Page:Encyclopædia Britannica, Ninth Edition, v. 1.djvu/216
pigeons were brought down to the ground. One was found to be dead, and the other, a carrier, was still living, but would not leave the hand when I attempted to throw it off, till after a quarter of an hour, it began to peck a piece of ribbon which encircled its neck, and was then jerked off the finger, and flew with some vigour towards Wolverhampton. One of the pigeons returned to Wolverhampton on Sunday, the 7th, and this is the only one that has been heard of."
Mr Glaisher found from his observation-book that the last observation was made at 29,000 feet, and that at this time the balloon was ascending at the rate of 1000 feet per minute; and that when he resumed his observations, it was descending at the rate of 2000 feet per minute, the interval being thirteen minutes. This gives 36,000 or 37,000 feet for the greatest height attained. Two other series of considerations led to the latter height, and there can be no doubt that the altitude of 37,000 feet, or 7 miles, was attained on this occasion.
In the ascent, April 18, 1863, 24,000 feet of elevation was reached. It was remarkable for the rapidity of the descent. At 2h. 44m., the balloon then at a height of 10,000 feet, Mr Coxwell suddenly caught sight of Beachy Head, and Mr Glaisher, looking over the edge of the car, saw the sea, apparently immediately underneath. There was no time to be lost, and Mr Coxwell hung on to the valve-line, telling Mr Glaisher to leave his instruments and do the same. The earth was reached at 2h. 48m., the two miles of descent having been effected in four minutes. The balloon struck the ground near Newhaven, with a terrible crash, but, from the free use of the valve-line, it was so crippled that it did not move afterwards. All the instruments, of the value of more than £25, including some that were unreplaceable, were broken, and Mr Glaisher was hurt. In the descent, after the first high ascent on July 17, 1862, the earth was struck with so much violence that most of the instruments were broken, and Mr Glaisher (who was closed in by his observing-board) was a good deal hurt then. In subsequent ascents, therefore, boxes were used filled with small mattresses, in which the instruments could be hurriedly placed, and the board was so arranged that it could be turned over and hung outside the car. These improvements had the effect of diminishing the danger to himself and the chance of breakage of the instruments, but in the Newhaven descent there was not sufficient time to put them in practice.
The circumstances met with in the ascent, June 26, 1863, were so remarkable that a short account cannot be omitted. The morning was at first very bright and fine, but between 11 and 12 o'clock a change took place; the sky became covered with clouds, and the wind rose and blew strongly, so that great difficulty was experienced in completing the inflation. At 1h. 3m. the balloon left; in four minutes, at 4000 feet high, cloud was entered. Mr Glaisher expected soon to break through it, and enter into bright sunshine as usualy, but nothing of the sort took place, as, on emergence, clouds were seed both above and below. At 9000 feet the sighing and moaning of the wind were heard, and Mr Glaisher satisfied himself that this was due, not to the cordage of the balloon, but to opposing currents. At this time the sun was seen faintly, but instead of its brillliance increasing, although the balloon was then two miles high, a fog was entered, and the sight of the sun lost. The balloon next passed through a dry fog, which was left at 12,000 feet, and after the sun had been seen faintly for a little time, a wetting fog was entered.
"At 15,000 feet," Mr Glaisher proceeds, "we were still in fog, but it was not so wetting. At 16,000 feet we entered a dry fog; at 17,000 feet saw faint gleams of the sun, and heard a train. We were now about 3 miles high; at this time we were not in cloud, but clouds were below us; others were on our level at a distance, and yet more above us. We looked with astonishment at each other, and said as we were rising steadily we surely must soon pass through them. At 17,500 feet we were again enveloped in fog, which became wetting at 18,500 feet; we left this cloud below at 19,600 feet. At 20,000 feet the sun was just visible. We were now approaching 4 miles high; dense clouds were still above us; for a space of 2000 to 3000 feet we met with no fog, but on passing above 4 miles our attention was first attracted to a dark mass of clouds, and then to another on our level; both these clouds had fringed edges—they were both nimbi. Without the slightest doubt both these clouds were regular rain-clouds. Whilst looking at them we again lost sight of everything, being eveloped in fog whilst passing upwards through 1000 feet. At 22,000 feet we again emerged, and were above clouds on passing above 23,000 feet. At six minutes to 2 o'clock we heard a railway train; the temperature here was 18°. I wished still to ascend to find the limits of this vapour, but Mr Coxwell said, 'We are too short of sand; I cannot go higher; we must not even stop here.' I was therefore most reluctantly compelled to abandon the wish, and looked searchingly around. At this highest point, in close proximity to us, were rain-clouds; below us dense fog. I was again reminded that we must not stop. With a hasty glance everywhere, above, below, around, I saw the sky nearly covered with dark clouds of a stratus character, with cirri still higher, and small spaces of blue sky between them. The blue was not the blue of 4 or 5 miles high as I had always before seen it, but a faint blue, as seen from the earth when the air is charged with moisture."
In the downward journey an even more remarkable series of circumstances was met with; for a fall of rain was passed through, and then below it a snow-storm, the flakes being entirely composed of spiculæ of ice and innumerable snow-crystals. On reaching the ground near Ely the lower atmosphere was found to be thick, misty, and murky. At Wolverton the afternoon was cold, raw, and disagreeable for a summer's day. The fact of rain-clouds extending layer above layer to a height of 4 miles, was one never hitherto regarded as possible; and the occurrence of rain and snow, and the latter underneath the former, and all happening on a day in the very middle of summer, formed a series of most curious and unexpected phenomena.
Mr Glaisher having, in one of his descents, which took place near sunset, observed that the temperature was the same through a very considerable height, it occurred to him that after dark it was quite possible that, for some elevation above the earth's surface, the temperature might even increase with increase of height; and to determine this he arranged for some ascents to be made after sunset, so that the temperature during the night might be observed. For this purpose he procured a couple of Davy lamps, which answered their object satisfactorily. Accordingly, on October 2, 1865, an ascent was made from Woolwich Arsenal, the time of starting being about three-quarters of an hour after the sun had set. The temperature on the earth was 56°, and it steadily increased to 59°.6 at the height of 1900 feet. This was established conclusively by repeated ups and downs, the temperature falling as the balloon descended. The view of London lighted up, as seen from the balloon in this ascent, the night being clear, was most wonderful. A second night ascent was made from the same place on December 2, 1865, and the balloon left the earth 2¾ hours after sunset. On this occasion the temperature did not rise, but the decrease, though steady, was small. In an ascent from Windsor on May 29, 1866, the balloon was kept up till half-past eight o'clock, and the temperature was found to decrease as the earth was approached during the last 900 feet. In this last ascent no paid aeronaut was employed, as Mr Westcar, of the Royal Horse Guards, undertook the management of the balloon. In the preceding five ascents Mr Orton, of Blackwall, was employed as aeronaut.
It has been found necessary in the present notice to allude merely to the more striking points noticed in Mr Glaisher's twenty-eight ascents. The number of observations made by him was of course great, and it is only necessary here to repeat that they are to be found in the Reports of the British Association for the Advancement of Science,