156 



eighth report — 1838. 

 Table LV. 



Whence it results that ( — - — "^ ) = 1*0261 expresses 



the force at Helensburgh relatively to unity in London, as de- 

 rived through the medium of Dublin. 



In 1838 I visited Helensburgh for the purpose of obtaining a 

 direct comparison with London. The observations vifhich I then 

 made are included with the series already given in Table XLV; 

 their result is 1 '0252. The near agreement of this result, with 

 that obtained in 1836 through the medium of Dublin, is satis- 

 factory, both in confirming the relation of the Scottish inten.^i- 

 ties to London, and in showing the confidence to which this 

 mode of experiment is entitled. I have taken 1*0258 as the 

 force at Helensburgh, considering the determination through 

 Dublin as entitled to rather the most weight ; and have com- 

 puted from it the value of the intensity at the other stations, 

 as inserted in the final column of Table LVL 



