Be a 
PRESENT STATE OF OUR KNOWLEDGE OF THE UPPER ATMOSPHERE. 75 
which observations had been made,' and later (in 1901) Berson and Siiring 
rose to 10,800 m.? On the latter occasion both aeronauts were uncon- 
scious at the maximum height, and revived only after the balloon had 
descended about 4,000m. In Glaisher’s famous ascent from Wolver- 
hampton, September 5, 1862, the last observation was made at 8,900 m., 
although the balloon was supposed subsequently to have risen 2,000 m. 
higher.’ Special precautions were taken to make the two series of ascents 
comparable, Berson going so far as to make an ascent from the Crystal 
Palace in September 1898, a simultaneous ascent being made from Berlin. 
The final results showed that Glaisher’s results for temperature were 
faulty, the error probably arising through insufficient ventilation. In 
the ascent of December 1894 the temperature at the maximum height 
was —54° C. by the aspirated thermometer and —11° C. by the exposed 
thermometer. The results, together with those of Berson and Siiring, 
and of a simultaneous ballon-sonde ascent, are shown for comparison in 
the table 4 :— 
Fall of Temperature ° C. per 1,000 metres 
: July 31, 1901 
Height, metres Glaisher Berson Bevan ’ Ballon- 
& Siirmg sonde 
0-1,060 T5 5:0 72 8:3 
1,000-2,000 6°5 5:0 ected Lhe Gal 
2,000-3,000 5:0 5-4 lat Gah 8 tage 77 
3,000-4,000 4-2 5:3 eee Chen 61 
4,000-5,000 38 64 | TA 57 
5,000-6,000 3:2 6:9 | | 5b 63 
6,000_-7,000 3:0 6°6 aint ce? 4:7 
7,000-8,000 2:0 70 eae, 76 
8,060-9,000 1:8 9:0 | 3°6 (ell 
It will be noted that in Berson’s observations there was no indication 
of the isothermal zone discovered by Teisserenc de Bort and Assmann.” 
Later experiments with free manned balloons have been in most 
cases confined to lower altitudes and have been made principally for 
comparison with, and verification of, observations made by other means. 
Captive Balloons—Atter Glaisher’s work in 1869, captive balloons 
were little used for scientific purposes until 1890. In 1876 Mendeléef 
proposed to construct a large captive balloon and to fit it with apparatus 
of his own design,’ and in September 1889 tests of barometer-height 
formule were made by means of a captive balloon in Russia; but in 
‘general the shocks and jars sustained by these balloons owing to gusts 
of wind, together with their violent oscillations and frequent rapid rotation, 
rendered them extremely unsuitable for mercury barometers, while in 
winds of only moderate strength they refused to rise to any considerable 
height and drifted along close to the ground. E. D. Archibald in 1885 
proposed to employ a captive kite-balloon to get rid of the captive balloon’s 
defects, and in 1887 claimed to have obtained satisfactory results.’ The 
1 Nature, vol, liii. p. 136. 
2 Ergebnisse der Arbeiten am Aéron. Obs. Berlin, 1900-1901, pp. 224-233. 
* § Brit. Assoc. Reports, 1863; Travels in the Air, Glaisher. 
* Nature, vol. lxv. p. 224. 
5 The ballon-sonde record indicated that it was reached at 12 km. 
§ Nature, vol. xiv. p. 517. 7 Tbid., vol. xxxvi. p. 278. 
