study of Reforming of Waves After Breaking; Tests of reforming 

 waves, and the relation between the energy of the reformed wave and 

 the initial unbroken wave have been made for a smooth iSlope, and for 

 two bar shapes (for numerous depths and wave conditions) and the data 

 is now being analysed. Preliminary analysis indicates that the 

 increase in water level at the shore due to mass transport has an 

 inportant effect. 



Groin Study; A new project is being initiated to study the effect 

 of groins on beaches, and the rate of littoral drift passing a groin 

 field. The test is presently being set vcp in the Coast Model Test 

 Basin where waves will be generated at a 30-degree angle to a sand 

 beach containing a groin field; material will be fed into the littoral 

 regime at the i^jbeach end (at varying ratios of the equilibrium rate) 

 and measurements of the material passing the field will be made at the 

 dowiibeach end. 



Routine progress, testing and analysis has been made on the other 

 projects being carried out by the Research Division, In addition, a 

 three-week class on water wave phenomena and design was held for 

 representatives of some of the coastal Districts, Division, and other 

 offices of the Corps of Engineers; several representatives of the 

 Department of Public Works of Canada also attended. A report on 

 "Coast Erosion and the Development of Beach Profiles" by the Danish 

 engineer Per Bruun discussing methods of analysis of shore problems 

 used abroad, and the application of some of these to profiles in the 

 Mission B^, California area, was conpleted and is being published as 

 Technical Memorandum hh* 



22. 



