180 



EIGHTH REPORT — 1 838. 



Substituting these values in the formulae of page 1.34 (Fifth Re- 

 port), we find 



S.^■ = + -0003, Sy = - -0012 ; 



.v = a + Sx = 1'0197; 

 1/ = h + Sy = 1-0250. 

 The results in the 6th column of the following table are deduced 

 from those of the 5th, by multiplying by one or other of these 

 numbers, according as the station has been originally compared 

 with Dublin or with Limerick. 



The iveights due to the preceding determinations are given 

 by the formulae of page 170. Substituting the numerical values 

 of A, B, C, &c., we find 



X = 5-7, Y = 2-4 ; 

 the weight of a single comparison being unity. Adopting the near - 

 est whole numbers, we may consider the deduced value of the in - 

 tensity inDublin as equivalent to the result of *<> separate compa- 

 risons j and that of the intensity in Limerick as equivalent to two. 



Table LXXV. 

 Intensity of the Total Force. 



* Evident local distuvbance at these two stations. The district about Cav- 

 lingfovd is intersected \Yitli trap djkcs ; Colevain lies within the basaltic field 

 of the North East gf Ireland. 



