Wonderful Balloon Ascents/Part 3/Chapter 3
THE ASCENTS OF MESSRS. WELSH, GLAISHER, AND COXWELL.
The most recent balloon ascents in England deserving attention have been undertaken for scientific objects, and in this country, more than in any other, it may be said that the conquest of the air has been made to serve a practical end.
In July, 1852, the Committee of the Kew Observatory resolved to undertake a number of balloon voyages. This resolution was approved of by the British Association for the Advancement of Science, and the necessary instruments for making a number of meteorological observations were prepared. The balloon employed was that of Mr. Green, who was accompanied in his ascents by Mr. Welsh. The greatest height to which Mr. Welsh rose was on the fourth ascent which took place on the 10th of November, 1852. The balloon rose 22,930 feet, and the lowest temperature observed was 26° below zero.
It is to Mr. Glaisher and Mr. Coxwell, however, that the highest honours of scientific aerostation belong. The ascents made by these gentlemen—Mr. Glaisher being the scientific observer, and Mr. Coxwell the practical aeronaut—have become matters of history. Not only did they, in the course of a large number of ascents undertaken under the auspices of the British Association, succeed in gathering much valuable meteorological information, but they reached a greater height than that ever gained on any previous or subsequent occasion, and penetrated into that distant region of the skies in which it has been satisfactorily proved that no life can be long maintained. It was on the 5th of September, 1862, that Mr. Glaisher and Mr. Coxwell made the famous ascent in which they reached the greatest height ever attained by an aeronaut, and were so nearly sacrificed to their unselfish daring. Mr. Glaisher has given an admirable account of this ascent, which took place from Wolverhampton. He says:—"Our ascent had been delayed, owing to the unfavourable state of the weather. It commenced at three minutes past one p.m., the temperature of the air being 59°, and the dew-point 48°. At the height of one mile the temperature was 41° and the dew-point 38°. Shortly afterwards clouds were entered of about 1,100 feet in thickness. Upon emerging from them at seventeen minutes past one, I tried to take a view of their surface with the camera, but the balloon was ascending too rapidly and spiraling too quickly to allow me to do so. The height of two miles was reached at twenty-one minutes past one. The temperature of the air had fallen to 32° and the dew-point to 26°. The third mile was passed at twenty-eight minutes past one, with an air temperature of 18°, and a dew-point of 13°. The fourth mile was passed at thirty-nine minutes past one, with an air temperature of 8°, and a dew-point of minus 6 degrees and the fifth mile about ten minutes later, with an air temperature minus 5°, and a dew-point minus 36°.
"Up to this time I had experienced no particular inconvenience. When at the height of 26,000 feet I could not see the fine column of the mercury in the tube; then the fine divisions on the scale of the instrument became invisible. At that time I asked Mr. Coxwell to help me to read the instruments, as I experienced a difficulty in seeing them. In consequence of the rotary motion of the balloon, which had continued without ceasing since the earth was left, the valve line had become twisted, and he had to leave the car, and to mount into the ring above to adjust it. At that time I had no suspicion of other than temporary inconvenience in seeing. Shortly afterwards I laid my arm upon the table, possessed of its full vigour; but directly after, being desirous of using it, I found it powerless. It must have lost its power momentarily. I then tried to move the other arm, but found it powerless also. I next tried to shake myself, and succeeded in shaking my body. I seemed to have no legs. I could only shake my body. I then looked at the barometer, and whilst I was doing so my head fell on my left shoulder. I struggled, and shook my body again, but could not move my arms. I got my head upright, but for an instant only, when it fell on my right shoulder; and then I fell backwards, my back resting against the side of the car, and my head on its edge. In that position my eyes were directed towards Mr. Coxwell in the ring. When I shook my body I seemed to have full power over the muscles of the back, and considerable power over those of the neck, but none over my limbs. As in the case of the arms, all muscular power was lost in an instant from my back and neck. I dimly saw Mr. Coxwell in the ring, and endeavoured to speak, but could not do so; when in an instant intense black darkness came over me, and the optic nerve lost power suddenly. I was still conscious, with as active a brain as whilst writing this. I thought I had been seized with asphyxia, and that I should experience no more, as death would come unless we speedily descended. Other thoughts were actively entering my mind when I suddenly became unconscious, as though going to sleep. I could not tell anything about the sense of hearing: the perfect stillness of the regions six miles from the earth—and at that time we were between six and seven miles high—is such that no sound reaches the ear. My last observation was made at 29,000 feet, about fifty-four minutes past one. I suppose two or three minutes elapsed between my eyes becoming insensible to seeing the fine divisions and fifty-four minutes past one, and that other two or three minutes elapsed before I became unconscious; therefore I think that took place about fifty-six or fifty-seven minutes past one. Whilst powerless I heard the words 'temperature,' and 'observation,' and I knew Mr. Coxwell was in the car, speaking to me, and endeavouring to rouse me; and therefore consciousness and hearing had returned. I then heard him speak more emphatically, but I could not speak or move. Then I heard him say, 'Do try; now do!' Then I saw the instruments dimly, next Mr. Coxwell, and very shortly I saw clearly. I rose in my seat and looked round, as though waking from sleep, and said to Mr. Coxwell, 'I have been insensible.' He said, 'Yes; and I too, very nearly.' I then drew up my legs, which had been extended out before me, and took a pencil in my hand to note my observations. Mr. Coxwell informed me that he had lost the use of his hands, which were black, and I poured brandy over them. I resumed my observations at seven minutes past two. I suppose three or four minutes were occupied from the time of my hearing the words 'temperature' and 'observation,' until I began to observe. If so, then returning consciousness came at four minutes past two, and that gives about seven minutes of total insensibility. Mr. Coxwell told me that in coming from the ring he thought for a moment that I had laid back to rest myself; that he spoke to me without eliciting a reply; that he then noticed that my legs projected, and my arms hung down by my side. That my countenance was serene and placid, without earnestness or anxiety, he had noticed before going into the ring. It then struck him that I was insensible. He wished then to approach me, but could not, and he felt insensibility coming over himself. He became anxious to open the valve, but, in consequence of having lost the use of his hands, he could not; and ultimately he did so by seizing the cord with his teeth and dipping his head two or three times. No inconvenience followed our insensibility. When we dropped it was in a country where no accommodation of any kind could be obtained, so that we had to walk between seven and eight miles. At the time of ceasing our observations the ascent was at the rate of 1,000 feet per minute, and on resuming observations the descent was at the rate of 2,000 feet per minute. These two positions must be connected, having relation to the interval of time which elapsed between them; and they can scarcely be connected at a point less than 36,000 or 37,000 feet high. Again, a very delicate minimum thermometer was found to read minus 12°, and that reading would indicate an elevation exceeding 36,000 feet. There cannot be any doubt that the balloon attained the great height of seven miles—the greatest ever reached. In this ascent six pigeons were taken up. One was thrown out at three miles. It extended its wings, and dropped like a piece of paper. A second at four miles, and it flew with vigour. A third between four and five miles, and it fell downwards. A fourth was thrown out at four miles in descending, and it alighted on the top of the balloon. Two were brought to the ground. One was dead, and the other was ill, but recovered so as to fly away in a quarter of an hour."
The results gathered by Mr. Glaisher from his numerous ascents are very interesting. He found that in no instance did the temperature of the air decrease uniformly with the increase of height. In fact, the decrease in the first mile is double that in the second, and nearly four times as great as the change of temperature in the fifth mile. The distribution of aqueous vapour in the air is no less remarkable. The temperature of the dew-point on leaving the earth decreases less rapidly than the temperature of the air; so that the difference between the two temperatures becomes less and less, till the vapour or cloud plane is reached, when they are usually together, and always most nearly approach each other, and that point is usually at about the height of one mile. On leaving the upper surface of cloud, the dew point decreases more rapidly than the air, and at extremely high situations the difference between the two temperatures is wonderfully great, indicating an extraordinary degree of dryness, and an almost entire absence of water. Under these circumstances, the presence of cirrus clouds far above this dry region, apparently as much above as when viewed from the earth, is very remarkable, and leads to the conclusion that they are not composed of water.
In the propagation of sound, M. Glaisher made many curious experiments. In one ascent (July 17th) he found, when at a distance of 11,800 feet above the earth, that a band was heard; at a height of 22,000 feet, a clap of thunder was heard; and at a height of 10,070 feet, the report of a gun was heard. On one occasion, he heard the dull hum of London at a height of 9,000 feet above the city, and on another occasion, the shouting of many thousands of persons could not be heard at the height of 4,000 feet.