174 



REPORT — 1859. 



It has already been remarked, that the difference between the observed 

 and calculated dip for a station is more likely to be due to local attraction 

 than to error of observation. Local attraction, again, may be presumed to 

 depend on the geological formation of the neighbourhood. In the following 

 Table the difference between the observed and calculated dips is compared 

 with the geological character of the station. 



In this Table, the latitudes and longitudes, unless when the contrary is 

 specified, are obtained from a Map of Scotland published by the Society for 

 the Diffusion of Useful Knowledge, while the geological character of the 

 station is obtained from Prof. Phillips' Geological Map of Great Britain and 

 Ireland. 



Table VI. 



t Determined by astronomical observations. 



% Obtained through the kindness of Colonel James. 



