29 

 The ratio ^ is a function of ^ and -=r>and consequently, the energy 



may be expressed as 



E- 



wLhV 



(i-m|-:) 



(37) 



d 



The quantity M is shown in figure 12 as a function of j. It is evi- 

 dent that equation 33 is the limiting case of equation 37 as y in- 

 creases, and that the two equations are identical for y-=0.5. 



REDUCED TROCHOID 



Figure 11. 

 The power transmitted per unit of crest width is 



For both deep-water and shallow-water waves, Gaillard (16) states 

 that the potential energy is transmitted ahead with the wave form. 

 The equations for the power transmitted are based on this relation- 

 ship. 



Section 5. WAVE GROUPS AND TRANSMISSION OF ENERGY 



It is frequently observed that waves break on the shore in "sets," 

 reaching a maximum at regular intervals as, for example, at every 

 seventh wave. There appears to be nothing unique about a beat 

 frequency of seven except that when the number in the group is less, 

 the variation in height is small, and when more waves are mvolved 

 the interval covered by the passage of the group is too long to be noted 

 by the casual observer. In wave tanks, wave groups may be generated 

 by operating the wave machine through only a few strokes. In both 



