catastrophe which at this moment, and at nearly 20,000 feet above the surface of the earth, and about a mile above the highest strata of the clouds, menaced the voyagers, we must recur to what we have already stated in reference to the balloon and the net-work. As it was intended to ascend to an unusual altitude, it was of course known, that in consequence of the highly rarefied state of the atmosphere, and its very much diminished pressure, the gas contained in the balloon would have a great tendency to distend, and, consequently, space must be allowed for the play of this effect. The balloon, therefore, at starting, was not nearly filled with gas, and yet, as we have explained it, very nearly filled the net-work which inclosed it. Is it not strange that some among the scientific men present did not foresee, that when it would ascend into a highly rarefied atmosphere, it would necessarily distend itself to such a magnitude, that the netting would be utterly insufficient to contain it? Such effect, so strangely unforeseen, now disclosed itself practically realized to the astonished and terrified eyes of M. Barral.

The balloon, in fact, had so swelled as not only completely to fill the netting which covered it, but to force its way, in a frightful manner, through the hoop under it, from which the car, and the voyagers were suspended.

In short, the inflated silk protruding downward through the hoop, now nearly touched the heads of the voyagers. In this emergency the remedy was sufficiently obvious.

The valve must be opened, and the balloon breathed, so as to relieve it from the over-inflation. Now, it is well known, that the valve in this machine is placed in a sort of sleeve, of a length more or less considerable, connected with the lower part of the balloon, through which sleeve the string-of the valve passes. M. Barral, on looking for this sleeve, found that it had disappeared. Further search showed that the balloon being awkwardly and improperly placed in the inclosing net-work, the valve-sleeve, instead of hanging clear of the hoop, had been gathered up in the net-work above the hoop; so that, to reach it, it would have been necessary to have forced a passage between the inflated silk and the hoop.

Now, here it must be observed, that such an incident could never have happened to the most commonly-practiced balloon exhibitor, whose first measure, before leaving the ground, would be to secure access to, and the play of the valve. This, however, was, in the present case, fatally overlooked. It was, in fine, now quite apparent, that either of two effects must speedily ensue—viz.: either the car and the voyagers would be buried in the inflated silk which was descending upon them, and thus they would he suffocated, or that the force of distention must burst the balloon. If a rupture were to take place in that part immediately over the car, then the voyagers would be suffocated by an atmosphere of hydrogen; if it should take place at a superior part, then the balloon, rapidly discharged of its gas, would be precipitated to the earth, and the destruction of its occupants rendered inevitable.

Under these circumstances the voyagers did not lose their presence of mind, but calmly considered their situation, and promptly decided upon the course to be adopted. M. Barral climbed up the side of the car, and the net-work suspending it, and forced his way through the hoop, so as to catch hold of the valve-sleeve. In this operation, however, he was obliged to exercise a force which produced a rent in a part of the silk below the hoop, and immediately over the car. In a moment the hydrogen gas issued with terrible force from the balloon, and the voyagers found themselves involved in an atmosphere of it.

Respiration became impossible, and they were nearly suffocated. A glance at the barometer, however, showed them that they were falling to the ground with the most fearful rapidity.

During a few moments they experienced all the anguish attending asphyxia. From this situation, however, they were relieved more speedily than they could then have imagined possible; but the cause which relieved them soon became evident, and inspired them with fresh terrors.

M. Barral, from the indications of the barometer, knew that they were being precipitated to the surface of the earth with a velocity so prodigious, that the passage of the balloon through the atmosphere dispelled the mass of hydrogen with which they had been surrounded.

It was, nevertheless, evident that the small rent which had been produced in the lower part of the balloon, by the abortive attempt to obtain access to the valve, could not have been the cause of a fall so rapid.

M. Barral, accordingly, proceeded to examine the external surface of the balloon, as far as it was visible from the car, and, to his astonishment and terror, he discovered that a rupture had taken place, and that a rent was made, about five feet in length, along the equator of the machine, through which, of course, the gas was now escaping in immense quantities. Here was the cause of the frightful precipitation of the descent, and a source of imminent danger in the fall.

M. Barral promptly decided on the course to be taken.

It was resolved to check the descent by the discharge of the ballast, and every other article of weight. But this process, to be effectual, required to be conducted with considerable coolness and skill. They were some thousand feet above the clouds. If the ballast were dismissed too soon, the balloon must again acquire a perilous velocity before it would reach the earth. If, on the other hand, its descent were not moderated in time, its fall might become so precipitate as to be ungovernable. Nine or ten sand-bags being, therefore, reserved for the last and critical moment, all the rest of the ballast was discharged. The fall being still frightfully rapid, the voyagers cast out, as they descended through the cloud already mentioned, every article of weight which they had, among which were the blankets and woolen clothing which they had brought to cover them in the upper regions of the atmosphere, their shoes, several bottles of wine, all, in fine, save and except the philosophical instruments. These they regarded as the soldier does his flag, not to be surrendered save with life. M. Bixio, when about to throw over a trifling apparatus, called an aspirator, composed of copper, and filled with water, was forbidden by M. Barral, and obeyed the injunction.

They soon emerged from the lower stratum of the cloud, through which they had fallen in less than two minutes, having taken fifteen minutes to ascend through it. The earth was now in sight, and they were dropping upon it like a stone. Every weighty article had been dismissed, except the nine sand-bags, which had been designedly reserved to break the shock on arriving at the surface. They observed that they were directly over some vine-grounds near Lagny, in the department of the Seine and Marne, and could distinctly see a number of laborers engaged in their ordinary toil, who regarded with unmeasured astonishment the enormous object about to drop upon them. It was only when they arrived at a few hundred feet from the surface that the nine bags of sand were dropped by M. Barral, and by this manoeuvre the lives of the voyagers were probably saved. The balloon reached the ground, and the car struck among the vines. Happily the wind was gentle; but gentle as it was it was sufficient, acting upon the enormous surface of the balloon, to drag the car along the ground, as if it were drawn by fiery and ungovernable horses. Now arrived a moment of difficulty and danger, which also had been foreseen and provided for by M. Barral. If either of the voyagers had singly leaped from the car, the balloon, lightened of so much weight, would dart up again into the air. Neither voyager would consent, then, to purchase his own safety at the risk of the other. M. Barral, therefore, threw his body half down from the car, laying hold of the vine-stakes, as he was dragged along, and directing M. Bixio to hold fast to his feet. In this way the two voyagers, by their united bodies, formed a sort of anchor, the arms of M. Barral playing the part of the fluke, and the body of M. Bixio that of the cable.

In this way M. Barral was dragged over a portion of the vineyard rapidly, without any other injury than a scratch or contusion of the face, produced by one of the vine-stakes.

The laborers just referred to meanwhile collected, and pursued the balloon, and finally succeeded in securing it, and in liberating the voyagers, whom they afterward thanked for the bottles of excellent wine which, as they supposed, had fallen from the heavens, and which, wonderful to relate, had not been broken from the fall, although, as has been stated, they had been discharged above the clouds. The astonishment and perplexity of the rustics can be imagined on seeing these bottles drop in the vineyard.

This fact also shows how perpendicularly the balloon must have dropped, since the bottles dismissed from such a height, fell in the same field where, in a minute afterward, the balloon also dropped.

The entire descent from the altitude of twenty thousand feet was effected in seven minutes, being at the average rate of fifty feet per second.

In fine, we have to report that these adventurous partisans of science, nothing discouraged by the catastrophe which has occurred have resolved to renew the experiment under, as may he hoped, less inauspicious circumstances; and we trust that on the next occasion they will not disdain to avail themselves of the co-operation and presence of some one of those persons, who having hitherto practiced aerial navigation for the mere purposes of amusement, will, doubtless, be too happy to invest one at least of their labors with a more useful and more noble character.

[From the Dublin University Magazine.]