113 The Kev. S. Haughton on the Solar and Lunar 



Adding together the first two of each of the preceding series 

 of valuesj we tiud — 



Range of lunar tide at high water =0"76 ft. 

 Range of lunar tide at low water =0-33 ft. 



Hence by equation (3), 



cot (m-i^) = -^ = cot (23° 28') ; 



which, converted into time^ gives 



but m, the moon's hour-angle at high water, is, in Rathmullan 

 time, 5*^ 43*", and therefore 



i„. = 4h 6°^. 



By equation (4), we have 



max. value of 2M sin 2fi= \/ (076)2+ (0-33)2=0-829 ft. ; 



from which we obtain 



M= 0-632 ft. 



And since the maximum value of the solar tide is 0*23 feet, we 

 have, by equation (5), 



max. value of 2S sin 2(7 =0-46 ft., 

 and therefore 



S =0-315 ft. 



Combining together the preceding results, we obtain the fol- 

 lowing diurnal tidal constants for Rathmullan : — 



1. Lunitidal interval =4'* Q^. 

 3. Solitidal inten-al =9i» 40«». 



3. Age of lunar tide 



at high water =5'' IQi^. 

 at low water =4d 2Qi^. 



4. Lunar coefficient =0-632 ft. 



5. Solar coefficient =0-315 ft. 



6. Ratio of solar to lunar coefficient, 



or I =0-498. 



The solar and lunar tides were carefully constructed from the 

 preceding constants, and compared with the observed tides. The 

 results of this comparison are given in the following six Tables. 



