Wonderful Balloon Ascents/Part 3/Chapter 2
CHAPTER II.
ASCENT OF M. GAY-LUSSAC ALONE—EXCURSIONS OF MM. BARRAL AND BIXIO.
Respecting this ascent, Arago states that M. Gay-Lussac has reduced to their proper value the narratives of the physical pains which aeronauts say they suffer in lofty aerial ascents.
M. Gay-Lussac says:—"Having arrived at the most elevated point of my ascent, 21,000 feet above sea level, my respiration was rendered sensibly difficult, but I was far from experiencing any illness of a kind to make me descend. My pulse and my breathing were very quick; breathing very frequently in an extremely dry atmosphere, I should not have been surprised if my throat had been so dry as to make it painful to swallow bread."
After having finished his observations, which referred chiefly to the magnetic needle, with all the tranquillity of a doctor in his study, Gay-Lussac descended to the earth between Rouen and Dieppe, eighty leagues from Paris.
After the names of Robertson, Gay-Lussac, and Biot, science has registered those of Barral and Bixio, two men whose aeronautic achievements have enriched meteorology with more important discoveries, perhaps, than any we have yet mentioned.
These gentlemen had conceived the project of rising by means of a balloon to a great height, in order to study, with the assistance of the very best instruments in use in their day, a multitude of phenomena then imperfectly known. The subjects to which they were specially to direct their attention, were the law of the decrease of temperature in progress upwards, the discovery of whether the chemical composition of the atmosphere is the same throughout all its parts, the comparison of the strength of the solar rays in the higher regions of the atmosphere and on the surface of the earth, the ascertaining whether the light reflected and transmitted by the clouds is or is not polarised, &c.
All the preparations having been made in the garden of the Observatory at Paris, the ascent took place on the 29th of June, 1850, at 10.27 a.m., the balloon being filled with hydrogen gas. The first ascent was a signal failure. It was found that the weather being bad, the envelope of the balloon was torn in several places, and had to be mended in all haste. Immediately preceding the moment of ascent, a torrent of rain fell. But the voyagers were determined to ascend. They placed themselves in the car, and, when thrown off from the fastenings, they rose through the air with the speed of an arrow. The height to which the balloon reached made it suddenly dilate, and the network, which was much too small, was stretched to the utmost. The balloon was forced down upon them by the dilation, and one of them, in the endeavour to work the valve, made a rent in the lower part of the globe, from which the gas escaping almost over the heads of the travellers, nearly choked them. The escape of the gas had the usual result—the balloon descended rapidly, and fell in a vineyard near Lugny, where they were found by the peasants holding on to the trees by their legs and arms, and thus attempting to stop the horizontal advance of the car. They had risen to the height of over 17,000 feet, and they had descended from this height in from four to five minutes.
For all practical purposes, the ascent was a failure, and the aeronauts immediately commenced preparations for a new voyage, which took place a month afterwards. They rose to very great altitudes, but experienced no illness from the rarefied air. M. Bixio did not feel the sharp pains in the ears from which he had suffered on the former occasion. They passed through a mass of cloud 15,000 feet in thickness, and they had not yet passed quite through it, when at the height of over 21,000 feet from the ground, they began to descend, their descent being caused by a rent in the envelope of the balloon, from which the gas escaped. They might, in throwing out the last of their ballast, have, perhaps, prolonged for a little their sojourn in space, but the circumstances in which they were placed did not permit them to make many more scientific observations than those they had made, and thus they were obliged to submit to their fate. When they had reached their greatest height, there seemed to open up in the midst of the vaporous mass a brilliant space, from which they could see the blue of heaven. The polariscope, directed towards this region, showed an internal polarisation, but, when pointed to the side where the mist still prevailed, there was no polarisation.
An optical phenomenon of a remarkable kind was witnessed when the voyagers had attained their highest point. They saw the sun through the upper mists, looking quite white, as if shorn of its strength; and, at the same time, below the horizontal plane, below their horizon, and at an angular distance from the plane equal to that of the sun above it, they saw a second sun, which resembled the reflection of the actual sun in a sheet of water. It is natural to suppose that the second sun was formed by the reflection of the sun's rays upon the horizontal faces of the ice crystals floating in this high cloud.