ON THREE BALLOON ASCENTS IN 1865 AND 1866. 



395 



Table YII. {continued.) 

 T'vvENTT-SEVENTH AscENT (continued). 



The temperature of the dew-point on the ground and to the height of 

 1800 feet was very little below that of the air, and consequently the air 

 was nearly saturated with moisture, and was quite so at 1900 feet high ; after 

 this the temperature of the dew-point was again a httle below that of the 

 air, tUl 2600 feet was reached, when the aii- Avas again saturated ; at heights 

 exceeding this the two temperatures separated more and more, tiU at 3800 

 feet high the air was the driest, the degree of humidity being 68 only. At 

 heights exceeding 3900 feet the air became somewhat more damp to 4200 

 feet high, and then again somewhat less so at 4600 feet. 



