ON THE COASTS OF IRELAND. 



103 



The comparison of these numbers with the irregularities in the heights of the water 

 amply supports the law of Daussy, Whewell, and Bunt, that a negative irregularity 

 in the height of the barometer is accompanied by a positive irregularity in the height 

 of the sea, twelve or fourteen times as great as that of the barometer. 



Section XII.-- — Discussion of range of tide, or coefficient of Jirst arc in the analysis 

 of individual tides ; and of semimenstrual inequality in range, apparent proportion 

 of solar and lunar effects, and age of tide as deduced from range. 



The tides were divided into groups of large tides and small tides, separated at the 

 same times as those particularized in pages 29 and 96. For each of these groups the 

 mean of the values of C^ was taken, some deficient values being supplied by interpo- 

 lation. The moon's parallax and the square of the cosine of the moon's and sun's 

 declinations were taken for two days preceding each tide, and the means of these 

 quantities were taken through the same groups. 



A general result will be obtained by forming the sum of the mean values of C^ for 

 all the stations in each group. Thus we obtain : — 



