( fill ) 



cenioits would however lie iinieh smaller tliaii halt' the lireadlh of 

 the band. Tliis is easilv seen, if we divide the value of»,",, — //„ 

 cak'ulated from (43) In die value of )i — //„ that is given hy (29). 

 The result 



1 



2 r «„ T 

 is (cf. §12) a small fraction, because n^x is equal to the number of 

 vibrations during the time t, multiplied by 2 -t. 



(January 25, 1906). 



