British Quarterly Review, American Edition, Vol. LIV / July and October, 1871

by Various

There is no subject of greater moment to aeronauts than the determination of the atmospheric currents. Upon this question in a great measure depends the utility of ballooning as an art. We should certainly consider that ocean navigation was in a despicable condition if the utmost we could do for a vessel was to commit it, preciously freighted with our own persons, to the wind and waves, without a sail to propel it or a rudder to guide it in any particular direction. Yet this is pretty much the state of aerial seamanship, except for purposes of vertical travelling. If it could be ascertained that streams flowed to different quarters at different elevations—river rolling over river—then it might be easy to book our balloon for some special point of the compass. But the atmosphere is comparatively unexplored in this respect, and it will require long study before any definite conclusions can be formed, even if such should be ever realized.

That there is some degree of certainty in air-currents may be indicated by a curious fact mentioned by Flammarion, namely, that the traces of his various voyages are all represented by lines which had a tendency to curve in one and the same general direction. 'Thus,' says he, 'on the 23rd June, 1867, the balloon started with a north wind directly towards the south-south-west, and, after a while, due south-west, when we descended. A similar result was observed in every excursion, and the fact led me to believe that above the soil of France the currents of the atmosphere are constantly deviated circularly, and in a south-west-north-east-south direction.'

Still more curious is a fact which Mr. Glaisher may be said to have discovered.

We are accustomed to talk much of the Gulf Stream. It is as popular a marine phenomenon as the Great Sea Serpent. For some time it has figured in meteorology as the subtle agent to which all climatic eccentricities, and not a few climatic advantages, are ascribed; but what shall we say to a genuine 'aeria Gulf Stream?' What, to a stream flowing through the atmosphere in kindly correspondence with the beneficent current which sweeps through the Atlantic below?

On the 12th January, 1864, Mr. Glaisher left the earth, where a south-east wind was prevailing. At a height of 1,300 feet he was surprised to enter a warm current, 3,000 feet in thickness, which was flowing from the south-west, that is, in the direction of the Gulf Stream itself. At the elevation in question the temperature, according to the usual calculation, should have been 4° or 5° lower than that at the ground, whereas it was 3½° higher. In the region above, cold reigned, for finely-powdered snow was falling into this atmospheric river. Here, therefore, was a stream of heated air previously unsuspected, which, if its course is steady, as it appears to be during winter, constitutes a prodigious accession to our resources, and adds another to the many meteorological blessings the world enjoys.

'The meeting with this south-west current (writes Mr. Glaisher) is of the highest importance, for it goes far to explain why England possesses a winter temperature so much higher than our northern latitudes. Our high winter temperature has hitherto been mostly referred to the influence of the Gulf Stream. Without doubting the influence of this natural agent, it is necessary to add the effect of a parallel atmospheric current to the oceanic current coming from the same regions—a true aerial Gulf Stream. This great energetic current meets with no obstruction in coming to us, or to Norway, but passes over the level Atlantic without interruption from mountains. It cannot, however, reach France without crossing Spain and the lofty range of the Pyrenees, and the effect of these cold mountains in reducing its temperature is so great that the former country derives but little warmth from it.'

The velocity of these atmospheric streams must, of course, differ considerably; but, however rapid may be their motion, the balloonist will not fail to notice the feeling of personal immobility which gives such a peculiar character to aerial travelling. We can hardly realize the idea of being transported, say, from London to Dover, without experiencing sundry jars of the muscles or tremors of the nerves, even if we escape, as is by no means certain, the chances of a collision; but M. Flammarion remarks in reference to one of his journies, that the distance accomplished was a hundred and twenty miles, 'during the whole of which time we never felt ourselves in motion at all.' No better illustration of this exemption from the jerks and joltings of terrestrial locomotion could be given than a simple experiment. A tumbler was filled with water till the liquid stood bulging over the brim. The balloon was travelling with the velocity of a railway train, and sometimes rising, sometimes falling, through hundreds of feet at a time, yet not a single drop of the fluid was swung out of the glass!

Striking as the fact is, it would be still more surprising if it were otherwise; for, having once entered a current of air, and surrendered our machine to its guidance, we become, as it were, part of the medium in which we are immersed. The balloon has no longer any will of its own, or of its occupants, except for purposes of ascent or descent. It glides along with the stream, and, coming athwart no obstructions, it knows none of the bumpings to which more grovelling vehicles are exposed. Hence results another consequence which will scarcely escape attention, namely, that here, in the very place of winds, we experience no wind whatever. You may sit in the car of a balloon without undergoing much danger from draughts. There are no fierce gales to encounter, and therefore there are no weather-beaten mariners aloft. If we come to a spot where two breezes meet in battle, or, if two currents of differing directions were so sharply defined that the upper part of the machine could emerge into the superior stream whilst the lower part was in the keeping of the inferior, then very unpleasant results might ensue; but these are not events which aerial navigators have frequently to record in the serener regions aloft.

And as all motion seems to have ceased, except what is due to the rotatory action of the balloon, so all sound appears to have expired. On earth we have nothing to compare with the awful stillness of these airy solitudes. Some noise—be it the sighing of the wind, the pattering of the rain, the fall of a crumbling particle of rock—will break the tranquillity of the vale, the loneliest wilderness, the loftiest peak. But here nature appears to be voiceless, and silence, 'the prelude of that which reigns in the interplanetary space,' seems to be a consecrated thing, as if it were destined to remain uninterrupted until the Trumpet of Judgment shall wake the world.

But did we say we were in absolute solitude? If so, imagine the startled look of an aeronaut when, on issuing from a cloud, he sees before him, at the distance of some thirty or forty yards, the figure of another balloon! If a feeling of horror creeps over him at the sight, he might well be pardoned, for his first thought would doubtless be that it was some phantom of the air sent to lure him to destruction, as the Flying Dutchman is reported to do with mariners at sea. One remarkable feature, however, instantly attracts his attention. The car of the stranger is placed in the centre of a huge disc, consisting of several concentric circles—the interior one being of yellowish white, the next pale blue, the third yellow, followed by a ring of greyish red, and, finally, by one of light violet. That car, too, is occupied. Its tenants are engaged in returning the scrutiny, and their attitudes express equal surprise. By-and-bye, one of them lifts his hand; but that is just what one of the aeronauts has done. Another motion is made, and this is imitated to the letter. A laugh from the living voyagers follows. They have discovered that the stranger is an optical apparition, for on examination it is found to correspond with their own machine, line for line, rope for rope, and man for man, except that they, the living ones, are not surrounded by a glory as if they were resplendent saints.