Propagation of Disturbance in a Dispersive Medium. 167 

 Fig-. 4. 



1 \*' 



\ i 

 i » 



// 



Fiar. 5. 



Fig. 5 is obtained by plotting the positions of the particles 

 at the instants f/r = 0, 2, 6, 11; we can trace the progress of 

 the disturbance outwards from the central particle. Fig. 5 



