312] REFERENCE-. 579 



into account*. He concludes that the linear flow of a fluid through 

 a pipe, or of a stream over a plane bed, is stable for infinitely 

 small disturbances, but that for disturbances of more than a certain 

 amplitude the motion becomes unstable, the limits of stability 

 being narrower the smaller the viscosity. A portion of the 

 investigation has been criticised by Lord Rayleighf; and there 

 can be no question that the whole matter calls for further 

 elucidation^. 



* "Rectilinear Motion of Viscous Fluid between two Parallel Planes," Phil. 

 Mag., Aug. 1887 ; " Broad River flowing down an Inclined Plane Bed," Phil. Mag. , 

 Sept. 1887. 



t I. c. ante p. 574. 



J The most recent contribution to the subject is a paper by Reynolds, " On the 

 Dynamical Theory of Incompressible Viscous Fluids and the Determination of 

 the Criterion," the full text of which has not yet been published. Proc. Roy. Soc., 

 May 24, 1894. 



372 



