ISHAW-HENRYj 



SIMPLE PERIODIC CURVES 



149 



Figure 6 



Three of these variables are ordinarily independent, but this 

 number is reduced to two here, where there is a constancy in some of 

 the physical factors, and it is reasonable to associate and r' with such 

 tidal constants as vary with the time. The fact that 6 can be. kept 

 constant, while approximately the same value of A' is obtained in 

 each case, suggests further that the tidal change from day to day may 

 also be associated with the inclination of the axes of approximate 

 symmetry (measured by £) and some one other variable, determinable 

 from the graphs for consecutive tides. A series of comparisons along 

 these lines with an examination of the variation of S with the usual 

 solar and lunar constants might lead to further simplicationsjn tidal 

 analysis. 



It is considered that the perfecting of any method of analysis of 

 this general type should be taken up in some laboratory where there 

 are available, the apparatus, the methods and the experience which are 

 associated with constant work in tidal prediction and allied forms of 

 analysis. The writers have aimed to indicate the possible feasibility 

 of Dr. Dawson's suggestion, but do not feel that a complete demon- 



