Page:Encyclopædia Britannica, Ninth Edition, v. 1.djvu/213

Rh ASCENTS.] AERONAUTICS 195 scent of M. Bixio id Barral i June &amp;gt;, 1850. n July 7, 1850. r Welsh s ur as- nts in ritish As- iciation ppoint.s alloon mimittee. nut experience any sensible variation at heights from the earth s surface which we can attain to. Gay-Lussac also brought down air collected at the height of nearly 23,000 feet, and on analysis it appeared that its constitu tion was the same as that of air collected at the earth s surface. At the time of leaving the earth the thermometer stood at 82 Fahr., and at the highest point reached (23,000 feet) it was 14 0&amp;lt; 9 Fahr. Gay-Lussac remarked that at his highest point there were still clouds above him. From 1804 to 1850 there is no record of any scientific ascents in balloons having been undertaken. In the latter year MM. Bixio and Barral made two ascents for this pur pose. They ascended from the Paris Observatory on June 29, 1850, at 10.27 A.M., the balloon being inflated with hydrogen gas. The day was a rough one, and the ascent took place suddenly, without any previous attempt having been made to test the ascensional force of the balloon. When liberated, it rose with great rapidity, and becoming fully inflated it pressed upon the network, bulging out at the top and bottom. As the ropes by which the car was suspended were too short, the balloon soon covered the travellers like an immense hood. In endeavouring to secure the valve-rope, a rent was made in the balloon, and the gas escaped so close to the faces of the voyagers as almost to suffocate them. Finding that they were descend ing then too rapidly, they threw overboard everything available, including their coats, and only excepting the instruments. The ground was reached at lOh. 45m., near Lagny. Of course no observations were made. MM. Bixio and Barral determined to ascend again with out delay, and accordingly, on July 27, 1850, they repeated the experiment. The ascent was remarkable on account of the extreme cold met with. At about 20,000 feet the temperature was 15 Fahr., the balloon being enveloped in cloud; but on emerging from the cloud, at 23,000 feet, the temperature sank to - 38 Fahr., no less than 53 Fahr. below that experienced by Gay-Lussac at the same eleva tion. The existence of these very cold clouds served to explain certain meteorological phenomena that were ob served on the earth both the day before and the day after the ascent. Some pigeons were taken up in this, as in most other high ascents, and liberated ; they showed a re luctance to leave the car, and then fell heavily downwards. In July 1852 the committee of the Kew Observatory resolved to institute a series of balloon ascents, with the view of investigating such meteorological and physical phenomena as require the presence of an observer at a great height in the atmosphere. Mr Welsh, of the Kew Observatory, was the observer, and Mr Green s great Nassau balloon was employed, Mr Green himself being the aeronaut. Four ascents were made in 1852, viz., on August 17, August 26, October 31, and November 10, when the respective heights of 19,510, 19,100, 12,640, and 22,930 feet were attained. A siphon barometer, dry and wet bulb thermometers, aspirated and free, and a Regnault s hygrometer were taken up. Some air collected at a con siderable height was found on analysis not to differ appre ciably in its composition from air collected near the ground. The original observations are printed in extenso in the Philo sophical Transactions for 1853, pp. 311-346. The lowest temperatures met with in the four ascents were respectively 8-7 FaJir. (19,380 feet); 12 4 Fahr. (18,370); 16 4 Fahr. (12,640); - 10 5 Fahr. (22,370); the decline of tem perature being very regular. At the meeting of the British Association for the Ad vancement of Science held at Aberdeen in 1859, a com mittee was appointed for the purpose of making observations in the higher strata of the atmosphere by means of the balloon. For the first two years nothing was effected, owing to the want both of an observer and of a suitable balloon. In 1861, at Manchester, the committee was reap- pointed, and it then consisted of Colonel Sykes (chairman), Mr Airy, Sir David Brewster, Mr Fairbairn, Admiral Fitzroy, Mr Gassiot, Mr James Glaisher, Sir J. Herschel, Dr Lee, Dr Lloyd, Dr W. A. Miller, Dr Kobinson, and Dr Tyndall. Some unsuccessful experiments were made with a balloon of Mr Green s, and also with one hired from the proprietors of Cremorne Gardens, which turned out to be in a hopelessly leaky condition; the trained observers also, on whom the committee had relied, failed to perform their duties. In this state of affairs, Mr Coxwell, an aeronaut who had made&quot; a good many ascents, was communicated with, and he agreed to construct a new balloon, of 90,000 cubic feet capacity, on the condition that the committee would undertake to use it, and pay 25 for each high ascent made especially for the committee, the latter defraying also the cost of gas, &c., so that the expense of each high ascent amounted to nearly 50. An observer being still wanted, Mr Glaisher, a member of the committee, offered himself to Mr take the observations, and accordingly the first ascent was Glaishei made on July 17, 1862, from the gas-works at Wolverhamp- ascents - ton, this town being chosen on account of its central position in the country. Altogether, Mr Glaisher made twenty-eight ascents, the last having taken place on May 26, 1866. Of these only seven were specially high ascents, although six others were undertaken for the objects of the committee alone. On the other occasions Mr Glaisher availed himself of public ascents from the Crystal Palace and other places of entertainment, merely taking his place like the other passengers. In the last six ascents another aeronaut, Mr Orton, and a smaller balloon, were employed. The dates, places of ascent, and greatest heights (in feet) attained in the twenty-eight ascents were 1862: July 17, Wolver- hampton, 26,177; July 30, Crystal Palace, 6937; August 18, Wolverhampton, 23,377; August 20, Crystal Palace, 5900; August 21, Hendon, 14,355; September 1, Crystal Palace, 4190; September 5, Wolverhampton, 37,000; September 8, Crystal Palace, 5428. 1863: March 31, Crystal Palace, 22,884; April 18, Crystal Palace, 24,163; June 26, Wolverton, 23,200; July 11, Crystal Palace, 6623; July 21, Crystal Palace, 3298; August 31, New- castle-upon-Tyne, 8033; September 29, Wolverhampton, 16,590; October 9, Crystal Palace, 7310. 1864: January 12, Woolwich, 11,897; April 6, Woolwich, 11,075; June 13, Crystal Palace, 3543; June 20, Derby, 4280; June 27, Crystal Palace, 4898; August 29, Crystal Palace, 14,581; December 1, Woolwich, 5431; December 30, Woolwich, 3735. 1865: February 27, Woolwich, 4865; October 2, Woolwich, 1949; December 2, Woolwich, 4628. 1866: May 26, Windsor, 6325. Of these, all the ascents from Wolverhampton (four in number) and from Woolwich (seven in number) were undertaken wholly for the committee, and Mr Glaisher was merely accompanied by the aeronaut, whose business it was to manage th( balloon. The expense of the special high ascents (about 50 for each, as stated above) rendered it desirable, when possible, to take advantage of the desire felt by many to accompany Mr Glaisher in his journey, and admit one or two other travellers; and of this kind were one or two of the ascents from the Crystal Palace, though the majority, in which the elevation attained frequently fell short of a mile, were the ordinary public ascents advertised before hand. It is not possible here to give any complete account of the results obtained, and it would be superfluous, as the observations, both as made and after reduction, are printed in the British Association fiejwrts, 1862-66. It will be enough, after explaining the objects of the experiments, &c., to describe briefly one or two of the most remarkable ascents, and then state the kind of conclusions that follow from them as a whole.