220 Screntifie Intelligence. 
Gas is introduced into this box by one tube and then conducted 
fro b burn ‘ i i 
vi 
in the pipe plays upon the membrane, and communicates vibration 
to the flame. The individual vibrations of the flame are revealed 
self a faint and virtual image, not easily seen in daylight or in all 
directions. It has the advantage of admitting of a large orbit of 
revolution and thus separating widely the individual vibrations of 
ven high note 
; one foot in length, arranged as the spokes of a horizo 
tal wheel upon a hollow hub, which is lengthened out below to the 
extent of six inches, is closed at the upper end by st 
V 
lighted, the rotation produces a large cylindrical sheet of light. 
umber of arms t is the velocity Te 
ed to produce persistency of impression in the eye, ets 
. ibra- 
