VII 



FLIGHT 2 35 



higheraltitudes was to run the anemometer upthe string 

 of a kite by means of another string passed through a 

 pulley ; as soon as it had reached the right altitude a 

 third string, passed between the vanes and hanging 

 loose, was to be pulled out, thus allowing the instru- 

 ment to work. The altitude was to be measured by 

 means of a sextant. Alternate hurricanes and calms 

 put obstacles in the way of kite flying, and finally the 

 anemometer struck work and refused to register. But 

 results that arc far from valueless were obtained by 

 attaching the kite to a spring balance which measured 

 the pull at different heights. 



AUitUde ^nr ed ^ Pull of kite. 



sexta.ni. ,. 



420 feet ••• 2 5lbs. 



357 feet ^Ibs. 



350 feet... 2 4 lbs - 



204 feet l81bs - 



126 feet... 15-20 lbs. 



60 feet 14-19 lbs. 



42 feet 11— 20 lbs. 



There is the question whether the greater length of 

 string carried as the kite mounted higher may not have 

 to some extent modified the results. Probably, however, 

 the error clue to this cause was but slight. At low 

 levels, from 126 feet downwards, the jerking of the kite 

 made an accurate measurement of the pull very diffi- 

 cult. But the series suggests, though it does not prove, 

 that there is a steady though diminishing increase up 

 to 420 feet. The pull at 357 feet measured during a 

 temporary lull is the only false note in the scale. 



As a supplement to these kite-experiments, I tried 

 the plan of letting go a number of small balloons, 



