SCIENTIFIC BALLOON ASCENSIONS VON BEZOLD 



3°5 



pie, on the dates and the times when the balloon ascensions Nos. 16, 

 17, 30, 37, and 51 were made 6 the very pronounced inversions would 

 have been entirely overlooked if one had at hand observations at 

 only one station in the lower plain and one at an altitude of 1000 

 meters. 



Again, the full extent of the inversion within comparatively 

 small elevations can only be observed by means of balloons. For 

 example, during balloon voyage No. 22, on January 12, 1894, the 

 following temperatures were observed ; at the ground — 6° C. ; at 

 400 meters, + 6.5 C; giving a temperature gradient of + 3.2 : but 

 on February 24, 1891 (ascension "G," fig. 41) there had been 

 observed at 230 meters — 2 , whereas at 340 meters this had risen to 

 + 9 , corresponding to a gradient of + 10. o° C. per 100 meters. By 

 experiment with the captive balloon "Meteor" on October 9, 1891, 

 there was observed at about 5 h. 27 m. p.m. an increase of tem- 

 perature of 2 between 1.5 meters and 8 meters above the ground 

 corresponding to a gradient of 25. o° C. 



A very interesting diagram is formed by extending downward 

 the main branch of various curves of this type, as is done in fig. 41, 

 for the curves of the voyages "G," Nos. 22, 54, and 55, and then placing 

 near them the curves for cases that correspond to the heating of the 

 soil such as are typically represented in voyages Nos. 72 and 6gb — 70. 



The numerals for the voyages are entered near the respective 

 lines; the curve marked "G" refers to an ascension made by Captain 

 Gross on February 24, 1891, and which does not belong to the general 

 series. The sides of the small squares correspond to 200 meters 

 altitude and 2 difference of temperature. The whole number of 

 degrees inscribed on the bottom line indicate the scale numbers 

 for the observed temperatures on the respective curves. From 

 this diagram we see at a glance how differently the warming and 

 cooling of the earth's surface affects the air and we comprehend how 

 seriously the cooling influence must affect the average values. 



Explanation of fig. 4.1 



Day I Month Year 



DURATION UP TO MAXIMUM 

 ALTITUDE 



Reference 



Wissenschaftliche 



Luftfahrten. 



G 



22 



54 



55 



69b 



70 



72 



II 

 I 

 II 

 II 

 VI 

 VI 

 IX 



[891 1 i vol. l| p/io5-io6 



1894 

 1897 

 1897 



189S 



9:i5a.m. to 1:06p.m. 

 |io:ioa.m. to 4:18p.m. 



9:40a.m. to 2:iSp.m. 

 Descent 1 to 3:08 p.m. 

 ii:55a.m. to 6:i5p.m. 



2:o5 p.m. to 3:05 p.m. 



:} 



11 j 225-236 



II] 5oo-5i6 



II 566-588 



II' 594-604 



6 See the Wiss. Luftfahrten, Vol. II, pp. 167, 176, 305, 371, 457, respectively. 



