250 Temperature of the Atmosphere made by Balloons. 



Hour?. 

 P. M. 

 B. M. 



Thermo- 

 meter 

 below. 



6 



We begin to haul in the line. Bright sun- 

 shine, and strong breeze, - - 59 



We descended 150 feet to leeward, to 

 escape the wind, which strained the line 

 so much, we feared it might break. 

 6 20 Here we got the balloon down. Still 



bright sunshine, - - 60 



We proceeded homewards, and on getting 

 round under the shadow of the hill, I 

 ,, found the thermometer at, - 6Q 



7'- 1(5 Sent the balloon up in front of the house, 53 

 „j It floated immediately over our heads at 



'"-'' the full extent of the line, 1340 feet. 



Although the sun was set to us there 

 was sufficient light in the north-west to 

 enable us to see it in the form of a cres- 

 cent on one side of the balloon. 

 7 40 No light on the balloon. We began to 



lower, . _ . 5%B 



7 47 The balloon down, - - 52 



I then sent the balloon up 100 feet, and 



after some time found the thermometer 52 

 The same experiments repeated gave the 

 same result at 100 feet, for the register 

 thermometer ; it had become too dark to 

 read off the lower thermometer apcurately, 



Six's 

 Thermo- 

 meter at- 

 tached to 

 Balloon. 



54 



51.25 



5±S 



52.5 



On this day the barometer stood unusually high, viz. at 

 30.1. The hygrometer indicated an atmosphere much charged 

 with vapour in the forenoon, — in the afternoon it became ob- 

 viously much dryer. . 



The register thermometer (Six's) attached to the balloon, 

 hung freely in a cylindrical case of glazed pasteboard, open at 

 each end. The thermometer below was suspended in a simi- 

 lar case of writing paper ; and in the second experiment on the 



3 •^' . ■ 



