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LVI. On some Effects of Vibratory Motion in Fluids ; on the 

 Attraction due to the Flow of Liquids from an Expanded Ori- 

 fice ; and Laboratory Notes. By It. H. Ridout*. 



On some Effects of Vibratory Motion in Fluids. 



ON causing a stream of coal-gas to bubble through a liquid 

 contained in a flask, it may by careful adjustment be 

 made to issue from a suitable jet in an oscillatory manner, in 

 the plane which would contain a sensitive flame issuing from 

 the same jet. Thus a flame may be sensitive when the dis- 

 turbance is imparted from within. 



An analogous experiment with water was attempted as fol- 

 lows: — An electromagnetic engine was made to oscillate a 

 lever, pressing against an india-rubber tube, conveying water 

 from a height of 14 feet to a partially closed tube, such as 

 would emit a sensitive flame under a moderate pressure. The 

 water issued in a pulsatory manner, but showed no new form. 



On comparing the two experiments, it will be seen that the 

 bubble of gas, in passing through the liquid, is gradually in- 

 creasing in volume, and when it reaches the surface, probably 

 expands to a size it could not permanently retain. Such is 

 not possible with water ; for though its elasticity is greater 

 than that of air, the range through which it acts (which may 

 be called its amplitution) is much less. To provide for this 

 amplitution, an air-chamber was introduced between the lever 

 and the jet (fig. 1). The water then issued in exactly the 



Fig. 1 (section). 



,G> 



K\\\\\\\\\\\\\\\\\\\\\\\\\\\\\^ 



I R 



L = Lever. 

 I E/ = India-rubber tube. 

 A = Air-chamber. 

 B = Air-bubble. 

 J = Jet. 



same manner as an excited sensitive flame, breaking into two 

 streams lying in one plane. The motion of the lever upon the 

 flowing water produces in the latter a sinuous wave ; and as 

 the troughs and crests reach opposite sides of the jet, they 



* Read before the Physical Society. 



