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DISCUSSION 



L, van Wijngaarden 



Twente Institute of Technology 

 Ensahede 3 The Netherlands 



I would like to ask a question about the authors' Interpretation 

 of Taylor's Instability, Th,/ use as a criterion for marginal sta- 

 bility that the normal component of the pressure gradient at the 

 Interface between gas and fluid vanishes. This Is Indeed the case 

 for a plane Interface, 



622 



