250-251] 



WAVE-PATTERN. 



457 



on the down-stream side then approximates to the form investigated in Art. 

 228, except that the curve, after approaching the axis of x near the origin, 

 runs back along the asymptotes. On the up-stream side we have approxi 

 mately 



j = &sec 2 # (i), 



where b = \a cos 4 a. This gives 



251. Another problem of great interest is the determination 

 of the nature of the equilibrium of a cylindrical column of liquid, 

 of circular section. This contains the theory of the well-known 

 experiments of Bidone, Savart, and others, on the behaviour of a 

 jet issuing under pressure from a small orifice in the wall of a 

 containing vessel. It is obvious that the uniform velocity in the 



