Ogtlvte 
DISCUSSION 
Ernest O. Tuck 
Untverstty of Adelatde 
Adelatde, Australta 
I have just one very small comment. The nature of the two- 
dimensional problem that Professor Ogilvie is solving is, in fact, that 
of a Cauchy-Poisson problem. The co-ordinate x appears as a para- 
metric co-ordinate, since it does not enter the governing field equation, 
so that it plays a role which is identical to the role played by time in 
a two-dimensional Cauchy-Poisson problem. In fact, with that inter- 
pretation the problem solved by Professor Ogilvie here actually cor- 
responds to a growing wedge in a Cauchy-Poisson two-dimensional 
problem and presumably the Baba problem is the equivalent of a pres- 
sure distribution on a free surface which is growing laterally as well 
as increasing with time. 
REPLY TO DISCUSSION 
T. Francis Ogilvie 
Untverstty of Mtchtgan 
Ann Arbor, Michtgan, U.S.A. 
I should have recognized that. Of course, Wagner recognized 
that many years ago when he put these two problems together in one 
paper. 
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